What I've been doing to get better resolution is simply zooming in and using print screen. I may zoom in to 1/4 of the model for example, take a screen shot, move to the next 1/4, take the screen shot again and so on until I'm done with all 4 sections. Each time after I print screen, I'd paste it to Paint.NET to crop and stitch them together. But you have to be careful and maintain the same amount of zoom, and the same model orientation when you move from one section to the next.
But I rarely ever need to do it, and I happen to be pretty good at using image editors so the amount of work involved doesn't really bother me.