What is the best way to generate a 360 degree sky backbrop so that I can have the camera follow an object.
What I mean is what would be the best way to set up a render to generate the backdrop to be used later?
should I render the scene from several different angles and use photoshop to combine them?
And what are good dimensions for a full 360 backdrop image.
what about an environment map?
what resolution will you be rendering at?
To generate your own custom spherical environment maps you’ll need to use a third party application to combine the images you’ve rendered with blender.
Although I’ve experienced some inaccuracies with this approach, one way that will work is to use BGC to create 6 images that can be mapped onto a cube and combine these into a spherical map.
Start with BGC [here] then combine the results into a vertical cross like so in GIMP 
After you’ve combined all 6 into a single image and exported take that image into HDR Shop [here] and perform a “Panoramic Transform” from a vertical cross to a Light Probe (Angular Map).
As I mentioned there are some innacuracies with the approach. Panotools will combine mirror ball images according to the talk around the net but at the moment I haven’t done the leg work on that approach. Basically you place a mirror ball at the center of the scene and take three pictures every 120 degrees then combine them together. At that point I’m not too sure what to do next.
For a simple 360 degree pano Panotools will work also but you get no sky or floor. Since you’ll be stretching the image across the entire sky you’ll need to use a decent resolution. 1000x1000 for each panel seems to be a good low end.
Check out the skymap thread here. It has info on how to make neat anglemaps (with some included in the thread.)
Haven’t had a look at that thread for a while. 
ReSPaM. Haha, good one. Thanks for the heads up.