Setting the Graphics Processing Bit Depth
Depending on your system, you can specify the bit depth for images that are processed using the frame buffer in the graphics card. The bit depth affects the quality of the resulting clip. Images can be processed with 8-bit or 16-bit FP precision.
As a rule, if you are working with mixed resolutions and some clips are higher than 8-bit, you should select 16-bit FP graphics display. Even if you work only with 8-bit images, you can get better processed results with 16-bit FP graphics processing when transparencies, blending, and gradients are part of your effect. 16-bit FP graphics processing produces better results but takes longer.
Projects from previous versions of the application with a graphics bit depth higher than 8-bit are mapped to 16-bit FP in the 2009 release.
Also, if your output is ultimately an 8-bit format, having the best possible quality immediately prior to output produces the best results.
To set the graphics processing bit depth:
