Front of lens is upside down-- Thoughts?

[AveryMiller]

Hello! Hope everyone is doing well,
I've previously posted about my attempts to fix a "for parts" kowa six, and I've been making a lot of progress. The current issue is with the lens that came with it, a 85mm 2.8. It was disassembled when I received it, with the helicoid separated from the two parts of the lens, without any "witness marks".
I was very concerned I wouldn't get anywhere with this, but after a lot of messing around I was able to reassemble the lens and confirm that the focusing is functioning properly (0.8 meters- infinity)... However, all the markings on the lens are totally off.

As you can see, the front of the lens is upside down, causing the focusing line to be on the underside of the camera. (This rotation isn't an issue with the focus ring, as it can be unscrewed and then readjusted.)

I have no idea how I managed to do this. Below is a normal lens (image from http://kowa.tuberadio.ru/.)

My assumption is that I could simply unscrew the front of the lens, rotate it 180 degrees, and try screwing it back on. But honestly, I'm worried I'm going to mess it up! So if you have any advice or suggestions on how to correct the orientation of the front part of the lens, please let me know!

 

[moto-uno]

I'm going to look into my picture library and see if I have any pics that may help . In the last year I've done 2 or 3 of these lens .
Can't say I've succeeded in getting them off by 180 degrees . Have you any experience in taking lens with shutters in them apart ? It isn't any
where as simple as you mentioned . The focusing ring Is screwed onto one of the focusing helicoils . The top of the lens is screwed
into the inner helicoil and they both have to be correctly started in that central helicoil to get every thing located correctly . If you're
in no rush to take pics , and the focus is correct , then who cares if it takes a few extra moments to set it up . PM me if I can help, Peter

 

[itsdoable]

I have not disassembled the Kowa 85mm, but almost all lenses use 2 guides to keep the base and optics in sync between the helical threads, you most likely just have to flip them around by 180 deg. Of course that means you have to find the thread start that matches that. If the shutter still tensions, then you are probably fine to taking pictures. Some lenses use a single arm for tensioning, and those will not work when you have the optics off by 180deg.

 

[AveryMiller]

Have you any experience in taking lens with shutters in them apart ? It isn't any
where as simple as you mentioned .

Mr. Peter-- I appreciate your diligence, you really are a kowa maestro! I'm still having problems with private messaging, as I believe I haven't made enough posts to unlock the feature, but when I do I'll be sure to reach out (I'm sure some photos might be helpful!) I have very little lens repair experience, and hearing that the focus ring can't just be readjusted to aligned makes this even weirder. Because the focus ring was mounted to the helicoid when I received it, I was able to mark it's original location, and that's where it is now! I must have made some kind of mistake when marking the ring and the helicoid, as I don't know how else I could have got these results. You're right, I shouldn't be too concerned about this as long as it works!

you most likely just have to flip them around by 180 deg. Of course that means you have to find the thread start that matches that.

I think this is what I'm going to try! I have to apply new grease to the helicoid, so I'll give it a try then.

 

[moto-uno]

^ I've gone through literally thousands of my photos and it appears that pictures of the helicoils starting locations were in fact in my imagination . Peter
you can contact me at "marvelousmr@hotmail.com" if you have some photos I can check out and see if there's anything obviously needing change .

 

[wiltw]

Optically it likely does not matter. Operationally it is a pain the arse to have to flip it all upside down to set aperture to the desired setting.

I recently purchased an old T-mount lens, and when I first mounted the T-mount adapter and put the lens on the camera, it was upside down. Fortunately it was simple to loosen three screws on the T-mount adapter and rotate the entire lens within the mount. But such is not possible when the lens employs mechanical linkages, via pins or leverls, to interface to the body. Manual control lenses and preset lenses are fine, but any automation defeats simple rotation

 

[BradS]

I don't know anything about this particular lens but, I wonder if it could be put right by simply re-orienting the mount. Is it possible that the mount is 180 out? If this were the case then the lens would all be right but the mount would just need to be flipped or rotated or whatever...but maybe it is designed such that this is not even possible?IDK.