[Denverdad]

I just purchased my very first medium format camera off of ebay - an Asahi Pentax 6x7 with MLU, TTL prism and 105/2.4 lens. Unfortunately it appears to have some "issues" .

The main problem is that the shutter and mirror have a tendency to get stuck open. It sounds very much like the problem in this recent thread (except the solution there didn't seem to help): https://www.pentaxforums.com/forums/pentax-medium-format-645-6x7-645d/54491-6...tuck-open.html

Here are the symptoms: First of all the shutter and mirror do function properly sometimes - typically for several actuations, then the mirror/shutter lock up. For what its worth, it tends to be less of a problem at fast shutter speeds - in fact it seems I can shoot indefinitely at 1/1000s without problems, but at say, 1/2s I am lucky to be able to shoot once or twice before the problem manifests itself.

When I depress the little mirror release button on the front it doesn't help (stays stuck). Once stuck, the only thing which releases it is to remove the battery. And sometimes even then, the camera needs a gentle rap to encourage it to release.

The battery is a brand new Duracell P28L Lithium. Per the above thread, I cleaned the battery compartment contacts, but they were very clean to begin with and it didn't have an effect.

So I'm beginning to think that the camera is going to need some service, but would be interested to hear of any suggestions before I send it in.

Thanks,

Jeff

[mk07138]

Hi Jeff,

I'm the guy who just had this problem with his 6x7. If you've already tried the whole battery thing then I'm not quite sure what would be the exact cause of the trouble you're having. My vote is that it's still power related and maybe there is a problem somewhere further up the circuitry. I would definitely recommend sending it in for repairs regardless just so that you know it's in pristine shape when you start using it. You don't want to run a few rolls of film through, get them processed and realize there is something really wrong with the camera. Mine was working pretty well but I sent it away to get cleaned up and adjusted here: Home

He is highly recommended on this site and has been very courteous. I'm still waiting to get my camera back from him, but it hasn't been that long yet.

Hopefully you figure it out. I know that the first few rolls that I ran through mine the camera felt great and is a lot of fun to use.

Morgan

[monochrome]

Hi Jeff,

I'm the guy who just had this problem with his 6x7. If you've already tried the whole battery thing then I'm not quite sure what would be the exact cause of the trouble you're having. My vote is that it's still power related and maybe there is a problem somewhere further up the circuitry. I would definitely recommend sending it in for repairs regardless just so that you know it's in pristine shape when you start using it. You don't want to run a few rolls of film through, get them processed and realize there is something really wrong with the camera. Mine was working pretty well but I sent it away to get cleaned up and adjusted here: Home

He is highly recommended on this site and has been very courteous. I'm still waiting to get my camera back from him, but it hasn't been that long yet.

Hopefully you figure it out. I know that the first few rolls that I ran through mine the camera felt great and is a lot of fun to use.

Morgan

For a bit more about Pentax Camera Service and Eric Hendrickson (he has a K2 DMD of mine right now for a CLA), go to Forum >> Off-Topic Forums >> External Links >> Camera Repair and Service. You can also get there from Home >> Links >>

[desertscape]

If you have just purchased your Asahi 6x7 and it has problems, I would contact the seller and say that you were sold damaged goods. There should be some sort of compensation. The problem you describe is quite common as this camera ages. After 10,000 frames or so, the mirror becomes inconsistant and locks up like you describe. I sent mine to Pentax Colorado with this problem 2 yrs ago but they may not be repairing the 6x7 now. Buying the Asahi used can be problematic. Suggest getting the mint cond ones. Even then, the TTL meters can be way off being that old.

[Denverdad]

Thanks for the replies. Here's my last "grasping at straws" attempt to solve the battery question: Is there any chance that the type of battery matters? The manual calls for a silver-oxide battery (which I know isn't made anymore), and I am using a Duracell lithium battery. What are you using, and does it matter?

Aside from that issue, I mentioned there were other problems. For one, although the meter "works" (in the sense that the needle moves) it is very inconsistent and the position can be changed by jiggling the camera about. Basically it is useless.

Also the prism doesn't seem to sit very securely on the camera - there is more play than what I would have expected. This may be due to bad seals (I assume there should be some, but its mostly just a sticky layer of gum left where the prism sits on its frame). I notice that the back has more "play" in it too, so it wouldn't surprise me if it needs new seals all around.

The last thing is something which seems really odd - the exposure counter dial appears to be on backwards (see the picture below)! It is clocked 180 degrees from what the manual shows and what I see in pictures online. So unless this is just some rare version of the camera I don't know about, I might think it is the result of a poor servicing attempt. I have not run any film through the camera yet to know if it affects proper film advance or frame counting or anything along those lines.

Finally I agree with you desertscape, I should try to return it. Unfortunately given the statements in the auction about "no returns" and "all sales are final", I don't think he will go for it. But the camera is hardly "fully functional" as stated.

Jeff

[desertscape]

I have used the lithium batteries before with no problems but prefer the Panasonic silver oxide. They are still made, last I checked. Two of my bodies have silver oxide and one has lithium.

The meter needle will bounce a bit but it should not move a lot, as you have described.

The prism will rock a bit on top of the body but when the foam is shot, it will really move. You may be able to get by with it the way it is, unless the foam is falling apart.

Your exposure counter window was put on upside down. The window should be on the top part of the circle. It should work but it is inconvenient.

