So I'm not the only one with that problem. My problem is that I can't retouch on the computer very well. I sketched a profile of my wife in 1964 while she was watching TV. Recently I scanned it in but it is so badly smudged from being in an album for 40 plus years that I haven't been able to clean it up.
They do take a lot of time and patience to retouch - at least mine did, because in the results of the scanned sketches, the pencil shading and lines weren’t consistent - some were dark and splotchy and not nearly as smoothly blended as the original. Here’s another odd thing: I am left-handed and cannot draw nor even write my name where you can read it with my right hand - yet, I have never been able to use my mouse with my LEFT hand, thus I do every bit of detail with my right hand. :)