Keylight ae user guide

USER GUIDE
Tinder Box1 The Foundry
Keylight on After Effects
Visual Effects Software The Foundry

The Foundry Tinder Box1
©2007 The Foundry Visionmongers Ltd. All rights reserved.
Keylight User Guide
This manual, as well as the software described in it, is furnished under license and may only be used or copied in
accordance with the terms of such license. This manual is provided for informational use only and is subject to change
without notice. The Foundry assumes no responsibility or liability for any errors of inaccuracies that may appear in this
book.
No part of this manual may be reproduced, stored in a retrieval system, or transmitted in any form without the prior
written permission of The Foundry.
The Foundry logo is a trademark of The Foundry Visionmongers Ltd. After Effects is a registered trademark of Adobe
Systems Incorporated. All other products or brands are trademarks or registered trademarks of their respective
companies or organisations.
Software engineering Ralph McEntagart, Lucy Hallpike, Andy Whitmore, Bruno Nicoletti, Simon Robinson.
Initial algorithm development Wolfgang Lempp and Oliver James.
Product testing Rob Elphick, Jack Binks, Jonathan Barson.
Writing and layout design Jonathan Barson using Adobe FrameMaker.
Proof reading Jonathan Barson.

iii
Keylight The Foundry
CONTENTS
Introduction About this Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Release Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Example Images . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Installation on Mac OS X . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Installation on Windows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Licensing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
About The Foundry. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
About CFC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Getting Started Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Quick Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Basic Keying Basic Workflow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Screen Colour. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
View . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Status. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Despill Bias. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Advanced Keying Screen Colour. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Despilling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Screen Gain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Screen Balance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Clip Levels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
View . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Status View . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Screen Matte . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Clip Rollback. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Grow & Shrink . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Despot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

iv
The Foundry Keylight
Colour Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Inside & Outside Masks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Source Alpha . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Colour Correction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Edge Colour Correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Source Crops . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Tutorial Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Example Images . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Tutorial 1: Simple Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Tutorial 2: Fine Tuning a Key. . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
Tutorial 3: Extreme Blue Spill . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
Tutorial 4: A Red Green Screen . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Tutorial 5: Inside & Outside Masks . . . . . . . . . . . . . . . . . . . . . . . 65
Appendix A Release Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Appendix B End User License Agreement . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
Index A-Z. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

About this Manual
INTRODUCTION 5
INTRODUCTION
Welcome to this User Guide for Keylight on After Effects.
Keylight is an Academy award winning blue and green screen
keyer. The core algorithm was developed by the Computer
Film Company and has been further developed and ported to
After Effects by The Foundry.
We hope you enjoy using Keylight.
About this Manual Use the Quick Key chapter to see how a simple key is pulled
using Keylight. The Basic Keying Chapter goes over the most
common parameters you’ll need to pull a variety of keys. The
Advanced Keying Chapter explains how to tackle difficult
keys.
Release Notes For information on system requirements, new features,
improvements, fixed bugs and known bugs & workarounds,
see “Appendix A” on page 71.
Example Images Example blue and green screen images for use with Keylight
can be downloaded from our web site www.thefoundry.co.uk
Installation on Mac
OS X
To install Keylight on a Mac OS X machine follow these
instructions:

INTRODUCTION
6
Installation on Windows
1. Download Keylight1.2v8_AECS3-mac-universal-release-32-
Pro.dmg from www.thefoundry.co.uk and extract the package
by double clicking on it.
2. Double click on Keylight1.2v8_AECS3-mac-universal-release-
32-Pro.pkg
3. Follw the on screen instructions to install keylight
4. Quit
5. That’s it!
Keylight can be found in the Effect - Keying menu.
Installation on
Windows
To install Keylight on a Windows machine follow these
instructions:
1. Download and run Keylight1.2v8_AE7.0-win-x86-release-32-
Pro.exe from www.thefoundry.co.uk.
2. A window will appear welcoming you to the Keylight Setup. Click
Next to continue to the end user license agreement.
3. When the end user license agreement appears, please read it. If
you agree, click Yes to continue the installation.
4. Choose the location to install Keylight on your hard disk. To
accept the default location, and it is strongly recommended
that you do, just click Next to continue.
5. The Keylight plug-in will be installed but not licensed.
6. Click Finish to quit the installer.
7. That’s it!
Keylight can be found in the Effect - Keying menu.
Licensing Versions of Keylight for After Effects Standard are licensed
using FLEXlm from Macrovision. The version of Keylight that

Licensing
INTRODUCTION 7
ships with After Effects Professional (AE7 and AECS3) does
not require a license key, but will only run on the
Professional version.
A node locked license will enable Keylight to work on one
particular machine. It is locked to a unique number (lmhostid)
on that machine. Node locked licenses do not require
additional licensing software to be installed. In particular
you do not need a FLEXlm daemon running. You just need the
Keylight plug-in and a text file containing the license string.
Your license key will look a little like this:
INCREMENT keylight_ae_i foundry 1.2 05-jul-2007 uncounted
HOSTID=000ea641d7a1 START=8-nov-2006 SIGN="03C7 5A34
BDE8 D421 6C2B 8111 8151 972A 14E2 C143 4C00 741F 730D
784A D392 B1D9 9C3F 03FC DB2A E432 5EA7"
This license string should be put in a text file called
foundry.lic in the same directory as the Keylight plug-in.
Important! The really important bit is that the file has a .lic file extension
(make sure there is no hidden file extension has been added for
you), that it is a plain text file (not rich text) and that you put the
file in the correct directory.
For Windows here is the license key:
C:Program FilesAdobeAdobe After Effects CS3Support
FilesPluginsKeylight-1.2foundry.lic
For Mac OS X here is the license key:
/Applications/Adobe After Effects CS3/Plug-ins/Keylight-
1.2/foundry.lic
You can get a temporary trial (demo) or permanent license
from our web site www.thefoundry.co.uk or contact The
Foundry directly.

INTRODUCTION
8
About The Foundry
lmhostid To display this number click the About button in the Keylight
plug-in. The lmhostid is displayed.
Further Reading For more information on licensing Keylight, moving the
license file or working with floating licenses, read the
Foundry FLEXlm Tools (FFT) User Guide available to
download from our web site.
About The Foundry The Foundry specialises in developing plug-in visual effects
for compositing platforms in the film and video industry.
Based in London's Soho, the Foundry has tailored its image
processing tools to the needs of post production.
Nuke is an Academy award winning compositor from The
Foundry.
Tinder plug-ins have been developed by the Foundry and
have been sold to hundreds of users throughout the world.
They are available on the leading compositing platforms
including Discreet Frame, Avid DS, Shake and Adobe After
Effects.
Furnace is a rich collection of image processing tools using
motion estimation technology to help compositors tackle
common problems when working on films. Plug-ins include
wire removal, retiming, rig removal, texture plug-ins, grain
management, steadiness and deflicker.
Anvil is a set of colour correction and colour manipulation
tools. It was originally developed by Paul Grace at First Art
and is now available on a variety of platforms.

About CFC
INTRODUCTION 9
Visit The Foundry’s web site at www.thefoundry.co.uk for
further details.
About CFC The Computer Film Company (CFC) pioneered the field of
digital film compositing and today operates a state of the
art film effects facility in London. The company has always
invested in research, and maintains the kind of edge that has
twice been honoured with Technical Achievement Awards
from the Academy of Motion Picture Arts and Sciences.
Visit Framestore-CFC’s web site at www.framestore-cfc.com
for further details.

INTRODUCTION
10
About CFC

Introduction
GETTING STARTED 11
GETTING STARTED
Introduction Keylight has been refined over a number of years to make
keying quicker and easier while providing a depth to the
tools that will tackle even the most challenging shots.
Keylight was first developed by The Computer Film Company
to help with difficult keys in feature films. Over the years
Keylight has been refined in production on hundreds of films.
This pioneering work on digital compositing was honoured
with a Technical Academy Award® in 1996.
Notation When we refer to blue screens throughout the text we mean,
of course, blue or green screens.
Quick Key Keylight is available from the Effect - Keying menu in After
Effects.
Consider this shot from The Saint, pictures courtesy of CFC
and Paramount British Pictures Ltd. Figure 1 is the blue
Figure 1. Blue Screen.

GETTING STARTED
12
Quick Key
screen foreground that should be composited over the
background shown in Figure 2.
If you want to have a go of this shot, you can! The images
can be downloaded from our web site and this quick key is
also covered in the Tutorial Chapter. See “Tutorial 1: Simple
Key” on page 49.
Throughout this user guide we assume a good understanding
of After Effects. To perform this quick key, do the following:
Figure 2. Background.

Quick Key
GETTING STARTED 13
1. Create a new composition using SaintFG.tif and SaintBG.tif.
Layer the clips with the blue screen over the background as
shown in Figure 3.
2. Select the blue screen clip (SaintFG.tif) in the Time Layout
window and apply Keylight from the Keying sub-menu of the
Effect menu. See Figure 4.
Figure 3. Screen Shot showing Saint blue screen.
Figure 4. Apply Keylight from the Effect - Keying menu.