[mk07138]

I'm using a duracell lithium battery in mine and it's working well now. By the sounds of things you definitely need some new seals on the prism and back. When I got mine it was the same as what you're describing with nothing but sticky gum left. I don't know what you paid for yours, but from the sound of things if you paid over $400 for it I might get a little peaved. I paid just over $400 for mine and after servicing from Eric I cost me all told just under $600 for the body and lens, and now it looks brand new. I haven't had a chance to run any film through it since getting it back but it's loaded with a roll of Reala and I have 2 rolls of Velvia and and some other things coming in the mail soon.

Eric charged me just over $170 for the full CLA and Meter adjustment. I feel it was a pretty good price and if you didn't over pay originally I would send your camera off to him. For me personally the just under $600 that I paid for a pristine condition camera that I have 100% faith in was worth it. I obviously can't make any statements towards what you find a good value but when you get the camera back from him you can have complete faith in its mechanical stability.

I hope you get everything worked out. So far it's a great camera. Only 3 rolls of film through it but it was already worth every penny for me!

[Denverdad]

Well that puts the final nail in that coffin then! (not that I'm surprised really)

To answer your question mk07138, I did pay a little bit over your threshold for "might get a little peaved." Not by a lot really, but still... So I just sent off a message to the seller to see if he is willing to work with me on this. We'll see what happens.

On the plus side, this camera has already convinced me that I am really going to enjoy 6x7! Aside from its problems, I just love handling the thing. I can't seem to get over the incredibly satisfying "kitch-a-CLUNK" every time I press the shutter (well, when it actually fires properly, that is)! The camera is such a delightfully strange mix - equal parts beauty and beast. It conveys a real sense of precision engineering, but delivered with all the assertiveness of a Sherman tank!

Anyay, I guess if you have one you know what I'm talking about.

Thanks

[Eric]

There are several reason's for the mirror to lock up all the way with the shutter open but the most common reason is the shutter holding magnet. The core of the magnet get's magnetized thus not releasing the second curtain.

[Eric]

If anyone want's to tighten the Pentax 6x7 prism to tighten up just unscrew the two front screws of the prism a couple of turns. This should help.

[Mgarber]

Hi, I've got a 6x7 with the mirror stuck half way, and I can't wind or release the shutter (I've wound it already, but can't release).

At first the mirror got stuck, I took out the battery and put it back in and the mirror released. Now, I somehow lost the battery so I stuck in four Energizer A76 batteries with a bit of tinfoil to fill the space. The battery check light illuminates when i press the battery check button, but the mirror won't budge.

Anything else, like the magnets or something, that would cause the mirror to remain stuck? I'm having a bit of difficulty coming by a proper px28 battery.

[Silent Street]

It is a matter of enduring irritation to me that cameras on eBay are found to be riddled with all manner of problems, even those listed as "mint" or "excellent". Generally a purchase should not be made unless you can return it (in certain countries, the law specifies that the item(s) can be returned if they do not function as intended, not of merchantable quality, falsely conditioned or do not perform as expected — "statutory laws" they are called). I would contact eBay if concerns to the Seller remain unresolved.

I would say from the description tThat camera has been tampered with, obviously. The description of mirror/shutter faulting and the curious position of the exposure counter dial (and what do you think he's been doing around there!?) should alert you to what could well have been a backyard hack-job on the camera. I am thinking the miror/shutter actuation solenoids (and the magnet beneath the shutter button) are on the blink (age-related, but could also be a result of mechanical interference).

Unless the TTL meter is producing noticeably over- or under-exposed images, I would not be too concerned about "excessive play", especially toward the rear where a slight raised profile may be noted, even with sealing in good condition. On the other hand, if the TTL prism is improperly secured or cannot be secured to be safe from springing off inadvertently in normal use, then the foam sealing may need replacement.

Your first priority should be to make at least two rolls' worth of exposures with the supplied lens and scrutinise them (preferably transparency film so you can easily fault over- or under-exposure of images). That will tell you a lot and give you a starting point for further investigations and enquiries.

And eBay... don't believe everything you read on descriptions of cameras. Not ever. Unless you can actually handle the camera before purchase. It's such a darned risky place to do business.

[ElJamoquio]

If you purchased it off of eBay, you can return it if you want.

Just FYI. It doesn't matter if the seller isn't willing to work with you - if he isn't, you open an eBay resolution case, they'll give you the refund, and tell you to ship it back.

You'd be out the shipping price from your house to his.

[Sasha Krasnov]

Hi! To solve the problem you may need to clean the shutter holding magnet and other electrical contacts by yourself. It is not so difficult. I've wrote an article about it: Pentax 6X7 & 67 mirror stuck repair ? SKrasnov.com. I hope it may help everybody with the same problem.

[Silent Street]

Hi! To solve the problem you may need to clean the shutter holding magnet and other electrical contacts by yourself. It is not so difficult. I've wrote an article about it: Pentax 6X7 & 67 mirror stuck repair ? SKrasnov.com. I hope it may help everybody with the same problem.

A related question is how the shutter holding solenoid gets "dirty" in the first place! The mechanism is very, very well sealed. A common belief is that the mechanism just gets tired, succumbing to that whether it is open or closed (open, operating, closed at rest). The thing is damned if it does and damned if it doesn't!