I'm rendering an image for the second time, - I had to fix some stuff on it. I'm rendering to disk, and I selected "superfine", and 1024x800 format.. but only 72 dpi. And this seems to take forever!! What exactly does the "superfine" do?

I just asked a question related to this in the "Posters" thread in regards to print resolution and resizing.

Superfine is just a different method of doing AA (Anti Aliasing) or 'jaggy removing'. Sf is much more crisp looking and decreases some of the artifacts created when rendering fine models, like grass or hair by taking more samples. In turn the render time is immense. i believe that superfine is really effect AA without all the options available and rendered at a low rpp.

I'll have to go have a look. :) I finally gave up. I'm render "normal" now, but with the same image format, and it's already 30%, whereas the "superfine" render only had done 5% in 4 hrs!

I usually use Superfine only with plop render and on small areas at a time.

well, superfine can actually save you time with certain scenes. Sometimes the default bryce antialiasing with scene's that have high frequency bump maps, reflection, and refraction takes forever, and it is faster to render at fine art AA because there is no AA pass at the end. My mage in my gallery, "hyperrealism" was rendered in superfine.

Yeah, the final AA pass can sometimes take longer than the entire pre process. I don't know if it can ever "save" you time, but you can be sure that in most cases you will get superior quality image for anywhere between 1.5 - 10x the render time.

Hmm... I get it.. The not "Antialiasing" Does explain it. My image has done the renderpasses, and is antialiasing now, and that sure takes time! :)

Antialiasing can take forever, and it doesn't always look good. I always use superfine or premium, but then my render times are hell LOL...

Superfine will help bring out, more complex type of textures even if further away from the camera. In the example see how the texture has better quality far away when using the 256 Rays Per Pixel. That being said, I will also admit to using Superfine AA rarely. Usually, I will plop render it, after rendering the whole scene on normal, I don't do many secenes where the whole scene would benefit from being completely rendered in Superfine AA. I will mostly use it, because it will also better define small objects in the background; grass blades, lengths of rope, etc. AgentSmith