it depends on the format of the h264 you are using, and what you will be exporting to.
Remember: its always best to scale down then scale up. So you may want to open a dv project and downscale the h264 to fit.
Do you shoot fullscreen (4:3) or widescreen (16:9) with the DV cameras? Do you shoot 60i or 24p with the DV cameras? What format do you shoot with the T2i?
Basically, you'll want to use the lowest common denominator in most circumstances, which is DV for you. As long as your frame rates are the same between the DV cams and the T2i, just pick the DV preset that matches your DV footage, and scale the T2i footage down to fit. For DV, you have choices like:
DV NTSC Widescreen
DV 24P Widscreen
No need to convert anything; just drop everything in the sequence and edit away.
Thanks for the quick responses. I'll export to DVD files (MPEG2/aac), a 1080p .mov file, and a 720p .mov file. I shoot all widescren, all 30 fps. Sounds like the DV NTSC Widescreen would be the best sequence. Since this is my first time in Premiere CS5, how will I resize the T2i footage?
Are these DV cameras or HDV cameras? If DV, you're not going to have really great results creating HD output from SD source. If it's HDV, you don't want to use a DV sequence, but instead use a relevant HDV preset.
Ultimately, scaling standard definition to high-definition by any method is not optimal; the results are nowhere close to shooting in HD originally. In addition, it doesn't make much sense to scaled HD video down to SD for editing, only to scale it back up to HD for output. Clarify your source cameras for a better recommendation.
Premiere has a "scale to fit" option in the preferences; I don't recommend using this, as everything you drop into ANY timeline gets scaled, whether it's larger or smaller. You can scale to fit on an individual basis (right-click a clip), but the better way is to use the Scale parameter on a single clip, save that as a preset, and apply that to other instances of the T2i footage elsewhere in the sequence. Alternatively, you can copy the Motion effect (where Scale is located) and paste it to the other clips.
Sorry - I guess that would help! The two other cameras are Canon HV40s (HDV).
OK, so you can use an HD sequence; forget the DV recommendations.
Now, you need to be specific about which mode you're shooting in with each camera. The HDV cameras are 1440x1080, but you have the option of 30p or 60i (sometimes called 30i). Since the T2i only has one 30p mode (1920x1080, 30p), I'll assume that that's what you're shooting in, but please correct me if I'm wrong.
If all of this is true, I would use the "DSLR 1080p30 @ 29.97" preset in Premiere. This is the best common denominator with those footage choices. You could also use "HDV 1080p30" but I prefer to use square pixels (which is what the other preset uses) wherever possible.
No need to alter the dimension of any of the footage; it'll all drop in and fit perfectly. From there, you can export in all of the ways you want.
All of that is true. Thanks for walking through that with me!