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680 Chapter 20: Managing Scenes and Projects
•CMYKColor
•LabColor
•Multichannel
Non-Image Lay ers—Layers other than image layers
(for example, text layers) are not supported. In
Photoshop, you can “rasterize” a non-image layer
to make it an image.
Compositing Options—Compositing options
between image layers, wh ich require processing by
Photoshop, are not supported.
RLA Files
The RLA format is a popular SGI format that
supp orts the ability to include arbitrary image
channels. While setting up a file for output, if you
select RLA Image File from the list and click the
Setup button, you’ll go to the RLA setup dialog.
Once there, you can specify what channels (and
what format) you want to write out to the file.
See also
RPF Files (page 3–681)
Inter face
When RLA is the chosen output format, clicking
Render or Setup on the
Render Output File dialog
(page 3–8)
displaystheRLAImageFileFormat
dialog.
Standard Channels group
The standard channels are RGB color and the
alpha (transparency) channel.
Bi ts per Channel—Choose 8, 16, or 32 Floating
Point as the number of bits per channel. Default=8.
Store Alpha Channel—Cho ose whether to save the
alpha channel. Default=on.
Premulti ply Alpha—When on, premultiplies the
alpha channel. Default=on.
Premultiplying saves computation time if you
later use this image in compositing. For more
information, see
Premultiplied Alpha (page
3–1091)
.
Optional Channels group
For output RLA files, there are eight additional
channels that you can generate (and view in the
rendered frame window):
ZDepth—Displays Z-Buffer information in
repeating gradients from white to black. The
gradients indicate relative depth of the object in
the scene.
Material Ef fects—Displays the Effects Channel
used by materials assigned to objects in the scene.
The Effects Channel is a material property set in
the Material Editor and used during Video Post
compositing. Each Effects Channel ID is displayed
using a different random color.
Object—Displays the G-Buffer (page 3–1040)
Object Channel ID assigned to objects using the
Object Properties dialog. The G-Buffer ID is used
during Video Post compositing. Each G-Buffer ID
is displayed using a different random color.
UV Coordinates—Displays the range of UV
mapping coordinates as a color gradient. This
channel shows where mapping seams might occur.
Note: UV Coordinates w ill not be displayed on
objects that have the UVW Map Modifier applied