As I mentioned in another post under Silents, I'm working with 8x10 negatives at this point. Scanners with a light unit in the cover are great for processing color or b/w negatives but typically they are only 2.5 inches wide, although the length is fine. These dimensions work for smaller negatives but are very restricting for 8x10s. To work around this, I scan the neg in three or four sections then line up the pieces into a hopefully seamless portrait. I'm bedeviled by two problems - the first is matching up hands and fingers with shoulders and arms. You'd think that matching one area would take care of the other but it doesn't always work out that way. The second problem is differing contrasts for different sections. Even where the join is seamless, the contrast level say on a back wall will differ making it look like it was pieced together.
I found a partial solution in the Photoshop photo fix feature. Here are some examples. First the individual sections:



Here is a basic assembly, You see the different textures over the window and the problem I had matching the arm and vest with the hand and fingers. I could match one or the other but not both:

A combination of colorizing, uh, painting, and photo fix helps smooth out some glaring problems but not all. Can we start a rumor that Wally Reid only had three fingers on his right hand?

Wallace Reid in FOREVER (1921)