The generally percieved wisdom is that shooting in HD and downconverting is preferential to shooting in SD. However, if you convert from HD to SD, you will only see a drop in quality, i.e. there will absolutely be no gain from downcoverting.
To summarise, the commonly held perception of the order of quality (assuming all other things are equal) is:
...and the next question will be - what is the best way to down convert?
They are many and varied. Some people are happy with dropping their footage on to an SD timeline and doing it that way. Most are not.
Some people are happy with exporting from FCP in HD and letting compressor do the conversion, while again, others are not.
Some people down convert in After Effects then send the resulting SD file to compressor for DVDs while others can't see any difference.
Personally I've looked at lots of different ways, and frankly I'm not entirely happy with any of them - not because they don't work, but because emotionally I hate the loss of quality in any/all the methods. Then I look at footage shot in native SD and it's pretty crap too.
So, the moral of this story is don't be too unhappy with the resulting SD video if you've been editing and used to viewing it all in HD. When it gets down to SD it's going to look worse than you hoped! :(
I use my camera to down scale, simply because it is the quickest and simplest way of doing it. I record in HD on a memory card, then copy the footage in real time onto the tape on the camera. This I think is easier and more reliable than using computers to do it.
I just wish my computer was up to editing HD and I had a BluRay burner.
bit of a thread hijack here, but if you edit in SD, and then replace your clips with HD versions, you get the best of both worlds. In CS4, I create a new HD timeline, copy the SD clips, then replace the clips in the bin. A bit time consuming, I must admit, but I,m sure you could either write a script in vegas, or use standard functionality I;ve been too obtuse to work out. Posted via Mobile Device
That sounds like good advice but I don't have a clue how to do it in Vegas. Also the MXK files are not compatible in Vegas without paying another couple of hundred dollars for a plug in. If I could figure out how to do it that would be great.