The H.264 version is the last format in my workflow. It gets recorded to tape from there.
To answer your questions…
1. Are you capturing HD or SD?
SD only
2. Does your captured media have these same banding issues?
The original betacam SP tapes that are used do not have this problem
3. Are there an frame rate conversions happening?
To my knowledge, the offices that use this go with 29.97 for the uncompressed file and also 29.97 for the Quick Time conversion to H.264
4. What is your captured frame rate?
29.97 frames per second, NTSC
5. What settings are you using to create your h.264?
I believe it is simply 29.97 FPS and on the “Better” or “Best” option for quality.
The uncompressed file is an AVI file and the H.264 codec conversion ends up making it Quick Time. Would this affect it? Perhaps Quick Time Pro does not handle AVI files very well?