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02-19-2021, 04:13 PM   #16
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QuoteOriginally posted by JJ-eire Quote
I see nothing on the Laowa mount that could obstruct mounting
Based on the comment above by JensE, it is what is not there that may be the cause of the problem.


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02-19-2021, 04:15 PM - 1 Like   #17
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QuoteOriginally posted by stevebrot Quote
Based on the comment above by JensE, it is what is not there that may be the cause of the problem.
Well, there is too much solid metal where the should be none
02-19-2021, 04:20 PM   #18
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QuoteOriginally posted by JensE Quote
Do you think it makes sense to contact Laowa and IRIX to point out the potential damage on classic cameras?
It would make sense indeed.


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02-19-2021, 04:26 PM   #19
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QuoteOriginally posted by Lowell Goudge Quote
Can you send pictures. I agree I like to consider all my stuff as a system. 3 film bodies, 5 digital bodies (crop and Ff) and 60 lenses
60 lenses? That's a fair amount, well they always say invest in glass. I have a good selection of film cameras and lenses, nothing fancy though. The only Leica I have is a broken M4P. I assumed Pentax lenses offered the same compatibility as Nikon, I can use VR/SR and AF on my F80 and nearly all the lenses mount on all the F-mount cameras with few exceptions. Old lenses on new cameras and new lenses on old cameras.

Here is a link to the camera mounts and the Laowa lens mount.


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---------- Post added 02-19-21 at 04:39 PM ----------

QuoteOriginally posted by JensE Quote
Just carefully checked the Laowa 100mm on a Program A: It is the coupler, for which there is no space in the lens mount. The Laowa would meter correctly in the A-Setting on cameras that support it. Do you think it makes sense to contact Laowa and IRIX to point out the potential damage on classic cameras?
The thing is that Pentax shooters are probably in the minority concerning their customer base and Pentax film shooters who use Laowa and Irix are more than likely few and far between so getting them to modify their future mounts may be a tall order. But yes they should be informed.

Having read what you said I checked the mounts of the MZ6 and 30. I believe the aperture coupler reduces the amount of room for the lens to rotate and that's why it can't mount (but it will mount if forced as I did on the KM, no damage as far as I can see, the lens aperture still stops down as it should on other lenses)

02-19-2021, 04:43 PM   #20
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It almost looks like the lens is hitting the prism housing just at the center. Look closely at the depth of protrusion of the lens from the mount, the diameter of the protrusion, and the depth of the prism housing on the KM
02-19-2021, 04:54 PM   #21
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I added some photos to onedrive with the lens mounted on the KM, it doesn't touch the prism housing. After the first time that I forced it on the KM, it mounts with some resistance and it can be tricky to dismount but it's still useable and doesn't seem to have damaged the camera mount.
02-19-2021, 04:58 PM   #22
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QuoteOriginally posted by JJ-eire Quote
Having read what you said I checked the mounts of the MZ6 and 30. I believe the aperture coupler reduces the amount of room for the lens to rotate and that's why it can't mount (but it will mount if forced as I did on the KM, no damage as far as I can see, the lens aperture still stops down as it should on other lenses)
The damage would not effect stopping down the aperture. The coupler transfers the aperture ring rotation to the camera (proportional to number of stops from fully open), so that the camera can determine correct exposure times even though measurement is taken at open aperture. So if anything, metering is impacted.

02-19-2021, 05:09 PM   #23
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QuoteOriginally posted by JJ-eire Quote
Here is a link to the camera mounts and the Laowa lens mount.
Thanks! Strangely, there is a (unneeded) carved out trough to avoid the mount contacts, but no provision to miss the coupler.