GETTING STARTED
14
Quick Key
3. The Keylight parameters are shown in Figure 5.
4. Select the Screen Colour eye dropper and click on the blue
screen in the composition window. A good place to pick is the
blue from the back windscreen as this has no reflections.
Picking this blue will key the back windscreen perfectly leaving
reflections in the side window.
5. That’s it. In many cases this is all you will need to do to perform
a key, since selecting the screen colour creates a matte and
Figure 5. Keylight Parameters.
Figure 6. Pick the blue from the back windscreen.

Quick Key
GETTING STARTED 15
despills the foreground. The final composite is shown in
Figure 7.
There are a couple of extra steps that can be taken to fine
tune this key and these are discussed in “Tutorial 2: Fine
Tuning a Key” on page 54.
Picking the screen colour may be enough for a lot of keys,
but there are many more tools within Keylight that can be
used to tackle more complicated shots. These are described
in later chapters.
Figure 7. Final composite.

GETTING STARTED
16
Quick Key

Basic Workflow
BASIC KEYING 17
BASIC KEYING
The following section describes the parameters you need to
do basic keying. This will give you enough to tackle most
simple keys. A discussion of advanced parameters to fine
tune and tackle complex keys can be found in the next
chapter.
Basic Workflow The first step is always to pick the Screen Colour. Then view
the composite and the screen matte.
If there is blue spill on the composite pick skin tones for the
Despill Bias from the foreground actor.
If the background is showing through the foreground or the
foreground is showing on the background, you need to
improve your matte using the Clip Black and Clip White
parameters. In the next chapter we’ll look at ways of doing
this with inside and outside masks. See “Inside Mask Tip” on
page 42.
Screen Colour The Screen Colour is probably the most important parameter
and you should always pick the screen colour before doing
anything else. It should be set to the colour of the green or
blue curtain behind the foreground object. View the Source
image in the Composite window, select the eye dropper and
pick the screen colour. Setting the Screen Colour will create
a matte - the Screen Matte - and despill the foreground. In
some cases this is enough to get a decent key. For more
information on Screen Colour see page 23.

BASIC KEYING
18
View
Figure 8 shows a well lit blue screen behind an actor. You
should note that repeatedly picking the Screen Colour will
override any previous selections. It will not add to previous
selections and key more of the image with each click.
Note You should always pick screen colours from the Source image and
not the Final Result.
Tip
It’s worth picking several different blues and for each one
viewing the matte and status to judge the key.
View After picking the Screen Colour it’s useful to be able to check
the quality of the key by viewing the composite and the
Figure 8. Blue Screen.

Status
BASIC KEYING 19
screen matte. You can do this using the View Menu, shown
here in Figure 9. The options you’ll use the most are:
• Screen Matte - this renders the matte created by picking
the screen colour.
• Status - this renders an exaggeratted view of the mattes
so that minor problems are shown clearly.
• Final Result - this renders the foreground composited
over the background using all mattes, spill and colour
corrections.
Status The Status is one of the options in the View menu and shows
an exaggerated view of the key so that you can make a more
informed decision when refining the composite. Figure 11
Figure 9. View Menu.
Figure 10. Green Screen. Figure 11. Status.

BASIC KEYING
20
Despill Bias
shows the Status display after the screen colour has been
picked from the image shown in Figure 10. Three colours are
displayed. Black pixels show areas that will be pure
background in the final composite. White pixels show areas
that will be pure foreground. Mid-grey pixels will be a blend
of foreground and background pixels in the final composite.
You need grey pixels around the edge of the foreground to
get a good key at the foreground edge. However, if there are
grey pixels where there should be pure background, you
should try to remove these with the Screen Strength, Clip
Black or Outside Mask. If you have grey pixels where there
should be pure foreground this tells you that parts of the
background will show through here and you will need to firm
up the foreground with Clip White or an Inside Mask.
Pixels that are a blend between the foreground and
background are shown in just one shade of grey. This is done
to highlight potential problems with the key. These grey
pixels may represent a foreground/background blend of 50/
50 or 99/1. No distinction is made as to this ratio.
You may occasionally see other colours in the Status View
and these are covered on page 34 in the Advanced Keying
Chapter.
Despill Bias Although the foreground is despilled automatically, you may
find the need to pull out a little more of the screen colour

Despill Bias
BASIC KEYING 21
after picking from the image. You can do this with the Bias
controls.
By default the Bias controls are locked together, which in the
vast majority of cases, is the best way to use them. See
“Despilling” on page 26 in the Advanced keying section for a
look at a case where unlinking the bias controls is a good
tactic.
Thus, using either bias control colour dropper, pick the
predominant foreground colour. In the majority of cases it’s
best to pick skin tones from the foreground actor, as viewers
tend to be most tuned to colour shifts in these areas.
Figure 12. Exaggeratted blue
spill.
Figure 13. Despill Bias used to
remove the blue spill.

BASIC KEYING
22
Despill Bias

Screen Colour
ADVANCED KEYING 23
ADVANCED KEYING
The following section describes the parameters you need to
fine tune keys and get the most out of Keylight. Basic
parameters covered in the previous chapter may also be
covered here in more detail.
Screen Colour The screen colour represents the colour of the pure blue (or
green) screen. The first thing you should do when pulling a
key is pick the Screen Colour. This single colour has a
primary component, blue or green, and that has a saturation.
Once the screen colour has been picked, Keylight analyses all
the pixels in the image and compares the saturation of the
primary component in each of these pixels with the
corresponding saturation of the screen colour, setting the
alpha and modifying the colour accordingly.
Tip
Picking different shades of blue or green from the
background can give quite different results. It’s worth
experimenting with different screen colours if your initial
pick didn’t give a good key.

ADVANCED KEYING
24
Screen Colour
Workflow Tip
It can also be useful to view the Status and Source side by
side as shown in Figure 14 so that you can repeatedly pick
from one while viewing the result in the other window.
Background Pixel
If the saturation of the pixel in the image is as strong, or
greater than the screen colour, then it’ll be a pixel from the
Figure 14. Two Views.
Figure 15. Blue screen pixel set alpha to zero.

Screen Colour
ADVANCED KEYING 25
blue screen background, and that pixel will be set to
completely transparent and black. See Figure 15.
Edge Pixel
If the saturation of the pixel is less than the screen colour,
then it’ll be the edge of the foreground object, and we
subtract some of the screen colour from the pixel (de
spilling) and set the image to semi-opaque. See Figure 16.
Foreground Pixel
If the primary component in the pixel is not the same as the
primary component of the screen colour we have a
Figure 16. Edge pixel gives partial alpha.

ADVANCED KEYING
26
Despilling
foreground pixel, and the alpha is set to completely opaque.
The pixel colour is not modified. See Figure 17.
Note You should note that the Screen Colour is a single colour. You are
not picking lots of colours that are keyed out.
Despilling Although picking the screen colour will remove blue spill, it
may not be enough. To despill more use the Despill Bias
control. By default this is linked to the Alpha Bias. In the rare
case that the screen has been so badly shot that it’s not
really blue or green anymore, the alpha bias can be used to
get a good key.
Figure 17. Foreground pixel gives full alpha.

Despilling
ADVANCED KEYING 27
Despill Bias Consider Figure 18 from the film "Merlin". Pulling a default
key from this will give the extreme blue spill around the
edges of her hair as shown in Figure 19. To reduce this
select the Despill Bias colour and pick skin tones from the
foreground image. This result is shown in Figure 20. The
alpha channel is shown in Figure 21.
Alpha Bias You should not normally need to adjust the alpha bias
seperately to the Despill Bias, but on those rare occasions
when your green screen is more red than green it can be
used to put things right in what would otherwise be an un-
Figure 18. Original blue screen. Figure 19. Default key.
Figure 20. Despill Bias. Figure 21. Alpha.

ADVANCED KEYING
28
Despilling
keyable shot. Consider the image shown in Figure 22. This
shot, from the film Executive Decision, is actually a green
screen although it doesn’t look it. The colour of the screen in
the background is around 28% red, 25% green and 8% blue.
This is in fact red, but only just. Note that the pilot in the
cockpit is predominantly brown, at around 42% red, 25%
green, 15% blue. So a default key from that screen colour
would make the foreground transparent (Figure 23) as it is a
more saturated red than the red of the screen colour.
Figure 22. Is this the worst green screen you’ve ever seen?
Figure 23. Default key showing the transparency of the
foreground.

Screen Gain
ADVANCED KEYING 29
In this situation, the Alpha Bias can help. View the Source,
unlink the Bias controls, then select the Alpha Bias and pick
colours from his mask. Now pick the same colours for the
Despill Bias. This gives the result shown in Figure 24.
Screen Gain The screen gain controls how much of the screen colour is
removed to make the screen matte. Increasing this value will
key more. For the most part, a better way of improving the
matte is using the Clip Black and Clip White controls.
Figure 25 shows the Status after picking the screen colour.
Figure 24. Alpha Bias and Despill Bias.
Figure 25. Status after picking
the Screen Colour.
Figure 26. Status showing the
increase in Screen Gain.

