Sorry, I was not being very specific with that comment. I don't know much about colouring, lets get that straight. The finished effect you create has a lot of grain, what I meant to say or refer to was considering some 'noise reduction' ? Do you clean up the photo before you colour? ..or does the airbrushing cause the grain. Maybe that is the effect you want ? I have found that the larger the photo the better the results, but not always.