[nathanduncanphoto]

So I have a "common" P645 and I just ordered an additional one as a back-up from a shop in Japan via eBay. (I ordered my other one in the same manner) Anyway, the one that I've been using is likely common to yours as the dial wheel on the left rear is for SINGLE or CONTINUOUS shooting. The new one is like the old one as they are both original generation models, but the new one has a different dial wheel. Instead of C/S, it's a half stop exposure adjustment. ALSO the guard wall surrounding the ON/OFF switch on the handle is beveled like a ramp instead of simply raised above the ON/OFF switch. Anyone ever see this version before? Or have info on it? The serial number on this one I just bought is a little older than my other one (which I estimate to be an early 90s production era). You can see these two serial numbers that I've entered in the serial numbers section of this webpage. Questions, comments, or answers welcomed. Thanks!

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[IgorZ]

I have one like that. When I asked the same question you did one of the members here told me that it was a factory modification for shooting slide film. He said that he had only ever seen 2 of these and mine was the third. Since then another forum member got the same model. I haven't looked into it more, so that's all I know.

[Jonathan Mac]

I remember reading somewhere that this could be done as an option. I think it would be pretty useful, though you can roughly simulate it by changing the aperture by a half stop (since the shutter speed is in full stops). My 645 is the standard version.

[seventhdr]

So what does the +- EF button do on your version now that exposure compensation is on this wheel?

It's the top of the three buttons on the left.

Regards

Chris

[nathanduncanphoto]

So what does the +- EF button do on your version now that exposure compensation is on this wheel?

It's the top of the three buttons on the left.

Regards

Chris

Hi Chris,
The +/- EF button still operates as normal, but can be used along with this wheel for a finer level of adjustment. The button does whole stops and then I can spin the wheel + or - for additional 1/2 stops. OR: I can just use only the wheel for 1/2 stops whilst leaving the button at 0 EF.

[seventhdr]

Okay. Thanks for that update.

Regards

Chris

[Hugo Bucussi]

Hello,

Sorry for bringing this one back to life after almost 6 years. But I didn't want to create another topic on this subject.

I've been shooting with my K-5 for quite some time now, but after watching many videos about film photography, I'm inclined to give it a try. I love my K-5 and the lenses I have, so I was looking to purchase a Pentax 645. I saw a couple of them with this manufacturer mod and was thinking if this is really a bonus and worth paying the extra +/-£30 for it. I definitely won't be using the CONTINUOUS shooting option that the original ones have, so it might be worth the extra +- EF function.

[Jonathan Mac]

If I could have had that option at only £30 more then I would have. Bear in mind that the shutter speeds on the 645 change in whole stops only so unless you change your aperture the meter might not be giving you a very accurate reading, even if the meter itself is accurate, because as it's reflected in shutter speed changes is not very accurate.

[Random49]

If I could have had that option at only £30 more then I would have. Bear in mind that the shutter speeds on the 645 change in whole stops only so unless you change your aperture the meter might not be giving you a very accurate reading, even if the meter itself is accurate, because as it's reflected in shutter speed changes is not very accurate.

Does this mean that the modified version includes half stop shutter speeds as well? Otherwise, I'm not sure how much difference +/- half stop compensation would make when relying on the camera's meter, not unless it changes how the camera decides to round the shutter speed up or down. In any case I would assume the camera errs on slight overexposure versus underexposure.

Could you not easily accomplish the same thing by setting the ISO half a stop lower (rate 200 at 160, 400 at 300, etc.)?

---------- Post added 12-13-23 at 06:39 PM ----------

Hello,

Sorry for bringing this one back to life after almost 6 years. But I didn't want to create another topic on this subject.

I've been shooting with my K-5 for quite some time now, but after watching many videos about film photography, I'm inclined to give it a try. I love my K-5 and the lenses I have, so I was looking to purchase a Pentax 645. I saw a couple of them with this manufacturer mod and was thinking if this is really a bonus and worth paying the extra +/-£30 for it. I definitely won't be using the CONTINUOUS shooting option that the original ones have, so it might be worth the extra +- EF function.

I think you could accomplish the same thing by changing the ISO (very easy to do on the 645), it has a huge range of ISO settings. As for film in general, in some ways it's very different from digital. For example, there is a tendency to rate exposure for highlights and not shadows because it's difficult to recover highlights with digital. The opposite is true for film.

If your budget allows, I would recommend also buying an inexpensive 35mm SLR with a short/mid prime lens (say 35mm or 50mm) so that it will be more affordable to learn. 120 and 35mm are roughly the same price, but you'll only get 15 exposures from the 645 whereas 35mm is 36 exposures. There are some really great manual SLRs available for very little money. A while back I bought a Minolta XG9 for $30 on eBay and it included a 50mm lens. I'm currently still using that camera regularly.

[Jonathan Mac]

Does this mean that the modified version includes half stop shutter speeds as well? Otherwise, I'm not sure how much difference +/- half stop compensation would make when relying on the camera's meter, not unless it changes how the camera decides to round the shutter speed up or down. In any case I would assume the camera errs on slight overexposure versus underexposure.

Could you not easily accomplish the same thing by setting the ISO half a stop lower (rate 200 at 160, 400 at 300, etc.)?[COLOR="Silver"]

It would allow you to easily move the exposure comp up and down half a stop to see how the meter responded and get an idea of whether your exposure is erring up or down. The only way to modify the actual exposure by less than a stop is to use the aperture ring with the camera in M or Av modes.

[Hugo Bucussi]

Thanks everyone for the answers. I've found that if I buy the camera from Japan, I might be able to get a 645N, which I think might be helpful for me as a learning curve.

The problem with Japan purchases is that they have such an amazing variety of cameras available, I started looking for Pentax 645 and suddenly found the P67, Mamiya RZ67 and they look like really such great cameras, but to have 9-10 exposures is a little bit harsh on my wallet for beginning.

At the moment I'm watching a 645N kit with a FA 200mm lens, but I think it might be too long for what I normally shoot, so I'm also looking for the 80-160mm lens. How you normally convert the lens into a "full frame" factor? On my K-5 I constantly use my Pentax 16-50, 95% of the time between 35-50mm. But I also have a Pentax 100mm that I really like to use outside.

[marco_gea]

It would allow you to easily move the exposure comp up and down half a stop to see how the meter responded and get an idea of whether your exposure is erring up or down. The only way to modify the actual exposure by less than a stop is to use the aperture ring with the camera in M or Av modes.

Setting the aperture ring in half stops to change exposure works in M mode yes, but not in Av mode.

The exposure time in Av (and P) varies continuously, not by discrete full stops (even though it is only shown to the nearest full stop in the viewfinder).

Hence, the 0.5 stop exp comp dial is the way to go in Av, P or Tv modes.