[zzzxtreme]

hi guys, can this be used to adapt pentax super takumar 150mm to pentax 645 body? I see that this K&F adapter doesn't have that pin thing-ey

K&F - no pin


Original Pentax - has pin

[rdenney]

hi guys, can this be used to adapt pentax super takumar 150mm to pentax 645 body? I see that this K&F adapter doesn't have that pin thing-ey

You’ll get a fully manual aperture with stop-down metering. The Pentax adapter will get you an auto aperture, which in that era meant wide-open metering and the camera stops down the lens when you release the shutter.

Rick “who’d rather have the officially correct adapter, despite the cost and the flimsy lock-release button” Denney

[travelswsage]

I think most of the fotodiox adapters are non-pin meaning the lens is completely manual. I have the 67 to k and 67 to eos adapters and both work fine but are completely manual.

[zzzxtreme]

thanks both of you. Much appreciated
Im not sure if I understand the "stop down metering" thing though.

I usually shoot A mode, setting the apeture with the aperture ring. I'm a newbie in film, right now shooting nikon AI lens with F601. That one doesn't have dof preview button.

So I'm still kinda confused. Is stop down metering necessary with A mode with lenses that doesnt have communication with the body?

[travelswsage]

Yes, the metering is stop-down -- even if the lens has an A setting it is not communicated through the adapter. With the camera in manual mode, stop down to the fstop you want to use and then press the green button on the back for proper metering of the scene.

[rdenney]

thanks both of you. Much appreciated

Im not sure if I understand the "stop down metering" thing though.



I usually shoot A mode, setting the apeture with the aperture ring. I'm a newbie in film, right now shooting nikon AI lens with F601. That one doesn't have dof preview button.



So I'm still kinda confused. Is stop down metering necessary with A mode with lenses that doesnt have communication with the body?

Slide the mechanical slide switch on the lens to “M”. Use Av or M on the camera, with the lens set to the aperture you desire. You may not get a meter reading in dark conditions with small apertures—the finder will be dark. Focus before stopping down, or open the lens back up to focus, and then stop it down again before making the photo.

With the Pentax adapter, that lever communicates the lens’s aperture setting to the camera body automatically, and you can meter wide open with the slide switch on A. (There is no A setting on 67 aperture rings, and that setting means something different in any case.) But you still must use Av or M.

The 645z will insist on using Av or M, and will change a Tv or P mode to Av if it can’t control the lens aperture, which it can’t for non-645 lenses (645 lenses have the required A setting on the aperture ring).

Rick “remembering when an auto-aperture was a major new feature” Denney

[unkipunki]

I bought a fotodiox 67 to 645 adapter and sent it back. I'm not sure if this one will have the same issues. What happened for me is that, on the Z, the mirror up function was crippled, so was the 2 second and 12 second timer delay. Also crippled was remote control delay timing. I contacted fotodiox and they replied that the adapter is not supposed to enable mirror up and that live view was the same thing. It isn't and I told them so. They also said that as there is no through signal connections mirror up won't work.

Fellow pentax forum member BobL kindly sent me a Pentax version from France to try and the pentax version had none of these issues. I was relieved to find it wasn't due to my camera body.

[Mercifulfate]

I bought a fotodiox 67 to 645 adapter and sent it back. I'm not sure if this one will have the same issues. What happened for me is that, on the Z, the mirror up function was crippled, so was the 2 second and 12 second timer delay. Also crippled was remote control delay timing. I contacted fotodiox and they replied that the adapter is not supposed to enable mirror up and that live view was the same thing. It isn't and I told them so. They also said that as there is no through signal connections mirror up won't work.

Fellow pentax forum member BobL kindly sent me a Pentax version from France to try and the pentax version had none of these issues. I was relieved to find it wasn't due to my camera body.

Good to know

[Bob L]

.......They also said that as there is no through signal connections mirror up won't work.

As there are no electrical connections from the Pentax adapter either then I'm guessing that the Z has some sensor (micro-switch or prox sensor) that detects the presence of one of the aperture levers when inserted into the body.

Bob

[johnha]

As there are no electrical connections from the Pentax adapter either then I'm guessing that the Z has some sensor (micro-switch or prox sensor) that detects the presence of one of the aperture levers when inserted into the body.

If so, would 6x7 lenses without aperture connections (75mm shift and the tele lenses using the outer bayonet) react differently on the Pentax adapter?

[unkipunki]

As there are no electrical connections from the Pentax adapter either then I'm guessing that the Z has some sensor (micro-switch or prox sensor) that detects the presence of one of the aperture levers when inserted into the body.

Bob

Yes possibly. But my observation is that the pentax version appears to have a 'guard' or 'shorting' plate that covers the connections on the camera mount. The fotodiox had no such thing. It could be something about depressing the contact pins that make it work. Alternatively it could be cross connecting them. What I can't quite understand is that if you take the adapter and lens off the camera and operate it 'nude' all the functions I lost with the fotodiox work flawlessly. That seems to imply some other wizardry at work.

[Bob L]

If so, would 6x7 lenses without aperture connections (75mm shift and the tele lenses using the outer bayonet) react differently on the Pentax adapter?

I've got a 75mm shift so I can give it a try when I get home.