Repair work dilemma....

[ed_yuen]

Hello everyone:

 

I'm facing a bit of a dilemma for some repair work. I acquired a Pentax SMC-A

100mm Dental Macro lens a while back. The glass is great, but it appears that

some previous owner 'modified' it to fit another camera (possibly a Canon).

Both the lever that the 'A' setting uses to set the aperture and the guard along

side of it were cut off. Now, after some hands on research and observations I

feel that I can replace the the guard piece by sacrificing one of three macro

rings (also Pentax) for the required part. The lever I've gotten from a lens

that suffered some sort of water damage.

 

Now the real question; which ring should I use (or sacrifice)? Given that once

the part is removed the lever will most likely still work but will not have the

protection of the guard, and any chance of selling it drops off considerably.

Which of the three rings would most people use the least often? The most?

 

I already have two other complete Auto Extension Tube sets but am trying to

minimize the 'damage' to the remaining set in the hopes of maybe selling it

later. Regardless, any suggestions would be appreciated. Thanks.

[personalphotos]

Can't you take the guard off the damaged lens? I've done that with one of the older Vivitar's that had a guard that was too large. Took the guard off another lens that had issues and in a few minutes had a perfect Vivitar, ready to go.

[ed_yuen]

Removing the guard isn't a problem, I want to replace it with an intact one. I had the guard from another lens which I got the lever from but it's significantly different from the macro lens one rendering it unusable. The guard on the macro ring is essentially the same as the macro lens.

 

I could theoretically use the lens without the guard but I prefer to have it as a precaution.

[personalphotos]

Well that's your call but the guard is not a big deal unless you are not very careful with the lens. The old M42's had small aperture pins sticking out from the back that were not nearly as strong and unguarded. Just seems like a waste to ruin a set of extension tube when you don't really have to unless you plan to sell the lens.

 

If you plan to sacrifice one of the rings then take the smallest one. But most people wold want the set intact. Then again they don't sell for high prices anyway.