1.) Overall I am wondering where I might find some documentation to understand the whole topic of codec_frame rates_Progressive_Interlaced choices related to quality and final outputs.
2) This subject came up as I was given EX3 footage to edit from 1080 30P source footage, and now I am hearing this was not a good choice if I am going out to DVD5, presumably 1080i (as I understand it).
My friend suggested that 1080 30P is not really a good choice to shoot in overall for anything.
It is important to shoot an appropriate frame rate for your intended end use. 30p is a good rate for webcast because it repeated each frame twice and makes it easy7 for the encoder to keep up. In addition, it's a good frame rate for feature news/doc on tv, as it has a somewhat film look vs. live video look of 60p or 60i. It's for this reason that CBS's 60 Minutes is shot at this rate.
For DVD's the favored rate is 24p, especially for long form like movies. This is because it uses on;y 40% of the stpace of 60p or 60i and you can fit a feature length program on the DVD.
Finally, 720/60p and 1080/60i are for a live tv look.
The real problem comes when there are multiple end uses or even unknown end use. 24p can be easily converted to 60i, although it will retain it's film like motion. 30 and 60 cannot be converted to 24p successfully, although there are "film look" processes that approximate the film motion.
One last thing to remember when choosing frame rates is to use a 180 degree (or half) shutter) when shooting 24 or 30p.