Break your scene into smaller parts and render them individually,  Save as TIF or PNG then piece them together in Photoshop.  For example, there is absolutely no need for the background to be in there unless some of your figures are interacting with it in some way.  Even then, you should keep track of what is where and render only the parts that are absolutely necessary at one time.

It's the only way you will get a large, complex image without otherwise compromising render or texture quality.

Coppula eam se non posit acceptera jocularum.

My Store

My Gallery