sci-fi game prop : vent
Another texturing exercise.
Blender direct paint + Gimp , a scratch/dirt map was painted in Blender , ao baked , normal map from hipoly , then Gimp to blend photo textures using the dirtmap and more painting.
Painting textures really is an art .. not a short list of tricks to learn quickly .Sure you need to learn that : but then a lot of practice .
Consider painted metal scratches : we all know it scratches on corners .. but the quality of the texture depends on training the eye for subtler details (and reproducing them):
There might be a coat of primer under the paint that wears out smoothly and fades (while paint chips away more sharply) , also around chipped paint you might have or not a darker halo of dirt and rust .
And even when you reckognize this details .. using a slightly wrong value or size could make it all more painterly and less photoreal.