Q: What is the difference between 8 bit and 32 bit Pixel Format in the Vegas Pro Project Property Settings ?
Answer: The bits is referring to Colour Depth - the more Bits equals greater colour depth.
Choose a setting from the drop-down list to indicate whether you want to perform video processing (compositing, scaling, previewing, rendering, and most video plug-ins) using 8-bit or 32-bit, floating-point arithmetic.
8-bit performs video processing using 8-bit arithmetic and in the video (studio RGB, or 16-235) color space.
32-bit floating point (video levels) performs video processing using 32-bit arithmetic and in the video color space.
32-bit floating point (full range) performs video processing using 32-bit arithmetic and in the full-range color space.
The 32-bit floating point settings allow greater precision for processing video, but require significantly more processing power than working with 8-bit video.
For everyday video from a consumer grade video camera or mobile phone, 8 bit is the setting you should use. The 32 bit settings are more for Professional Film makers using lots of Compositing Modes and FX with High Resolution video. The problem with 32 bit for home users on a regular computer, is that it will take a huge drain on your CPU resources and create more lag in the preview window.
32-bit floating point (video levels) is recommended when working with 10-bit YUV input/output or when using xvYCC/x.v.Color media.
When using 8-bit input/output, the 32-bit floating point (video levels) setting can prevent banding from compositing that contains fades, feathered edges, or gradients.
Video plug-ins and media generators that support floating-point processing are included in the 32-bit floating point folder in the Transitions, Video FX, Media Generators, Compositors, and Plug-In Manager windows.
If you're creating a 32-bit project, you can increase performance during editing and playback by using the 8-bit setting during editing and switching to 32-bit floating point (video levels) before rendering.
When you choose 32-bit floating point (full range) from the Pixel format drop-down list, you can choose a compositing gamma value.
1.000 (Linear): The default setting when you choose 32-bit floating point (full range) from the Pixel format drop-down list.
2.222 (Video): Processing in 8-bit video is always performed using a setting of 2.222.
For a full explanation of the technical differences, please refer to this article on Wikipedia.
*This information applies only to Vegas Pro and is not available as an option in Vegas Movie Studio Platinum.
Project Properties Window in Vegas Pro 11
Alternatives available - for most average users 8 bit is just fine