There is software (Adobe makes one, I can't remember it's name) that will auto-trace a simple black and white line drawing, but not continuous tone images. Alternately, the magnetic pen tool in photoshop does a mediocre job of tracing. Unfortunately, with continuous tone renders like from Bryce, I think you're stuck doing it the hard way. I'd also guess that it would be faster to render than to trace. If you insist on tracing, I'd start with lots of render masks and select them in Photoshop and convert the selections to paths. It may save a little time. There is also a Photoshop plugin called Genuine Fractals which promises to upsample raster images with minimal quality loss, but I've found that it makes little or no difference with Photoshop 5.5 and higher (never tried with lower versions). I frequently upsample images in Photoshop and get acceptable results in print -- especially ink jet and dye-sub prints -- without Genuine Fractals.