Where do I find the options to change the final render size?
Very top left of screen. File / Document Resolution
thanks chohole, I did find it but said file/document settings on my screen. I assume you need to set this before you start a scene, as I changed it on the scene I had already done and then rendered and only part of the scene was in the render.
No, I always compose my images on a working panel that I can see the whole of, and then change the doc res to what I want the finished image to be, but in the same ratio. Once the render has finished you can use the little hand (bottom right) to move around the render, and you will see that it has all rendered.
oh ok, thanks chohole :)