ADVANCED KEYING
30
Screen Balance
You can clearly see that parts of the background are grey
where they should be black. When composited you may see
faint pixels from the foreground where you should be seeing
pure background. Increasing the screen gain will fix this, as
shown in Figure 26, but increasing it too much will destroy
your good work. Like many keying parameters it’s a balance -
not too much, not too little. Increasing the screen gain too
much will lead to the background showing through the
foreground and edge detail will be destroyed. Figure 28 on
page 30 shows this quite well. Note the steering wheel is
black when it should be white. If you look at the composite
you will see the background showing through here. Also,
some of the fine hair detail on the actor, visible in Figure 27,
has been eroded in Figure 28.
Screen Balance Saturation is measured by comparing the intensity of the
primary component against a weighted average of the two
other components. This is where the Screen Balance control
comes in. A balance of 100% means that the saturation will
be measured against the smallest of the other two
components in the screen colour.
Figure 27. Screen Gain = 100
giving a good screen matte.
Figure 28. Screen Gain = 150
giving background show through
and over eroded edges.

Clip Levels
ADVANCED KEYING 31
A balance of 0% means that the saturation will be measured
against the larger of the other two components. A balance of
50% will measure the saturation from the average of the
other two components.
The appropriate balance point for each image sequence you
key will be different depending on the colours in that image.
Generally speaking, blue screens tend to work best with a
balance of around 95% and green screens with a balance of
around 50%. If the key is not working too well with these
settings, try setting the balance to about 5%, 50% and 95%
and see what works best.
Clip Levels The clip levels are adjusted using two parameters - Clip
Black and Clip White. Any alpha value at or below Clip Black
will be set to zero and any alpha value at or above Clip White
will be set to 100. Figure 29 shows the original alpha of an
image and Figure 30 on page 31 shows the result of clipping
it. Notice how the grey areas in the black background have
been reduced and that the grey edges have hardened up
considerably. When compositing, the Clip Black control can
be used to improve the background image if parts of the
Figure 29. Clip Black = 0. Figure 30. Clip Black = 50.

ADVANCED KEYING
32
View
foreground are showing through. The Clip White control on
the other hand can be used to firm up the centre of the
matte, making it less transparent to the background.
Note You need to be really careful if you chose to use Clip Black and Clip
White that you don't destroy the edges on your foreground. It is
possible to use Clip Rollback to compensate for this.
View After picking the Screen Colour it’s useful to be able to view
the key in different ways. You can do this using the View
Menu, shown here in Figure 31. Here’s the complete list of
options and what they do.
• Source - displays the blue or green screen.
• Source Alpha - displays the alpha channel embedded in
the blue or green screen.
• Corrected Source - displays the uncomposited source
image with any colour corrections applied.
Figure 31. View Menu.

Status View
ADVANCED KEYING 33
• Colour Correction Edges - displays the foreground edges
as a matte that will be colour corrected using the controls
in the Edge Colour Correction folder.
• Screen Matte - displays the matte created as a result of
picking the screen colour.
• Inside Mask - displays the mask that firms up the
foreground.
• Outside Mask - displays the mask that cleans up the
background.
• Combined Matte - displays all the screen matte, inside
and outside masks and any source alpha added together.
The combined matte is used to composite the foreground
over the background layer.
• Status - displays an exaggerated view of the key so you
can make a more informed decision on how to improve
the result. See “Status View” on page 33.
• Intermediate Result - is used for multipass keying. The
alpha is set as per normal, but the RGB values are not
modified from the original source image. See “Inside Mask
Tip” on page 42.
• Final Result - renders the foreground composited over
the image on the background track. This image is
premultiplied. In other words, the RGB values of pixels
have been multiplied by their corresponding alpha channel
values.
Status View The Status View is one of the options in the View menu and
shows an exaggerated view of the key so that you can make

ADVANCED KEYING
34
Status View
a more informed decision when fine tuning the composite.
Figure 33 shows the Status after the screen colour has been
picked from the image shown in Figure 32 on page 34. Three
colours are displayed. Black pixels represent pure
background in the final composite. White pixels are pure
foreground and grey pixels are a blend of the foreground and
background pixels. The grey is just one colour to highlight
any areas that are not pure foreground or background. Grey
pixels do not mean the key is poor - the final composite may
be fine.
You may occasionally see other colours in the Status View.
Figure 32. Green Screen. Figure 33. Status.
Figure 34. Status showing
processing of the Screen Matte.
Figure 35. Result showing Screen
Matte Replace Colour.

Status View
ADVANCED KEYING 35
Figure 34 shows black, white, grey and green pixels. The
green pixels are a warning. They show you the parts of the
Screen Matte that have changed through processing the
matte (clipped, softened or eroded). These areas have had
the correct amount of spill removed, but the alpha has
subsequently changed and the composite may no longer look
right. This can be corrected using the Replace Colour to put
back colour in these areas. Figure 35 on page 34 is an
extreme example to illustrate the point. The Replace Colour
has been set to pure red and you can see that this mirrors
the green pixels in the Status View.
Similarly you may see blue pixels in the Status. These
represent processed pixels in the Inside Mask that affect the
despill of the foreground. The Replace Colour in the Inside
Mask folder will be used to modify these pixels. Another
extreme example is shown in Figure 37. The Replace Colour
is set to pure yellow and the Replace Method is Hard Colour.
You may also see dark red pixels which indicate areas where
an outside mask has been used to reduce the transparency
of the image.
Figure 36. Status showing how
the Inside Mask will affect the
foreground.
Figure 37. Final Result showing
the Inside Mask Replace Colour.

ADVANCED KEYING
36
Screen Matte
Screen Matte The Screen Matte (Figure 39) is the result of pulling the blue
or the green from the image (Figure 38) and making those
regions transparent. Once you have done this you will want
to firm up the foreground (make it more white) and clean up
the background (make it more black). This can be done by
processing the Screen Matte.
Clip Rollback Pulling a Screen Matte (Figure 40) will typically produce lots
of transparency (grey) in the matte at the edges. This is good
since this is what you need to key hair well. You may also get
transparency in the foreground as shown in Figure 41. This
is bad as your subject will appear slightly see-through, and
Figure 38. Green screen. Figure 39. Screen Matte.

Clip Rollback
ADVANCED KEYING 37
this should be corrected. You can do this with an inside mask
shape, or you can use the Clip White parameter to turn these
grey pixels white. This cleans up the foreground (Figure 42)
but it will also destroy the edge detail you want to keep. This
is where Clip Rollback comes in. This is used to put back the
edges to restore the detail that was lost. A rather
exaggerated clip rollback is shown in Figure 43 to illustrate
the point.
Figure 40. Screen matte
highlighting the close up view as
shown in Figure 41.
Figure 41. Close up screen matte
showing unwanted (grey)
transparency in the (white)
foreground.
Figure 42. Clip White has been
used to remove the unwanted
grey pixels in the white matte.
Figure 43. Clip Rollback has been
used to reduce the unwanted
erosion of the edge.

ADVANCED KEYING
38
Grow & Shrink
Grow & Shrink This control should not normally be used as eroding the
edges can produce a very poor key. However, this parameter
allows you to grow (if greater than zero) or shrink (if less
than zero) the alpha in the Screen Matte. These controls are
sub-pixel accurate.
There is, however, one circumstance where heavy eroding is
useful and that is for producing a matte used as an inside
mask. See “Inside Mask Tip” on page 42.
Despot This controls how much to simplify the matte. It coagulates
similar regions so that, for example, black specks in the
white matte can be absorbed by the surrounding white areas.
Increasing the Screen Despot Black will remove isolated
spots of black in the white matte. Increasing Screen Despot
Figure 44. Screen Matte. Figure 45. Eroded Matte.

Colour Replacement
ADVANCED KEYING 39
White will remove isolated spots of white in the background
up to that size.
Colour
Replacement
Remember that Keylight does two things - it removes the
screen colour to despill the image and generates an alpha
(Screen Matte) to composite the foreground over the
background layer.
If you then process the Screen Matte, for example, by
eroding the matte or changing the clip levels, Keylight will be
removing the wrong amount of screen colour from the pixels
whose transparency have now changed. The Replace Method
instructs Keylight how to deal with such pixels. The Status
will display which pixels use a replace method. Those pixels
who use a replace method because the Screen Matte
processing tools modified the transparency will be green,
whilst those pixels whose transparency was modified by the
inside mask will be blue. See the Status View on page 34.
There are four options to the replace method, these are:
1. None - the despilled image is left untouched if the alpha is
modified.
Figure 46. Eroded matte. Figure 47. Despot.

