I'm using a Canon XL-H1 to shoot a band against a green screen. Has anyone gone down this road before and have a) any general tips, and b) can anyone suggest which is the better frame rate to shoot at? I'll be editing in After Effects.
As for general tips, there is tons of useful info already on the COW as greenscreening is an often discussed subject. Do searches using the keywords "greenscreen," "green screen," "chromakey," and "chroma key" and you will find lots of threads with good tips. The short list of tips are 1) make sure your background is perfectly evenly lit, 2) make sure the talent it lit completely independently from the background, and 3) minimize green spill onto the talent. Some people also like to 4) add a little bit of minus green gel to the talents' backlights. Again, a search will yield much more detailed info.
As for frame size, the title of your post asks "1080i or 720p?" That one's easy, because you are shooting with and XLH1. The H1 is a 1080 camera, you couldn't shoot 720 with it even if you wanted to... so, 1080.
As for frame rate, I'd say that just depends on the look that you are going for. 24p (or in Canon's case, 24f) is just going to give a completely different look then 60i. 24p is going to be much more filmic, 60i will be much more "videoy." Which look are you going for? Let that make the determination. Some people might say that one will key slightly better than the other, but either will yield acceptible keys, if the scene is properly lit for keying.
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