[stevebrot]

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I learned something this evening that really surprised me. As many of you know, the SMC and S-M-C Takumar lenses have a small pin on the mount face that provides an interlock for the aperture mechanism open-aperture metering. Many of you also know that the mount flange on Pentax M42 bodies is smooth with no screw holes. This is not the case with all M42 bodies. Many other brands attach the flange to the body with counter-sunk screws through holes drilled through the face. These other brands include Ricoh, Mamiya/Sekor DTL models, Zenit and who knows what others.

Have you guess the problem yet? That very tiny SMC pin has the potential to act like the infamous "Ricoh Pin" when mounted to a susceptible camera. Screw the lens on and the pin retracts until it comes to the edge of the counter-sunk screw hole. Try to remove the lens and...oh, oh!

No, my S-M-C 28/3.5 is not stuck to the Singlex TLS and for that I am thankful. From the look of things, the problem is only present for those bodies whose threads are cut such that the pin "lands" at the very edge of a screw hole. I don't know if it provides a degree of insurance, but I was wondering if there is any sense in taking care to retract the pin (move A/M switch to the M setting) before removing the lens from the camera. This might be a reasonable precaution for those of us having a mix of M42 lenses and cameras. Even then, there looks to be some protrusion.


Steve

[wirrah]

The same problem exists for some Pentax equipment. Don't try mounting an SMC on an early Asahi bellows. Been there once before...

[stevebrot]

The same problem exists for some Pentax equipment. Don't try mounting an SMC on an early Asahi bellows. Been there once before...

I was having a few regrets about posting this notice. After all, mounting a SMC lens to a non-Pentax camera is a "one-in-a-million" case. Now I know that the call for caution is quite valid and might extend to various accessories such as bellows, extension tubes and lens/body adapters having indentation or cutouts in the mount face. At the very least, there is risk of damage to the lens mechanism.


Steve

[vintageslrs]

Yep...do not mount those lenses on any Fujica ST801 or an ST901 or an ST705.
If you do, you will have a very difficult time removing it.

Bob

[stevebrot]

Yep...do not mount those lenses on any Fujica ST801 or an ST901 or an ST705.
If you do, you will have a very difficult time removing it.

Bob

Welcome to the Pentax forums and thank you for adding your comment to this thread.


Steve

[vintageslrs]

Thank you Steve.

[titrisol]

I haven't had problems with the Fujicas... so far

[vintageslrs]

Really, I am surprised....that pin can get caught in one of those tiny screw recesses and jam the lens on.....
happened to me years ago. Was a real b----- to get the lens to come off. I did eventually get it off without any damage.

Which Fujica's have you used the lenses on? I know the ST701 does not have those screws......not sure about the ST605?
But the ST801,901 and 705 for sure do.

Bob

[vintageslrs]

I just checked a ST605N and they do not have the screw recesses so the SMC Takumar lenses will be OK on that Fujica.

[BarneyL]

Sorry for resurrecting a super old thread, but I'd like to add some insight, due to my latest acquisition - Fujica ST705W (the 'w' is important here)


This camera, like the ST605N, does not have screw recesses and SMC Takumars mount without issue (and focus to infinity); I believe it applies to all cameras of that model, but it's always good to check how the mount looks like before buying, because I have seen Fujica AZ-1 in two versions, with and without screw recesses on the mount. I assume the AZ-1 version without these screws should work with Takumars as well.

So, if you'd like an SMC Takumar-compatible M42 camera with fast SPD meter, max shutter speed faster than 1/1000 (1/1500 in this case) and a winder option, ST705W is worth considering.

[Yossarian22]

BarneyL

can you tell me how super takumar lenses meter on the st705w ?
is it manual mode stop-down on the lenst
(dark viewfinder)
or maybe its more like Spotmatic F ?

[BarneyL]

My Fujica meters in stop down mode with Takumar lenses. Only Spotmatic F and ES models work with open aperture metering features present on S-M-C and SMC Takumar lenses.


By the way, it looks like contrary to what I posted earlier, quite a lot of ST705W models have the older-style mount with screw recesses, so one has to be cautious before trying SMC Takumars on it, just like with AZ-1.

[Yossarian22]

Can you direct me to a picture of what "older style mount with screw recesses" looks like ?

[BarneyL]

Old style
Fujica ST705W Body Analog SLR Camera Camera Body SLR | eBay

New style
Fujifilm Fujica AZ-1 35mm Film M42 Screw Mount SLR Camera. RARE Black model | eBay

[Yossarian22]

Thanks BarneyL for the links. So the four recessed screws might grab and keep the tiny pin (not the aperture pin) on lenses that have it?