ADVANCED KEYING
40
Inside & Outside Masks
2. Source - the image will have a corresponding amount of the
original pixel (screen colour and all) reintroduced/removed if
the alpha is changed.
3. Hard Colour - the despilled image has a corresponding amount
of the replace colour added for any increase in alpha.
4. Soft Colour - the despilled image has a corresponding amount
of the replace colour added for any increase in alpha, however,
it attempts to modulate the luminance of the resulting pixel so
that it matches the original pixel. This will give a more subtle
result than the Hard Colour option.
Inside & Outside
Masks
If you can’t adequately improve the Screen Matte using the
Clip Levels, you can input a mask that defines the foreground
or background. The Inside Mask makes the foreground less
transparent and the Outside Mask is used to clean up the
background that might have bits of the foreground showing
through. The outside mask is often used to clean up screens
that are not a constant colour or have lighting rigs in shot
(Figure 48) by forcing the alpha transparent. The inside mask
can be used to keep elements in the foreground that you
don't want to lose (an actor’s blue eyes in front of a blue
Figure 48. Green Screen with
lighting rig visible.

Inside & Outside Masks
ADVANCED KEYING 41
screen). These masks should normally be softened to blend
into the Screen Matte.
Figure 49 on page 41 shows an After Effects Mask drawn
around the lighting rig on the left side of the screen. When
this is used as the Outside Mask and the View control set to
render the Outside Mask, you will see the image displayed in
Figure 50. The outside mask forces that part of the image to
be in the background thus keying out the rig. The Screen
Matte shown in Figure 51 shows the matte pulled when the
green screen is picked. When the Outside Mask is subtracted
from the Screen Matte we get the Combined Matte, shown in
Figure 49. Mask drawn round the
lighting rig.
Figure 50. Mask used as an
Outside Mask and Viewed.
Figure 51. Screen Matte. Figure 52. Combined Matte.

ADVANCED KEYING
42
Source Alpha
Figure 52. Here you can see the change in the matte that will
result in the lighting rig being keyed out in the final
composite. If more than one mask is required to remove
garbage, then use the masks to create an embedded alpha
channel in the image and set the Source Alpha to Normal.
See “Source Alpha” on page 42.
Source Alpha This parameter determines how to deal with any embedded
alpha in the original image.
• Ignore - this will not use any embedded alpha in the key.
• Add to Inside Mask - the embedded alpha is added to the
inside mask.
• Normal - the embedded alpha is used to key the layer as
normal. It is added to Keylight’s screen matte and can be
useful if requiring complicated multi-shaped masks to
rotoscope out garbage.
Inside Mask Tip
An alternative and very powerful use of the Source Alpha
option is to provide a solid inside mask pass-through in
multipass keying. In other words you can use Keylight to pull
a really harsh eroded matte that can be used to stop print
through in a second key that concentrates on the edges.
Print through is where the background shows through the
foreground in a composite. Here’s how you do it.
1. Apply Keylight to your footage and pick the screen colour.

Source Alpha
ADVANCED KEYING 43
2. Using Clip White, Clip Black and Screen Shrink/Grow while
viewing the Screen Matte, get a very harsh eroded matte as
shown in Figure 53.
3. Switch the View to Intermediate Result to pass through the
RGB channels unaffected with the screen matte in the alpha
channel. It looks a bit odd but don’t worry.
4. Now apply a second Keylight and pick the screen colour as
normal. Looking at the Status display as shown in Figure 54 you
should be able to see the background showing through the
foreground white areas.
Figure 53. Highly eroded matte.
Figure 54. Status for default key showing foreground
transparency.

ADVANCED KEYING
44
Colour Correction
5. To fix this we’ll use the harsh matte we pulled in the first key.
In the Inside Mask group, switch Source Alpha from Ignore to
Add To Inside Mask. The result is shown in Figure 55.
6. With a good foreground, you can now concentrate on pulling a
subtle key for the edges without worrying about the
background showing through the foreground. You may also
need to use a very rough garbage mask to improve the
background particularly for unevenly lit screens.
Colour Correction The Colour Correction parameters allow you to modify the
foreground colours in your composite. In particular, reflected
blues and greens from the screen can be suppressed.
Saturation - this control will increase or decrease the
colour saturation of the image, making colours more or less
intense.
Contrast - the contrast is the ratio of brightest tones to the
darkest. Increase this value for a contrasty image and
decrease it to wash it out.
Brightness - the brightness equates to the overall
Figure 55. Status showing improved foreground as a result
of adding the harsh matte from the first key.

Edge Colour Correction
ADVANCED KEYING 45
luminance of the image. Increase this value to make the
image lighter and decrease this value to make it darker.
Colour Suppression
Suppress - this controls colour suppression in the image.
You can choose to remove a specific primary, either Red,
Green, Blue or their complements, Cyan, Magenta or Yellow.
For green screens you may find it helpful to suppress green.
Suppression Balance - determines what to reduce the
suppressed component to. If set to 0%, it will be the smallest
of the other two components, if set to 100% it will be the
largest of the other two components. Otherwise, it will be to
a balanced average.
Suppression Amount - determines how strongly you want
to reduce the indicated component.
Colour Balancing
These controls are used to alter the colour balance of the
image. Choose a hue and saturation (either via the sliders or
the colour balance wheel) to shift the entire colour balance
of the image.
Edge Colour
Correction
The Edge Correction parameters allow you to colour correct
edges to seat the composite into the background. To see the
areas considered an edge that you will be affecting, select
the Colour Correction Edges from the View menu.
Enable Edge Colour Correction - use this option to

ADVANCED KEYING
46
Edge Colour Correction
separately colour correct edges of the image independently
from the overall colour correction.
Edge Hardness - this determines how strongly to blend
between the edge correction and the main correction.
Edge Softness - this will soften the region considered to be
the edge by this amount (in pixels).
Edge Grow - this will grow the region considered to be the
edge by this amount (in pixels).
Saturation - these controls determine how much to scale the
saturation of the image.
Contrast - this control increases/decreases the contrast on
the region considered to be the edge.
Brightness - this control brightens the region considered to
be the edge.
Edge Colour Suppression
Controls the colour suppression in the image.
Suppress - Choose to completely remove a specific primary,
either Red, Yellow, Green, Blue or their components, Cyan,
Magenta or Yellow.
Suppression Balance - determines what to reduce the
suppressed component to. If set to 0%, it will be the smallest
of the other two components, if set to 100% it will be the
largest of the other two components. Otherwise, it will be to
a balanced average.

Source Crops
ADVANCED KEYING 47
Suppression Amount - determines how strongly you want
to reduce the indicated component.
Colour Balancing
These controls are used to alter the colour balance of the
image edges. Choose a hue and saturation (either via the
sliders or the colour balance wheel) to shift the entire colour
balance of the image.
Source Crops The Source Crops enable you to quickly cut out lighting rigs
or other unwanted elements using vertical and horizontal
lines.
Keylight requires access to source pixels that lie off the edge
of the source image. The cropping controls provide access to
all the controls required for specifying how pixels are
treated at these edges and where they appear. The built-in
crop controls are also useful for removing unwanted black
pixels at the edge of video footage.
X Y Method - determines the behaviour of the image at the
left and right crop boundaries. Four edge methods are
supplied:
• Colour - fills the area between the crop line and the edge
with the Crop Colour.
• Reflect - reflects pixels about the current crop line. In
other words, it copies pixels from the other side of the
current crop line into the area between the current crop
line and the screen edge.
• Repeat - copies pixels on the crop boundary to the screen
edge.

ADVANCED KEYING
48
Source Crops
• Wrap - copies pixels from the area between the opposite
crop line and its screen edge to the area between the
current crop line and its screen edge.
Note Horizontal and vertical crop boundaries can have different edge
methods, Cropping is often used to remove unwanted pixels at the
edge of an image. If a video clip is digitized badly you may get
black edges left and right. These can be easily removed by moving
the vertical crops and setting the edge method to Reflect.
Edge Colour - sets the fill colour used when the edge method
is set to Colour.
Edge Colour Alpha - sets the fill colour transparency.
Left, Right, Top, Bottom - use these controls to set the crop
positions. Lines will be overlaid in the display enabling you to
set the various positions by eye.
Note The position of the crop lines can be changed by clicking and
dragging them directly on the screen.

