Datasheet

FILE FORMATS
In addition to image types, several image file formats are available today. The most com-
mon is probably JPEG (Joint Photographic Experts Group), which is widely used on the
Internet for its small size and reasonable image quality. However, JPEGs are too com-
pressed and lossy (meaning they lose color detail when compared to the original) to be
used in most CG renders.
The main difference among file formats relates to how they store images. Some formats
compress the file to reduce file size; however, the greater the compression, the poorer the
image’s color.
The popular formats to render into from 3ds Max are TIFF (Tagged Image File For-
mat) and Targa (TGA). These file formats maintain a good 24-bit color depth using an
8-bit image file, are either uncompressed or hardly compressed (lossless compression), and
are frequently used for broadcast or video work. These formats also have an alpha channel,
giving you better control when you later composite images together.
To see an animation rendered in a file sequence of TIFFs, you will need to play them
back using a frame player, such as 3ds Max’s RAM Player, or you can compile them into a
movie file, such as a QuickTime file.
Your final image output format will depend on the project’s needs. If, for example, you
need to composite your CG together, you will need to output in a format that can be used
in your compositing or editing program. TIFF files are perhaps the best format to use as
they are widely compatible, store uncompressed color, and have an alpha channel.
MOVIE FILES
Animations can also be output to movie files such as AVI or QuickTime. These usually
large files are self-contained and hold all the images necessary for the animation that they
play back as frames. Like image files, movie files can be compressed to keep their sizes to a
minimum, but they suffer from quality loss as well.
3ds Max can render directly to an AVI or QuickTime movie file. This may seem like it
saves you the hassle of rendering out large sequences of image files. In reality, you shouldn’t
render directly to a movie file, at least for your final output. It is best to render a sequence of
files, because image sequences can easily be compiled into a movie file later using a program
such as Autodesk Combustion, Adobe After Effects, Premiere, or even QuickTime Pro.
Rendering to images is less risky than rendering to a movie. In addition to having a
sequence you can easily manipulate, you do not have to worry about crashing and losing
rendering time. Sometimes, your render will crash or your machine will freeze. If you
are rendering to a movie file when that happens, you’ll need to restart rendering from the
beginning, because you can’t append content to a half-rendered QuickTime. With a file
sequence render, you can simply pick up the render from the last good frame.
With a sequence, you also have the option of reordering the frames or easily adjusting a
few individual frames’ properties, such as hue or saturation, without affecting the entire
movie file.
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