I have a Saunders/LPL which the manufacturer claims to never need adjustment. I am starting to believe it. The enlarger is now in its 3rd building, my wife and I are forever buying a different residence, and I only shoot 35 at this point. I make lots of 20X24 inch prints and they are sharp and crisp from corner to corner and in the middle. I love grain, but it has to be sharp.It is not the answer you were looking for, but it works for me. Don