Introduction
TUTORIAL 49
TUTORIAL
Introduction We have included several tutorials with example images that
you can use to practice Keylight.
• Tutorial 1: Simple Key
• Tutorial 2: Fine Tuning a Key
• Tutorial 3: Extreme Blue Spill
• Tutorial 4: A Red Green Screen
• Tutorial 5: Inside & Outside Masks
Example Images The tutorial images referred to in this chapter can be
downloaded from our web site www.thefoundry.co.uk.
Tutorial 1: Simple
Key
Using the blue screen clip from The Saint, you will composite
the actor over the background. You will learn how to:
• Apply Keylight to a layer.
• Pick the Screen Colour.
• View the Final Result.
The clips you will need for this task are called SaintFG.tif and
SaintBG.tif, pictures courtesy of CFC and Paramount British
Pictures Ltd. for the film The Saint. You should import them

TUTORIAL
50
Tutorial 1: Simple Key
into After Effects and create a new composition containing
the blue screen of Elizabeth Shue layered over the road.
Figure 56 is the blue screen foreground that should be
composited over the background shown in Figure 57.
Figure 56. Blue Screen - saint.tif
Figure 57. Background - road.tif

TUTORIAL 51
1. Create a new composition using SaintFG.tif and
SaintBG.tif, layer the clips with the blue screen over the
background as shown in Figure 58.
2. Select the blue screen clip (SaintFG.tif) in the Schematic
window and apply Keylight from the Effect - Keying menu.
See Figure 59.
Figure 58. Screen Shot showing Saint blue screen.
Figure 59. Apply Keylight from the Effect - Keying menu.

TUTORIAL
52
3. The Keylight parameters are shown in Figure 60.
4. Select the Screen Colour eye dropper and click on the blue
screen in the composition window. A good place to pick is
the blue from the back windscreen as this has no
reflections. See Figure 61.
5. That’s it. In many cases this is all you will need to do to
perform a key, since selecting the screen colour creates a
Figure 60. Keylight Parameters.
Figure 61. Pick the blue from the back windscreen.

TUTORIAL 53
matte and despills the foreground. The final composite is
shown in Figure 62.
There are a couple of extra steps that can be taken to fine
tune this key and these are discussed in the next tutorial on
page 54.
Figure 62. Final composite.

TUTORIAL
54
Tutorial 2: Fine Tuning a Key
Tutorial 2: Fine
Tuning a Key
Using the images from the film The Saint, you will learn how
to fine tune the key pulled in Tutorial 1. You will learn how
to:
• Use Status to judge the quality of the key.
• Use the Screen Gain to improve the background.
• Use the Despill Bias to remove more blue spill.
1. Create a new composition using SaintFG.tif and
SaintBG.tif. Apply Keylight to the blue screen layer. Select
the Screen Colour eye dropper and click on the blue
screen in the composition window.
Note These steps were covered in greater detail in the previous chapter.
2. Before we do anything else we need to look at the quality
of the key so far. On first inspection, the composite looks
pretty good, but it’s hard to judge. To see any potential
problems more clearly, switch to the Status view as
shown in Figure 63. Here we can see that the windscreens
are a mixture of black and grey pixels. The black pixels
tell us that pure background will be seen here in the final
composite. The grey pixels tell us that there will be a mix
of foreground and background pixels. What we want is a
clean background showing through the windows, but with
Figure 63. Status showing grey pixels in the background.

Tutorial 2: Fine Tuning a Key
TUTORIAL 55
some reflections in the side window preserved. In other
words we need mostly black pixels with a few grey ones.
3. Figure 64 on page 55 shows the Status view that we’re
aiming for. The background has been cleaned up and we
still have some reflections in the side window. To get this
you should increase the Screen Gain from 100 to 112.
4. Finally, if you look closely at the composite you will see a
tiny amount of blue spill on the woman’s hand and in her
hair. This was from reflected light from the blue screen.
Pick skin tones for the Despill Bias to remove it.
Figure 64. Improved background with Screen Gain.
Figure 65. Final Composite.

TUTORIAL
56
Tutorial 3: Extreme Blue Spill
Tutorial 3: Extreme
Blue Spill
This is a really interesting clip from the film Merlin. The
results with Keylight are certainly not perfect, indeed it is
unlikely that you will ever end up with a truly realistic
looking shot. However, there are some interesting things to
observe. You will learn how to:
• Reduce the blue spill using Screen Balance and Despill
Bias.
• Improve the foreground opacity using Alpha Bias.
1. Load the MerlinBlueFG.tif (Figure 66) and MerlinBlueBG.tif
clips and apply Keylight.
2. Pick the Screen Colour using the eye dropper.
Pick a pure blue pixel away from the hair.
Figure 66. A tricky blue screen.
Figure 67. Serious blue spill.

TUTORIAL 57
3. Increase the Screen Gain from 100 to 105. This will clean
up a little of the background.
4. Alter the Screen Balance from 95 to 0 as shown in
Figure 68. This step is a bit subjective, but improves the
blue spill.
5. Now let’s try and get rid of that blue spill. switch off Lock
Biases Together and pick skin tones for the Despill Bias.
When you do this the image and the screen colour will
have the blue component scaled up before the key is
pulled so that more blue is removed.
Figure 68. Adjust the Screen
Balance
Figure 69. Despill Bias.

TUTORIAL
58
6. You will notice that Miranda Richardson’s face now has a
number of blue highlights, due to the transparency, that
we should fix. The best way to do this is by drawing a
spline round the face as shown in Figure 70 and using it
as an Inside Mask. Refer to your After Effects guide for
more information on masks, however, select the pen tool,
draw a bezier spline around the face on frame 1 (Mask 1),
switch this mask off () then in keylight set the Inside Mask
to Mask 1 and SOurce to None. You should also soften
Figure 70. Inside Mask spline.

TUTORIAL 59
the mask slightly by setting the Inside Mask Softness to
5.
7. To remove the blue highlights on the cheeks (Figure 72)
you need to set the Replace Method to Soft Colour rather
than Source.
Figure 71. Switch the Mask off.
Figure 72. Replace - Source. Figure 73. Replace - Soft Colour.

TUTORIAL
60
8. View Final Result as shown in Figure 74.
Figure 74. Final Key.

Tutorial 4: A Red Green Screen
TUTORIAL 61
Tutorial 4: A Red
Green Screen
Using the images from the film Executive Decision, you will
learn how to pull a key from a poor green screen using the
Despill Bias control. You will learn how to:
• Pick the Screen Colour.
• Use Despill Bias and Alpha Bias.
• Produce a final composite.
The images you will need for this tutorial are called ExecFG.
1. Load the pictures ExecFG.tif (Figure 75) and ExecBG.tif.
Apply Keylight. The foreground image is actually a green
screen shot although it doesn’t look it. If you analyse the
pixels it’s slightly more red than green. To key this we’ll
have to fool Keylight.
2. Pick the Screen Colour. You should go for the slightly
darker green patch to the left of the pilot. Although feel
free to experiment picking different parts of the green
Figure 75. Poor Green Screen.

TUTORIAL
62
screen. The initial selection gives the result shown in
Figure 76.
3. To fix this we need to tell Keylight to scale down the red
component to make the green the most dominant so that
it keys correctly. To do this pick colours from the mask
for both the Despill Bias and Alpha Bias. The result is
shown in Figure 77.
Figure 76. Default key.
Figure 77. Despill Bias and Alpha Bias.

TUTORIAL 63
4. If you look closely, the background and foreground needs
cleaning up. Figure 78 shows the Status View. We will use
the Screen Matte tools to make the cockpit windows black
and the pilot white.
5. Increase Clip Black to 20 to remove some of the
foreground showing through the background. Decrease
Clip White to 70 to improve the opacity of the
foreground. Increase Screen Softness to 1, Screen Despot
Black to 2 and Screen Despot White to 2.
6. Use the Screen Matte Replace Method to pull some of the
original image through the composite. This improves the
Figure 78. Status View.
Figure 79. Composite.

TUTORIAL
64
apparent graininess in the foreground. Figure 80 shows
the differences.
Figure 80. Close up view. The left image has Replace Method
set to Source. The right image has Replace Method set to
None.

Tutorial 5: Inside & Outside Masks
TUTORIAL 65
Tutorial 5: Inside &
Outside Masks
Using the 16 bit blue screen test card image you will learn
how to:
• Use Inside and Outside Masks.
• Use the Replace Method to put back keyed out colours.
• Process the Screen Matte.
The clips you will need for this task are called TestCard.cin
and ColourGrid.cin
1. Start After Effects. Create a new 16 bit workspace.
Import the pictures TestCard.cin (Figure 81) and Colour-
Grid.cin and put them into the composition layering the
blue screen over the colour grid.
Figure 81. Test Card.

TUTORIAL
66
2. Apply Keylight to the blue screen layer and pick the blue
from the image. Keylight will create a matte and despill
the foreground as shown in Figure 82.
3. To remove the garbage around the subject we will use an
outside mask. Using After Effects’s masks, draw a spline
around the person and test cards. This will be called Mask
1 by default. This is shown as the yellow line in Figure 83.
In the Time Layout window twirl open the TestCard layer
and Masks sub-layer and set the compositing mode from
Add to None.
Figure 82. Basic Key.
Figure 83. Outside Mask.

TUTORIAL 67
4. In Keylight, check that the Outside Mask to Mask 1 and
switch Invert on or you’ll be removing the person rather
than the unwanted pixels at the screen edges.
5. You will have noticed in Figure 84 the "dirt" around the
subject’s head. Clearly we have to improve the key. You
can also see the faults in the matte if you view the Status
as shown in Figure 85.
Figure 84. Outside Mask.
Figure 85. Status View.

