2008

In the Prefs panel, you can control whether or not specific parts of the lens
flare, such as the rays or the star are rendered by turning them on or off. You
can also control the axial transparency of the lens flare.
Interface
Affect Alpha Specifies whether or not the lens flare affects the alpha channel
of an image, when the image is rendered in a 32-bit file format. The alpha
channel is an extra 8 bits of color (256 colors) that indicate transparency in
an image. Alpha channels are used to composite one image seamlessly over
the top of another. If you want to composite a lens flare, or an image that
contains a lens flare, over the top of another image, enable this option. If you
are not rendering to a 32-bit file, do not enable this option.
Affect Z Buffer The Z-Buffer stores an object's distance from the camera. The
Z-Buffer is useful for optical effects such as fog. When this option is enabled,
the linear distance of the lens flare is recorded, and can be used in special
effects that make use of the Z-Buffer, for example, the
Focus on page 6670
effect. To use Focus with a lens flare, enable this option.
6654 | Chapter 20 Video Post