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02-19-2021, 05:12 PM   #24
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QuoteOriginally posted by JensE Quote
The damage would not effect stopping down the aperture. The coupler transfers the aperture ring rotation to the camera (proportional to number of stops from fully open), so that the camera can determine correct exposure times even though measurement is taken at open aperture. So if anything, metering is impacted.
Ok, I think I get what you mean now, the coupler sticks out a bit too much and might be stopping it from mounting and when I mount it then it is forcing it in. I shot a roll on the KM + 15mm but I used an external meter, since ultra wide angles are tricky to meter anyway.

So would filing it down a bit negatively affect its function and would it solve the problem? Basically my end goal is to mount the lens on the cameras, metering is not necessary.

---------- Post added 02-19-21 at 05:16 PM ----------

QuoteOriginally posted by stevebrot Quote
Thanks! Strangely, there is a (unneeded) carved out trough to avoid the mount contacts, but no provision to miss the coupler.


Steve
I'm guessing they just tested it on DSLRs and called it a day. I doubt they considered film users ( a pity because it has an aperture ring)
02-19-2021, 05:24 PM   #25
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QuoteOriginally posted by JJ-eire Quote
So would filing it down a bit negatively affect its function and would it solve the problem? Basically my end goal is to mount the lens on the cameras, metering is not necessary.
I would not recommend that - hard to avoid metal dust in the camera mechanics and you will lose the ability to meter with pre-KA lenses (K and M lenses) or A-lenses in non-A setting. I'd rather take the lens mount off and modify that - but that depends on what tools you have available.

QuoteOriginally posted by JJ-eire Quote
I'm guessing they just tested it on DSLRs and called it a day. I doubt they considered film users ( a pity because it has an aperture ring)
Thinking about it, I think the Laowa actually had some warning about potential damage in the package, which I discarded - it didn't explain the nature of the problem.
02-19-2021, 05:31 PM   #26
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QuoteOriginally posted by JensE Quote
I would not recommend that - hard to avoid metal dust in the camera mechanics and you will lose the ability to meter with pre-KA lenses (K and M lenses) or A-lenses in non-A setting. I'd rather take the lens mount off and modify that - but that depends on what tools you have available.


Thinking about it, I think the Laowa actually had some warning about potential damage in the package, which I discarded - it didn't explain the nature of the problem.
I read in different lens reviews that some 3rd party lenses are not compatible but they didn't explain why exactly. It looks like you can take off the mount easily. I just have some screwdrivers and some sandpaper. Not enough for a decent modification
02-19-2021, 10:19 PM   #27
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QuoteOriginally posted by JJ-eire Quote
(I was like a K-mount is a K-mount, therefore it should fit on and it did, with considerable effort)
Well, not really. I have a Vivitar 2 Macro Teleconverter made in the 1980's and my genuine Pentax M42 adapters will not fit in it. Third party lenses can have subtle (or not so subtle) differences that adds up to incompatibility. Look at the old 3rd party lenses with the overly large shield for the aperture lever. Perfectly fine on bodies without zoom contacts but require modification on bodies with zoom contacts.

Forcing photo equipment to fit is never a good idea. I bought a "Polaroid" branded T2-mount adapter (made in India) that would not thread on to the adapter that came with my mirror lens. Forcing it on may have stripped the threads on the telescope adapter. T-mount should be T-mount but not in this case. The adapter went back for refund and I found a new-old-stack K-mount version from the same brand as my Minolta T2 adapter (made in Japan).
03-08-2021, 04:28 PM   #28
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So I just got my Irix 11mm back from being repaired (dodgy aperture lever), I tried it on an MZ-S, it mounted with a bit of persuasion and works in P mode.

I usually don't force mount lenses but it's a K-mount and I didn't buy it to just use it on an MZ30.
03-08-2021, 08:02 PM   #29
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QuoteOriginally posted by JJ-eire Quote
I usually don't force mount lenses but it's a K-mount and I didn't buy it to just use it on an MZ30.
The gear is yours to do with as you please.

Remember to mention the lenses if you need future repair help with your MZ-S. It will give the tech person a starting place.


Steve
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