TUTORIAL
68
6. Increase the Screen Gain to 110. This cleans up some of
the background as shown in Figure 86.
7. Sections 7 to 10 will cover the changes to the Screen
Matte that will improve the key. In the Screen Matte
parameter area, decrease the Clip White from 100 to 70.
This will improve the foreground as shown in Figure 87.
However, you will notice in the composite that the edges
have become a little hard. We can fix this using the Clip
Rollback and Screen Softness.
Figure 86. Increase Screen Gain.
Figure 87. Clip White.

TUTORIAL 69
8. Increase the Clip Rollback to 3 and the Screen Softness to
1. It’s also worth trying to improve the key around the
spiky flowers with a sub-pixel erode of the edge. Change
Screen Grow/Shrink to -0.5.
9. To remove the foreground spots increase Screen Despot
Black to 1. The result is shown in Figure 89.
10.The composite is shown in Figure 90. You will see that
the colours of the colour swatches have been altered by
Figure 88. Rollback and Softness.
Figure 89. Screen Despot Black.

TUTORIAL
70
the Keylight algorithm. This can be fixed with an Inside
Mask.
11.Draw a rough mask (Mask 2) around just the colour
swatches. Set the Inside Mask to Mask 2 and the Replace
Method to Source to pull back the original colours.
12.That’s it.
Figure 90. Composite.
Figure 91. Inside Mask and
Replace Method Source.

Release Notes
APPENDIX A 71
APPENDIX A
Release Notes This appendix describes the requirements, new features,
improvements over previous versions, fixed bugs and known
bugs and workarounds in Keylight.
Keylight 1.2v8 This is a maintenance release of Keylight to fix a bug. The
version of Keylight that ships with AE CS3 Professional is
Keylight 1.2v5.
Requirements
Adobe After Effects CS3 Professional on Mac OS X or
Windows XP.
Release Date
January 2008
New Features
There are no new features.
Improvements
There are no improvements to existing features.
Fixed Bugs
1. Edge Colour Correction - BUG ID 3176 - colour correction
of the edges failed to work. This has been fixed.
Known Bugs and Workarounds
1. About Dialog - on Mac OS X only, launching the About
dialog from the Keylight banner and then clicking off the

APPENDIX A
72
Release Notes
dialog forces the dialog into the background under the AE
application window. Subsequent interaction with After
Effects would fail. To get round this, move the After
Effects applcation to one side to reveal the Keylight dia-
log underneath, then click on the dialog to close it.
2. Multiprocessing - BUG ID 194 - There is a
multiprocessing rendering bug shown up as half screen
renders. Only seen on Intel PCs with dual core. As a
workaround you could temporarily set the environment
variable FOUNDRY_MAX_PROCESSORS to 1.
Keylight 1.2v6 This is a maintenance release of Keylight to support AE CS3
on Mac and Win. The version of keylight that ships with AE
CS3 Professional is Keylight 1.2v5. This release fixes a
couple of bugs in that.
Requirements
Windows XP/Vista.
Release Date
5 July 2007
New Features
Improvements
Fixed Bugs
1. Adaptive Rendering - when scrubbing along the timeline
with adaptive rendering switched on, the screen would

Release Notes
APPENDIX A 73
freeze. An interrupt call was being treated as an error and
a redraw wasn’t called. This has been fixed.
2. About Dialog - clicking on the Keylight banner to show
the About dialog, caused the After Effects viewing
window to render black. This has been fixed by disabling
the ability to launch the dialog from the banner. Click on
the standard Adobe "About" text at the top of the plug-in
panel instead.
3. Snapshot - BUG ID 231 - snapshot button broken when
using Keylight with AE 7. This bug has been fixed in AE
CS3.
1. About Dialog - on Mac OS X only, launching the About
dialog from the Keylight banner and then clicking off the
dialog forces the dialog into the background under the AE
application window. Subsequent interaction with After
Effects would fail. To get round this, move the After
Effects applcation to one side to reveal the Keylight dia-
log underneath, then click on the dialog to close it.
2. Multiprocessing - BUG ID 194 - There is a
multiprocessing rendering bug shown up as half screen
renders. Only seen on Intel PCs with dual core. As a
workaround you could temporarily set the environment
variable FOUNDRY_MAX_PROCESSORS to 1.
Keylight 1.2v5 This is a maintenance release of Keylight to support After
Effects CS3. This version ships with AE CS3.
Requirements
Windows XP/Vista.

APPENDIX A
74
Release Notes
New Features
Improvements
Fixed Bugs
1. Internal version number incremented to enable licensing
to work correctly for the release version of CS3.
1. Multiprocessing - BUG ID 194 - There is a multiprocess-
ing rendering bug shown up as half screen renders. Only
seen on Intel PCs with dual core. As a workaround you
could temporarily set the environment variable
FOUNDRY_MAX_PROCESSORS to 1.
Known Bugs with After Effects and Workarounds
1. Snapshot - BUG ID 231 - snapshot buttons broken when
using Keylight with After Effects 7.0. If you apply Keylight
and snapshot the image, change some parameters and
recall that saved snapshot, it is displayed only for a frac-
tion of a second. As a workaround use the Shift-F5 and
F5 keys instead.
Effects CS3.
Requirements
Windows XP/Vista.

Release Notes
APPENDIX A 75
New Features
Improvements
Fixed Bugs
1. This version of Keylight was compiled against an updated
version of the After Effects SDK (7 March 2007).
F5 keys instead.
Effects CS3.
Release Date
Unreleased.

APPENDIX A
76
Release Notes
Requirements
Windows XP/Vista.
New Features
Improvements
Fixed Bugs
1. Loading old projects - BUG ID 923 - loading AE7 projects
that used Keylight 1.1 into AE8/CS3 with Keylight 1.2
would report a missing plug-in. This bug has been fixed.
F5 keys instead.
Keylight 1.2v2 This is a Windows only maintenance release of Keylight to fix
a bug.

Release Notes
APPENDIX A 77
Requirements
Adobe After Effects CS3 Professional on Windows XP/Vista
only.
New Features
Improvements
Fixed Bugs
1. SSE2 - BUG ID 801 - the previous version of Keylight was
compiled with a sse2 flag preventing it from working on
very old hardware running Windows. This version has
been recompiled with sse1 to fix this problem affecting a
minority of customers.
F5 keys instead.

APPENDIX A
78
Release Notes
Effects CS3.
Requirements
Windows XP/Vista.
New Features
1. FLEXlm license support for After Effects Standard.
2. Released as a universal binary for AE CS3 on Mac Intel
and PPC.
Improvements
1. The bias controls are now locked together by default.
2. The Keylight algorithm has been tweaked for improved
floating point handling.
3. An environment variable (FOUNDRY_MAX_PROCESSORS 1)
has been provided to switch off multi-processing as a
temporary workaround for Bug ID 194.
4. Keylight is now versioned by name. This allows multiple
versions of the plug-in to coexist on a single host.
5. 3GB Switch - the plug-ins have been compiled to take
advantage of extended memory available in this mode.
Fixed Bugs
1. Inside Mask, Source Alpha set to Add To Inside Mask.
When viewing the Status with the source alpha added to
the inside mask the combined mattes were not drawn on
screen even though the matte had been added. This has
been fixed so that the Status correctly shows these com-
bined mattes.

Release Notes
APPENDIX A 79
2. Source Crops - BUG ID 224 - changing the left crop value
from 0 when X Method is Colour, produces a rendering
error in the colour correction edges. This has been fixed.
3. Installer - BUG ID 223 - Keylight could only be installed
to the default directory. This has been fixed.
4. Colour Correction Clipping - BUG ID 225 - colour
correction of the foreground or edges is incorrectly
clipped between 0 and 1 for floating point images. This
has been fixed.
Keylight 1.1v1 This is a new release to support After Effects 7.0.
Requirements
Adobe After Effects 7.0 Professional on Mac OS X or PC.
Release Date
June 2005
New Features
1. Support for keying floating point images (32bpc).
Improvements
1. The Alpha and Despill Bias controls are now colour wid-
gets rather than sliders. This change extends the range of
shots that can be keyed.

