Resolution of pictures hopping from iphoto to imovie to idvd So, I've got this pretty big (12 minutes, 3sec/slide) slide show. I may be done with it. I may not.

The show is composed of ten iPhoto-11 slideshows. Each one was set up 4:3, then exported, with the kind advice of Nathan in another question to specify H.264, 2048 bit rate, and the second-highest resolution (my pick on the theory that I was not going to be driving an HDTV, just a relatively ordinary projector).

Imported into iMovie-11 at 30fps, arranged, decorated with music, exported to via the share menu iDVD. Didn't touch anything in iDVD. just pushed the burn button.

Inserted resulting disk into nice new-ish dvd player with 30" LCD TV, 720 resolution. The pictures have a very visible structure of being built of little squares.

I dont' see artifacts in full-screen preview in iPhoto, or in full-screen imovie preview on my macbook pro. (On my mini, it warns me that full resolution will be degradated, so the presence of them there is not a surprise). But the DVD has this problem.

edit

I discovered an option in iDVD to vary the 'encoding quality'. Moving that up to professional looked to me to make a notable improvement.

Ideas?
This issue may have been caused by a variety of issues:


The resolution was only at 720p.
iMovie compressed the movies.
The "encoding quality" may not have been up to par.


These programs have been updated significantly now, however. iPhoto has been replaced with Photos, and iDVD isn't supported now.