Framelines & modifying adapters

[rxmd]

Hi,

I have a spare M adapter for 50/75, and I need one for 28/90. Is it possible to modify the adapter by filing down the appropriate lug in the 2 o'clock corner?

Philipp

 

[ocean7]

I guess it is possible. I modified a Rokkor 40/2 to bring the 35mm framelines on my M6. That's quite easy and you don't need to file much. I removed maybe 1mm of metal. Just go a little bit at a time and mount the lens to see the result as you progress.

 

[rxmd]

If I look at the way the frameline lever works in my M5, it looks like the frameline positions on the 2 o'clock lug are as follows:

- top: 35/135 (short lug)
- center: 50/75 (medium-length lug)
- bottom: 28/90 (long lug)

That would mean that it is easy to modify a lens or adapter to bring up 35mm simply by filing down (or to modify a 28mm lens to bring up 50mm for whatever reason), but difficult to modify things in the opposite direction because one would have "build up" the frameline lug. Am I basically correct in this assessment?

Philipp

 

[pvdhaar]

Hi,

I have a spare M adapter for 50/75, and I need one for 28/90. Is it possible to modify the adapter by filing down the appropriate lug in the 2 o'clock corner?

Philipp

No, it's the other way round..

You can turn a 28/90 into a 50/75
You can turn a 50/75 into a 35/135