The maximum number of frames in a still-image sequence is 32,766.
If you need to work with a larger number of frames, then you need to separate them into two image sequences.
Thanks, I hadn't run into this before with long projects, though, maybe
because I had to move the projects using smaller drives, that they ended
up essentially pre-separated into chunks, so I didn't notice that limit.
I wonder if the 64 bit version of AfterEffects CS5 will remove that
I wonder if the 64 bit version of AfterEffects CS5 will remove that limitation?
Why should it? You are confusing things here (no offense). This has nothing to do with how much memory AE can handle or any of that, it's good old 16bit integer code that handles the numbering calculations. This is certainly an issue just as deep as the memory handling itself and bound to cause a ton of compatibility problems with older versions, so any change on that end will have to be weighed carefully before changing it. I wouldn't keep my hopes up for any soon-ish action on that end, as certainly it is not the highest priority for 99% of users that only ever handle short sequences...