Genuine Fractals example from a realworld user :-) This is an image that was originally 1296x864 which I blew up to create a poster size image.

The increase is 602% (new res  5250x3500

I've attached screenshots of the 2 sizes the larger being the result of using GF.  The 3D part of it is relatively clear - enough for me to produce a print size, but some of the background is a little blurry but still not too bad.  

Gill