i think what is meant by higher resolution is actually higher oversampling, it is a method of creating anti-aliasing by (during the rendering process)rendering the picture larger then downsizing it to get smoother edges, so yes, you would end up with a picture with the same dpi as another set to the same resolution in the end. for web graphics i find 200 to 400 more than enough - you won't see any differneunless youzoom in uper close an, to high an oversample and you lose definition. i've just looked at your picture, i don't use uf so i don't know how that works but it looks like you imported a flame on a transparent background into uf and composited it there without any manipulation of the flame? personally i don't think a higher resolution would make that much difference to that flame, what you would get instead of the black pixel area is that area being more dense and grey. is it possible to select by colour (select all the black/grey bits) and delete/cut them in ultra fractal ? i would do that until i have nothing but the coloured part of the flame and then to intensify that flame layer it several times. that is a lot of postwork though and ideally you want to render flames which don't need that much work, probably the best way of doing that if you intend to xport the flame is to tweak (move the triangles) the flame on a light coloured background in apo, that way you can see all the background noise and minimise it before rendering.