APPENDIX A
80
Release Notes
2. The default edge method on the Source Crops has been
changed to Colour.
Fixed Bugs
There are no fixed bugs.
There are no known bugs.
Keylight 1.0v4 This is a maintenance release to fix a bug.
Requirements
Adobe After Effects 6.0 or 6.5 Professional on Mac OS X or
PC.
Release Date
8 September 2003
New Features
Improvements
1. Installer for Mac OS X changed to standard pkg format.
Plug-ins remain the same.
Fixed Bugs
1. BUG 354. On PC only, on selecting Edit>Purge>All After
Effects will crash. This has been fixed in this release.
1. BUG ID 99 - Keylight would sometimes render only half a
frame on multi-processor windows machines only on

Release Notes
APPENDIX A 81
After Effects 6.5 only. This did not affect After Effects
6.0 (or After Effects 7.0)
Keylight 1.0v3 This version is the full release and is supplied on the Adobe
After Effects 6.0 Professional CD.
Requirements
New Features
Improvements
Fixed Bugs
1. During a Keylight render, if a redraw of the After Effects
user interface occurs, possibly due to a screen saver or
window stowing, this may cause Keylight to crash. This
bug has been fixed.
2. BUG 346. If Keylight was copied and pasted between
compositions, After Effects will crash. This has been
fixed.
Keylight 1.0v2 Requirements
New Features

APPENDIX A
82
Release Notes
Improvements
1. A new parameter, "Normal", has been added to he Source
Alpha menu to allow embedded alpha to key the layer as
normal. This allows multi-shape masks to be used as gar-
bage mattes.
Fixed Bugs
There are no fixed bugs.
Keylight 1.0v1 Requirements
New Features
This section will describe new features in later versions.
Improvements
This section will describe improvements to existing features
in later versions.
Fixed Bugs
This section will describe fixed bugs in later versions.

End User License Agreement
APPENDIX B 83
APPENDIX B
IMPORTANT: BY INSTALLING THIS SOFTWARE YOU ACKNOWLEDGE THAT YOU HAVE READ THIS
AGREEMENT, UNDERSTAND IT AND AGREE TO BE BOUND BY ITS TERMS AND CONDITIONS. IF YOU
DO NOT AGREE TO THE TERMS OF THIS AGREEMENT DO NOT INSTALL, COPY OR USE THE SOFT-
WARE.
This END USER SOFTWARE LICENSE AGREEMENT (this "Agreement") is made by and between The
Foundry Visionmongers Ltd., a company registered in England and Wales, ("The Foundry"), and you,
as either an individual or a single entity ("Licensee").
In consideration of the mutual covenants contained herein and for other good and valuable consid-
eration (the receipt and sufficiency of which is acknowledged by each party hereto) the parties agree
as follows:
SECTION 1. GRANT OF LICENSE.
Subject to the limitations of Section 2, The Foundry hereby grants to Licensee a limited, non-trans-
ferable and non-exclusive license to install and use a machine readable, object code version of this
software program (the "Software") and the accompanying user guide and other documentation (col-
lectively, the "Documentation") solely for Licensee's own internal business purposes (collectively, the
"License"); provided, however, Licensee's right to install and use the Software and the Documenta-
tion is limited to those rights expressly set out in this Agreement.
SECTION 2. RESTRICTIONS ON USE.
Licensee is authorized to use the Software in machine readable, object code form only, and Licensee
shall not: (a) assign, sublicense, transfer, pledge, lease, rent, share or export the Software, the Doc-
umentation or Licensee's rights hereunder; (b) alter or circumvent the copy protection mechanisms in
the Software or reverse engineer, decompile, disassemble or otherwise attempt to discover the
source code of the Software; (c) modify, adapt, translate or create derivative works based on the
Software or Documentation; (d) use, or allow the use of, the Software or Documentation on any
project other than a project produced by Licensee (an "Authorized Project"); (e) allow or permit any-
one (other than Licensee and Licensee's authorized employees to the extent they are working on an

APPENDIX B
84
Authorized Project) to use or have access to the Software or Documentation; (f) copy or install the
Software or Documentation other than as expressly provided for herein; or (g) take any action, or
fail to take action, that could adversely affect the trademarks, service marks, patents, trade secrets,
copyrights or other intellectual property rights of The Foundry or any third party with intellectual
property rights in the Software (each, a "Third Party Licensor"). Furthermore, for purposes of this
Section 2, the term "Software" shall include any derivatives of the Software.
Licensee shall install and use only a single copy of the Software on one computer, unless the Soft-
ware is installed in a "floating license" environment, in which case Licensee may install the Software
on more than one computer; provided, however, Licensee shall not at any one time use more copies
of the Software than the total number of valid Software licenses purchased by Licensee.
Furthermore, the Software can be licensed on an "interactive" or "non-interactive" basis. Licensee
shall be authorized to use a non-interactive version of the Software for rendering purposes only
(i.e., on a CPU, without a user, in a non-interactive capacity) and shall not use such Software on
workstations or otherwise in a user-interactive capacity. Licensee shall be authorized to use an
interactive version of the Software for both interactive and non-interactive rendering purposes, if
available.
Finally, if the Software is an "Educational Version," Licensee may use it only for the purpose of train-
ing and instruction, and for no other purpose. Educational Versions of the Software may not be used
for commercial, professional or for-profit purposes.
SECTION 3. BACK-UP COPY.
Notwithstanding Section 2, Licensee may store one copy of the Software and Documentation off-
line and off-site in a secured location owned or leased by Licensee in order to provide a back-up in
the event of destruction by fire, flood, acts of war, acts of nature, vandalism or other incident. In no
event may Licensee use the back-up copy of the Software or Documentation to circumvent the usage
or other limitations set forth in this Agreement.
SECTION 4. OWNERSHIP.
Licensee acknowledges that the Software and Documentation and all intellectual property rights
relating thereto are and shall remain the sole property of The Foundry and the Third Party Licensors.
Licensee shall not remove, or allow the removal of, any copyright or other proprietary rights notice
included in and on the Software or Documentation or take any other action that could adversely
affect the property rights of The Foundry or any Third Party Licensor. To the extent that Licensee is
authorized to make copies of the Software or Documentation under this Agreement, Licensee shall

APPENDIX B 85
reproduce in and on all such copies any copyright and/or other proprietary rights notices provided in
and on the materials supplied by The Foundry hereunder. Nothing in this Agreement shall be deemed
to give Licensee any rights in the trademarks, service marks, patents, trade secrets, copyrights or
other intellectual property rights of The Foundry or any Third Party Licensor, and Licensee shall be
strictly prohibited from using the name, trademarks or service marks of The Foundry or any Third
Party Licensor in Licensee's promotion or publicity without The Foundry's express written approval.
SECTION 5. LICENSE FEE.
Licensee understands that the benefits granted to Licensee hereunder are contingent upon Lic-
ensee's payment in full of the license fee payable in connection herewith (the "License Fee").
SECTION 6. TAXES AND DUTIES.
Licensee agrees to pay, and indemnify The Foundry from claims for, any local, state or national tax
(exclusive of taxes based on net income), duty, tariff or other impost related to or arising from the
transaction contemplated by this Agreement.
SECTION 7. LIMITED WARRANTY.
The Foundry warrants that, for a period of ninety (90) days after delivery of the Software: (a) the
machine readable electronic files constituting the Software and Documentation shall be free from
errors that may arise from the electronic file transfer from The Foundry and/or its authorized
reseller to Licensee; and (b) to the best of The Foundry's knowledge, Licensee's use of the Software
in accordance with the Documentation will not, in and of itself, infringe any third party's copyright,
patent or other intellectual property rights. Except as warranted, the Software and Documentation
is being provided "as is." THE FOREGOING LIMITED WARRANTY IS IN LIEU OF ALL OTHER WARRAN-
TIES OR CONDITIONS, EXPRESS OR IMPLIED, AND The Foundry DISCLAIMS ANY AND ALL IMPLIED
WARRANTIES OR CONDITIONS, INCLUDING, WITHOUT LIMITATION, ANY IMPLIED WARRANTY OF
TITLE, NON-INFRINGEMENT, MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE,
REGARDLESS OF WHETHER The Foundry KNOWS OR HAS REASON TO KNOW OF LICENSEE'S PARTIC-
ULAR NEEDS. The Foundry does not warrant that the Software or Documentation will meet Lic-
ensee's requirements or that Licensee's use of the Software will be uninterrupted or error free. No
employee or agent of The Foundry is authorized to modify this limited warranty, nor to make addi-
tional warranties. No action for any breach of the above limited warranty may be commenced more
than one (1) year after Licensee's initial receipt of the Software. To the extent any implied warran-

