Before anyone bites my head off about the topic, hear me out.
I was attempting to make a scene (keyword attempting), and it seems I was relying on the preview render a little bit to much for atmospheric work. I had what seemed to be a good red decay in the preview, and so I went with what looked good to me. However after my 8 hour render (no water, and seemingly low detail...another topic on its own imho), the atmosphere was extremely red. Just putting out the thought of seeing if this could possibly be fixed later on, or if there is some kind of setting I need to set for a more accurate preview render.
as i know the 3d preview is based on opengl, have you got latest drivers installed and of course work with 32bit colours?
32bit colors, yes. Newest drivers, hehe probably not. Since I'm on 56k at the moment, those will have to wait for another week or so. Thanks for the advice though!
The optimal solution would be if the openGL view would respect the crop setting, so it could be much faster, tweaking could be a dream.
OpenGL issues should not affect the preview *accuracy* since it is actually based on the software renderer. Only the display of the preview involves OpenGL (it does not take advantage of modern 3D graphics hardware features for rendering).
As far as the accuracy of the preview, one big different is the preview doesn't include global illumination. You may instead want to rely on low detail normal renders, if necessary using the same GI settings as your final render, to get a better idea of how things will end up. If your final render will be 800x600 at detail 1 and GI of 2/2, you could do an 800x600 render at detail 0.1 with GI 2/2 in about 1/100th the time. This should still give you a pretty good idea of how the scene will look and will include GI calculations. A detail of 0.2 will be about the same as the max detail of the preview.