yep, and it is rare that you would need to make more than a few adjustments. However, I have seen some very complicated printing maps. I.E. Richard Avedon's prints look lilke a topological map.

You might try to find a book by Larry Bartlett called "Black and White Photographic Printing Workshop". He was at one time considered a master printer (he is no longer alive), but the book is very good with examples, etc.

Of , course there are others out there with books that can be helpful, google Tim Rudman, Les McLean, for a few as there are others who have written helpful booiks.