Hi,
If you are thinking of Cineform Neoscene pre-processing, it looks like this tool is extracting information from the MOV file in a smarter way than Vegas does, so it is able to get more bits of information for every pixel, leading to better quality video.
I must admit that I have personally skipped this step since I have upgraded to Vegas Pro 10 (I only bought Cineform because I got crashes with Vegas Pro 9 with my MOV files), saving conversion time and disk space.
If you dig a little on the support site of Cineform, you will find more explanations. Shortly said, it is related to the fact that it is able to mix information between neighboring pixels, which helps reconstructing more accurate data, whereas Vegas does not do it.
Another benefit is that the resulting AVI are easier to decode for Vegas, so the preview is slightly smoother than with MOV files.
Hope this helps,
Frédéric
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