Mamiya 7 Rangefinder Adjustment
The following procedure assumes that your Mamiya 7 was at one time in good, known focus. This is NOT a re-columniation, though Iíll cover that under another procedure.
If youíve ever browsed for Mamiya 7 things on e-B$y youíve probably noticed folks selling a rangefinder adjustment kit for as much as $50.
Thatís a bit much.
I went to Lisbon last year and noticed that after I stuck the 150mm lens on the camera, the rangefinder was off in both vertical and the horizontal. It wasnít much, but it was noticeable and with the 150mm being notoriously difficult to focus wide open, I wanted the camera right.
I went to the Columbo mall and then to Aki to buy a set of jewelers screwdrivers (6 Euros)Ö
Be aware that Mamiya themselves have posted a procedure on their user forum site, but itís hard to find, and I didnít, at the time, have the benefit of looking for it, deciding to handle the matter in hand, so to speak. Having read it after the fact, there is a warning I want to include:
Do NOT turn the vertical adjuster more than ľ turn in either direction, or damage to the camera may result.
***End of warning***
Be aware too, of course, that these repairs are on you. Neither I nor this site take any responsibility for damage to you or your camera. Basically, if you break your camera in half, you get to keep both halves.
Here we go:
Pop the little plastic cap off the back of the camera. Itís soft-ish plastic, so do it gently. Everyone in the world will know that you adjusted the rangefinder anyway, but take some care to pull the plug out in such a way as to minimize any damage or impressionsóitíll fit better later.
Look inside the hole that the plug covered. Youíll see two screws. Those are the rangefinder adjustment screws. The upper (and more recessed one) is the vertical alignment, the raised one is the horizontal adjustment.
Making sure that there is no gunk on the rangefinder coupling (either the lens or the camera side!), mount the 80mm and turn it to infinity. Find a spot with a cell tower (common in Europe) or radio/TV antenna a mile away (1 km worked fine for me) in view.
Look through the viewfinder and see where the images align. This rangefinder has a TOUCH of dependencies between the vertical and horizontal adjustments, but itís not as bad as some Iíve adjusted. Go for the vertical first.
Put the right sized screwdriver (use one that really fits the slot!) into the upper and more recessed screw and turn just a bit- 1/16th turn is probably too much. Look through the viewfinder and see how much youíve done. If too much (likely, of you werenít too far out of adjustment with which to begin) back it off slightly, or go for a tad more. Adjustments here are slow. Take your time, and get it right. Complete it and make SURE that the adjustment is as close to perfect as you can.
Working on the horizontal, first double check that the lens is at infinity. The screw to adjust is the raised one. Same thing as the vertical adjustment, do only small motions with the screw and make it perfect. You might at this time have to re-adjust the vertical adjustment if you had to do more than a Ĺ turn on the horizontal. Get it RIGHT. Once you are done, crank the lens to close focus, then back out to infinity, just to check. I hit the camera against the palm of my hand to jar things, but I understand wanting to forego that step. Check vertical and horizontal again, and re-run the procedure if necessary.
Once you are done, and itís PERFECT, try your other lenses and just make sure that none of them are not set for infinity correctly. My 150mm was EXACTLY the same as the 80mm when it came to infinity focus, contrary to what Mamiya has said about the 150mm focusing slightly past infinity.
The final step, should you choose to do it, is to put a drop of locktite (thread locking compound- THE WEAKEST) on the horizontal (raised screw) adjuster. I didnít do it, and for the remainder of my trip, my rangefinder was just fine- it never crept out adjustment again.
Itís an easy fix that took 15 minutes in the field. I saved several dollars from going to someone whoíd send me an instruction manual and screwdriver for $50, and it didnít have to go back to Mamiya. Better yet was my feeling of certainty when using the 150mm lens on the camera.
Good luck & light!