A strip of masking tape on the focus ring told me more than my $200 alignment rig
Had a customer's 50mm lens come in with focus that drifted past infinity, and after two teardowns I was still guessing which way the element needed to go. Out of frustration I taped a thin strip across the focus ring, marked the sharpest point with a pencil, and kept nudging until the mark lined up with the infinity stop. Took me 20 minutes instead of the usual hour, but I'm wondering if anyone else has a low tech way to dial in focus without dragging out the collimator every time.
Honestly the "taped a thin strip across the focus ring and marked the sharpest point" thing is so real, I've done almost the same with a piece of painter's tape and a fine Sharpie. There's something about seeing the mark move in real time that just clicks in your brain better than staring at a collimator readout. Two teardowns and still guessing is the worst feeling too, been there and it makes you want to throw the thing across the shop. Sometimes the cheap trick just works because you're getting feedback right where the problem actually is. Thanks for sharing this, I'm going to keep a roll of tape on the bench from now on.