mamya tlr 135mm spacer issue

[che]

hi, I took the elements out for a cleaning. they simply turn out the front. after glass is removed, there is an '8' shaped spacer ring that sits on the barrels. I just noticed that the '8' shaped spacer ring is not symmetrical. One 'o' of the ring is thicker than the other and I'm not sure if the thicker 'o' goes under the viewing or taking lens. It seems that whichever way it goes, one of the lenses will protrude a tiny bit farther forward. Thanks for any help

 

[Sirius Glass]

Welcome to APUG

I sold my Mamiya years ago, so I cannot help but others here can.

 

[macfred]

This one is about the 65 mm f/3.5 disassembling - maybe it will help ... ? http://www.flickr.com/photos/soundsk/sets/72157631644580668/

 

[Kirks518]

Congratulations! You have succeeded in removing the focus calibration ring.

Now, to put it back correctly, you'll need to do a quick focus calibration. Put the ring back on, put on the elements, and find a good target. Focus on the target using the ground glass, and check the focus on the film plane to see if it too is in focus. To check focus on the film plane, I grab a ground glass, and secure it (aka tape it) at to the rails for the film. Fun times.

If it isn't in focus, flip the ring vertically, and try again.

You have a 50/50 chance of getting it right the first time.

 

[che]

Thanks kirks518, the ground glass on the frame rails is a great idea. I had come across that calibration method a while back and totally forgot.

 

[film_man]

Worst case if you can't sort it out shoot a roll and if it comes out fuzzy then you know you got it wrong!

 

[Christiaan Phleger]

and make sure the foam on the focussing screen frame isn't stuck and affecting the position of the screen. Any non factory spacer ring is suspect, usually to correct for an offset in the focus as I just described.

 

[Kirks518]

and make sure the foam on the focussing screen frame isn't stuck and affecting the position of the screen. Any non factory spacer ring is suspect, usually to correct for an offset in the focus as I just described.

True, but that would only be an issue if there was a focus issue previously. If all the lens (and any others the OP may have) was focusing fine, then most likely the foam is fine.

 

[Christiaan Phleger]

If the camera is set up correctly no shims are usually needed or if needed quite thin. From the OP i think its not original factory so thats a sign to look to correct a deeper issue. With this system focussing errors are less noticeable with certain lenses. Get the screen right and each set of lenses will be good throughout the focussing range.