Re: Example 25i vs 50p
 

The special case of psF indicates a single Frame split into separate fields. You are correct in understanding that a typical recording has two fields separated temporally, in a psF recording a single Frame is split into two fields that can be reconstructed into a single Frame without any temporal separation.

Cheers,
GB

Re: Example 25i vs 50p
 

Understood. The interlace stream is acting as a carrier for the source progressive input whether its 30 fps or 24fps ( for NTSC as an example) with just different pulldowns that the NLE will use to reconstruct the source progressive file.

Ron Evans.