On "the ark" if you start the level, and then end it right after you land (for comparison purposes), you can go into theater and look at the film.. Pull the Right trigger once to pause everything, Press "Y" to "float" your camera, and then just hover around to the back of the pelican that's following you. If you go in and look at the ODSTs sitting there, they're the same ones you've got pictured there, in the best lighting environment for them that I've seen so far.
Does everyone realize that you can "zoom" the camera in that mode too (by clicking your thumbstick)? I'm always amazed when folks want reference pics of Halo 3 stuff when they've got Xbox LIVE... I can fill the screen with just a corner of the Masterchief's visor. Then just go to your Bungie.net profile and look at your screenshots.. click on the thumbnail sized shot and see a larger version, click THAT one and it'll allow you to download an even larger version.
You don't even have to put it in your fileshare. You can have like 50 screenshots uploaded that way, although, reliably, I only count on 30 screenshots being uploaded, assuming I've deleted all my screenshots on the Xbox before I begin taking new ones. (to get to your xbox screenshots for deletion, just go to the settings (start button) and choose "screenshots", then choose "edit" (blue button) and delete... It's time intensive, but totally worth it.
As soon as you start seeing the error message when you save your screenshot (approaching screenshot limit), only SOME of the pics seem to upload at that point.
Also.. be sure you're connected to xbox live while taking the snapshots, or it won't upload anything.
(I know you probably know the camera controls and the online screenshots, Vrogy, that's just for the folks that don't know)