APPENDIX B
86
ties may not be disclaimed under applicable law, then ANY IMPLIED WARRANTIES ARE LIMITED IN
DURATION TO NINETY (90) DAYS AFTER DELIVERY OF THE SOFTWARE TO LICENSEE.
SECTION 8. LIMITED REMEDY.
The exclusive remedy available to the Licensee in the event of a breach of the foregoing limited war-
ranty, TO THE EXCLUSION OF ALL OTHER REMEDIES, is for Licensee to destroy all copies of the
Software, send The Foundry a written certification of such destruction and, upon The Foundry's
receipt of such certification, The Foundry will make a replacement copy of the Software available to
Licensee.
SECTION 9. INDEMNIFICATION.
Licensee agrees to indemnify, hold harmless and defend The Foundry and The Foundry's affiliates,
officers, directors, shareholders, employees, authorized resellers, agents and other representatives
(collectively, the "Released Parties") from all claims, defense costs (including, but not limited to,
attorneys' fees), judgments, settlements and other expenses arising from or connected with the
operation of Licensee's business or Licensee's possession or use of the Software or Documentation.
SECTION 10. LIMITED LIABILITY.
In no event shall the Released Parties' cumulative liability to Licensee or any other party for any loss
or damages resulting from any claims, demands or actions arising out of or relating to this Agree-
ment (or the Software or Documentation contemplated herein) exceed the License Fee paid to The
Foundry or its authorized reseller for use of the Software. Furthermore, IN NO EVENT SHALL THE
RELEASED PARTIES BE LIABLE TO LICENSEE UNDER ANY THEORY FOR ANY INDIRECT, SPECIAL, INCI-
DENTAL, PUNITIVE, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING DAMAGES FOR LOSS
OF BUSINESS OR LOSS OF PROFITS) OR THE COST OF PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES, REGARDLESS OF WHETHER THE RELEASED PARTIES KNOW OR HAVE REASON TO KNOW
OF THE POSSIBILITY OF SUCH DAMAGES AND REGARDLESS OF WHETHER ANY REMEDY SET FORTH
HEREIN FAILS OF ITS ESSENTIAL PURPOSE. No action arising out of or related to this Agreement,
regardless of form, may be brought by Licensee more than one (1) year after Licensee's initial receipt
of the Software; provided, however, to the extent such one (1) year limit may not be valid under
applicable law, then such period shall limited to the shortest period allowed by law.

APPENDIX B 87
SECTION 11. TERM; TERMINATION.
This Agreement is effective upon Licensee's acceptance of the terms hereof (by clicking on the
"Accept" button) and Licensee's payment of the License Fee, and the Agreement will remain in effect
until termination. If Licensee breaches this Agreement, The Foundry may terminate the License
granted hereunder by notice to Licensee. In the event the License is terminated, Licensee will either
return to The Foundry all copies of the Software and Documentation in Licensee's possession or, if
The Foundry directs in writing, destroy all such copies. In the later case, if requested by The
Foundry, Licensee shall provide The Foundry with a certificate signed by an officer of Licensee con-
firming that the foregoing destruction has been completed.
SECTION 12. CONFIDENTIALITY.
Licensee agrees that the Software and Documentation are proprietary and confidential information
of The Foundry and that all such information and any communications relating thereto (collectively,
"Confidential Information") are confidential and a fundamental and important trade secret of The
Foundry. Licensee shall disclose Confidential Information only to Licensee's employees who are
working on an Authorized Project and have a "need-to-know" such Confidential Information, and
shall advise any recipients of Confidential Information that it is to be used only as authorized in this
Agreement. Licensee shall not disclose Confidential Information or otherwise make any Confidential
Information available to any other of Licensee's employees or to any third parties without the
express written consent of The Foundry. Licensee agrees to segregate, to the extent it can be rea-
sonably done, the Confidential Information from the confidential information and materials of others
in order to prevent commingling. Licensee shall take reasonable security measures, which such mea-
sures shall be at least as great as the measures Licensee uses to keep Licensee's own confidential
information secure (but in any case using no less than a reasonable degree of care), to hold the
Software, Documentation and any other Confidential Information in strict confidence and safe cus-
tody. The Foundry may request, in which case Licensee agrees to comply with, certain reasonable
security measures as part of the use of the Software and Documentation. Licensee acknowledges
that monetary damages may not be a sufficient remedy for unauthorized disclosure of Confidential
Information, and that The Foundry shall be entitled, without waiving any other rights or remedies, to
such injunctive or equitable relief as may be deemed proper by a court of competent jurisdiction.
SECTION 13. INSPECTION.
Licensee shall advise The Foundry on demand of all locations where the Software or Documentation
is used or stored. Licensee shall permit The Foundry or its authorized agents to inspect all such
locations during normal business hours and on reasonable advance notice.

APPENDIX B
88
SECTION 14. NONSOLICITATION.
Licensee agrees not to solicit for employment or retention, and not to employ or retain, any of The
Foundry's current or future employees who were or are involved in the development and/or creation
of the Software.
SECTION 15. U.S. GOVERNMENT LICENSE RIGHTS.
The Software, Documentation and/or data delivered hereunder are subject to the terms of this
Agreement and in no event shall the U.S. Government acquire greater than RESTRICTED/LIMITED
RIGHTS. At a minimum, use, duplication or disclosure by the U.S. Government is subject to the appli-
cable restrictions of: (i) FAR §52.227-14 ALTS I, II and III (June 1987); (ii) FAR §52.227-19 (June
1987); (iii) FAR §12.211 and 12.212; and/or (iv) DFARS §227.7202-1(a) and DFARS §227.7202-3.
The Software is the subject of the following notices:
* Copyright (c) 2007 The Foundry Visionmongers, Ltd.. All Rights Reserved.
* Unpublished-rights reserved under the Copyright Laws of the United Kingdom.
SECTION 16. SURVIVAL.
Sections 2, 4, 5, 6, 7, 8, 9, 10, 12, 13, 14, 15, 16, 17 and 18 shall survive any termination or expi-
ration of this Agreement.
SECTION 17. IMPORT/EXPORT CONTROLS.
To the extent that any Software made available hereunder is subject to restrictions upon export
and/or reexport from the United States, Licensee agrees to comply with, and not act or fail to act in
any way that would violate, the applicable international, national, state, regional and local laws and
regulations, including, without limitation, the United States Foreign Corrupt Practices Act, the
Export Administration Act and the Export Administration Regulations, as amended or otherwise
modified from time to time, and neither The Foundry nor Licensee shall be required under this Agree-
ment to act or fail to act in any way which it believes in good faith will violate any such laws or reg-
ulations.

APPENDIX B 89
SECTION 18. MISCELLANEOUS.
This Agreement is the exclusive agreement between the parties concerning the subject matter
hereof and supersedes any and all prior oral or written agreements, negotiations, or other dealings
between the parties concerning such subject. This Agreement may be modified only by a written
instrument signed by both parties. If any action is brought by either party to this Agreement against
the other party regarding the subject matter hereof, the prevailing party shall be entitled to recover,
in addition to any other relief granted, reasonable attorneys' fees and expenses of litigation. Should
any term of this Agreement be declared void or unenforceable by any court of competent jurisdic-
tion, such declaration shall have no effect on the remaining terms of this Agreement. The failure of
either party to enforce any rights granted hereunder or to take action against the other party in the
event of any breach hereunder shall not be deemed a waiver by that party as to subsequent enforce-
ment of rights or subsequent actions in the event of future breaches. This Agreement shall be gov-
erned by, and construed in accordance with English Law.
Copyright (c) 2007 The Foundry Visionmongers Ltd. All Rights Reserved. Do not duplicate.

APPENDIX B
90

A-Z
INDEX 91
INDEX
A-Z
A
Advanced Keying 23
B
Basic Keying 17
black pixels
See Status 20
blue pixels
See Status 35
blue spill 27
Brightness 44, 46
C
Clip Black 31
Clip Levels 31
Clip Rollback 36
Clip White 31
Colour Balancing 45, 47
Colour Correction 44
Colour Replacement 39
Colour Suppression 45
Computer Film Company 9
Contrast 44, 46
Cropping 47
Crops 47
D
Despill Bias 20
Despot 38
E
Edge Colour Suppression 46
Edge Correction 45
End User License
Agreement 83
Erode 38
Example Images 49
eye dropper 17
F
Framestore-CFC 9
G
Getting Started 11
green pixels
See Status 35
grey pixels
See Status 20
Grow 38
I
Images
Downloadable examples 49
Inside Masks 40
Installation
Windows 5, 6
L
Licensing 6
M
Matte
Combined Matte 33
Erode 38
Grow 38
Processing 36
Rollback 36
Screen Matte 33, 36
Shrink 38
Status 33
O
Outside Masks 40
R
red pixels
See Status 35
Release Notes 71
Render Controls
Colour Correction Edges 33
Combined Matte 33
Corrected Source 32
Final Result 33
Inside Mask 33
Intermediate Result 33
Outside Mask 33
Screen Matte 33
Source 32
Source Alpha 32
Status 33
Replace Method 39
Requirements 71, 72, 73, 74,
75, 76, 78, 79, 80, 81,
82
Rollback 36
S
Saturation 44, 46
Screen Balance 26
Screen Colour 17, 23
Screen Matte 36
Shrink 38
Source Alpha 42
Status 19

INDEX
92
A-Z
Status View 33
Suppression 45, 46
T
The Foundry
About Us 8
Tutorial 49
images 49
Introduction 49
Tutorial 1 49
Tutorial 2 54
Tutorial 3 56
Tutorial 4 61, 70
Tutorial 5 65
V
View 18, 32
W
white pixels
See Status 20

Keylight ae user guide

More Related Content

What's hot (18)

Similar to Keylight ae user guide (20)

More from Francisco Berrizbeitia (20)

Keylight ae user guide