My team is looking into shooting some scenes where there will be graphics comped in to make various surfaces (walls, handheld screens, etc) into display screens.
I've got a good grip on the graphics themselves, and the tracking needed to properly place and composite the elements. The biggest challenge will be pulling mattes on the foreground elements such as the people and hands that will be interacting with the screens.
I'm looking for some advice on the best way to shoot the plates in order to minimize slow and painstaking rotoscoping (welcome to the world, right?). I'm attaching an image that includes some reference stills from some well done videos from Corning and Microsoft found on you tube, and some test footage we shot in our lobby with a large plate of glass. I'd love to know how the crews in the reference videos shot their plates...I don't think against solid green since there is active reflections with the subjects...perhaps a glass surface with green behind it? I'd like to try using difference matte but as far as I can tell that is never the cleanest way to pull mattes.
If I have to roto, I've been learning Mocha for AE...I also worked with the roto brush but damn it seems slow. Any and all tips, reference, links to other tutorials would be greatly appreciated. Thanks in advance!
There are a number of ways you could tackle this and I guess it depends on a number of factors such as how much movement of the talent and / or the actor.
One method is to entirely shoot the talent against a green screen then backgrounds separately. Another would be to shoot talent against actual bg and perhaps put small green screen up where there is to be a lot of interaction. If the camera is moving you could use mocha to track and create a stabilised precomp to replace the bg in the green screen area (depending on amount of camera movement).
Rotoscoping is still an option using the rotobrush tool. You would work on just the areas needed. It's difficult to decide exactly which method without knowing all the parameters however, as you have hinted that the shoot is still in planning stages you could try some of these methods and see which gives the best results. In some circumstances you may find a combination may be better.
If the mocha route is to be used, google search mochaimport+ which is a very helpful script.