I'm always wondering how can a space art piece so sharp like some here in DA (I can provide links).Sharp nebulae, sharp textured planets...I always render a planet in 3ds Max 3000x3000, but when I insert it into a space scene, it loses its "sharpness". Also the nebulae.
I paint sg, adding clouds, brushing out and belnding, experimenting, but it seems, it is not enough :D I have to experiment more.