[Jellygeist]

Hey folks,

Was out shooting my 6x7 last night and on the very last frame the mirror didn't come back down so I lost the shot. I figured it was the battery (and was kind of bummed since I only got about 5 rolls out of that battery), but the battery check light came on and the light meter still worked.

Taking the battery out snapped down the mirror. Put the battery back in and the light meter and battery check light both still come on. What's the deal? I should probably switch battery brands if anything.

[desertscape]

Your problem is fairly common. Many of the well used bodies do this. I sent mine to Pentax when they used to repair the 67s and they were able to fix it. I doubt your battery is the problem. Sounds like it is time for the repair shop.

[Jellygeist]

Your problem is fairly common. Many of the well used bodies do this. I sent mine to Pentax when they used to repair the 67s and they were able to fix it. I doubt your battery is the problem. Sounds like it is time for the repair shop.

Yeah, I'm thinking the same thing. There is a place in Winnipeg (2 hour drive) that fixes cameras, old and new alike. I guess I'll call for a quote.

[Silent Street]

One problem could be the mirror solenoid sticking — weakness through the passage of time. That is certainly a service job and if it is the early Pentax 6x7 body, it should not come as a surprise given the age of that camera.

But I thought it was more like you were at the end of a battery life cycle. The procedure for resetting the mirror after battery change is to push the small, recessed "reset" button that on the left of the mirror box (when viewed from the front). Then press the shutter, and wind on. This wastes a frame (unless you are at the end of the roll and wind on after the 10th frame). There is one sure way of getting a nasty surprise of a flat battery when you least needed it: if you have mirror lock up (MLU) on your Pentax 6x7 body, tape the mirror up tab with a piece of tape when storing the camera in a bag — it is very easy for ordinary movement to push this small button, raise the lever and ... FLATTEN the battery at the most inconvenient time. This means of course that MLU, when activated during actual exposures, uses power from the battery.

[Jellygeist]

One problem could be the mirror solenoid sticking — weakness through the passage of time. That is certainly a service job and if it is the early Pentax 6x7 body, it should not come as a surprise given the age of that camera.

But I thought it was more like you were at the end of a battery life cycle. The procedure for resetting the mirror after battery change is to push the small, recessed "reset" button that on the left of the mirror box (when viewed from the front). Then press the shutter, and wind on. This wastes a frame (unless you are at the end of the roll and wind on after the 10th frame). There is one sure way of getting a nasty surprise of a flat battery when you least needed it: if you have mirror lock up (MLU) on your Pentax 6x7 body, tape the mirror up tab with a piece of tape when storing the camera in a bag — it is very easy for ordinary movement to push this small button, raise the lever and ... FLATTEN the battery at the most inconvenient time. This means of course that MLU, when activated during actual exposures, uses power from the battery.

These are good points. It's hard for me to gauge just how old my camera actually is. It's in mint condition so it seems like it never saw any real heavy use, or is a later model of the MLU version. The TTL Prism still has "Asahi" over the Pentax branding. My personal guess is that it is from the early 80s but I'm not basing that on much evidence. It's old enough to be a bit creaky in places even if it was barely used in the last thirty-odd years.

I think the main issue is that it eats through batteries way too fast. I got maybe 4 rolls out of this battery. So either there's an electrical problem somewhere OR what you say is correct and that the MLU button is getting nudged while I slug it around in my backpack. There was still enough juice in the battery to power the meter and the battery check light so maybe there is a short somewhere.

I kind of hope it's the latter as who knows how much it'll cost to fix. I can't call the repair place until Monday so I guess I'll just sit on it until then. I'll scrounge up the money somehow, the camera is such a joy to use that it's worth it.

[Silent Street]

Four rolls from a battery!?
Something is wrong in there. It could be the TTL meter with an open short (?)
Mine is from 1989, also mint/barely used, and the tiny battery was last changed in June 2012, by dint of the MLU having been tripped in the pack (at that time I did not have a spare battery and it made me incandescent with rage!!)
The camera is marked thus, but I have no idea how many rolls have been through it in that time. But many, many more than just 4!

I'm never going to move away from the 67. I love steampunk.

PS: I do like the tempting pic of the dusted caramel chews. Yummo! Were you sampling them too?

[Digitalis]

I got maybe 4 rolls out of this battery.

There is indeed a problem there, as I recall I could manage at least ten times that figure even with heavy use of MLU.

I use silver oxide batteries in mine, they are electrically more stable than alkaline and don't suffer as much under low temperatures like lithium batteries do.

So either there's an electrical problem somewhere OR what you say is correct and that the MLU button is getting nudged while I slug it around in my backpack.

The MLU is indeed easy to activate on the 67, though I have a hard time believing you wouldn't hear that mirror fapping about. By all means get your camera checked out. The solenoid can be a problem, but with such an old camera, even if it is well cared for, can develop electrical issues over time... I just hope it isn't one of the expensive problems.

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Last edited by Digitalis; 09-09-2017 at 02:53 AM.

[Jellygeist]

There is indeed a problem there, as I recall I could manage at least ten times that figure even with heavy use of MLU.

I use silver oxide batteries in mine, they are electrically more stable than alkaline and don't suffer as much under low temperatures like lithium batteries do.



The MLU is indeed easy to activate on the 67, though I have a hard time believing you wouldn't hear that mirror fapping about. By all means get your camera checked out. The solenoid can be a problem, but with such an old camera, even if it is well cared for, can develop electrical issues over time... I just hope it isn't one of the expensive problems.

Yes, I hope it's not one of the expensive problems, either. How expensive are we talking?

---------- Post added 09-09-17 at 11:35 AM ----------

Four rolls from a battery!?
Something is wrong in there. It could be the TTL meter with an open short (?)
Mine is from 1989, also mint/barely used, and the tiny battery was last changed in June 2012, by dint of the MLU having been tripped in the pack (at that time I did not have a spare battery and it made me incandescent with rage!!)
The camera is marked thus, but I have no idea how many rolls have been through it in that time. But many, many more than just 4!

I'm never going to move away from the 67. I love steampunk.

PS: I do like the tempting pic of the dusted caramel chews. Yummo! Were you sampling them too?

Haha, those are actually the "teeth" on the roller of some kind of road work machine!

[Silent Street]

Haha, those are actually the "teeth" on the roller of some kind of road work machine!

Dah—oh!!
OK, sorry. I will put my detail glasses on next time. I can see what you are referring to now from the bigger image!!

---------- Post added 10th Sep 2017 at 10:51 AM ----------

The MLU is indeed easy to activate on the 67, though I have a hard time believing you wouldn't hear that mirror fapping about. By all means get your camera checked out. The solenoid can be a problem, but with such an old camera, even if it is well cared for, can develop electrical issues over time... I just hope it isn't one of the expensive problems.

Erm, but the mirror doesn't "flap about". Once triggered, it goes up and stays up. Inside a pack while walking, or on the back seat of the car it is not noticeable. That tape trick I mentioned ... I adopted it years ago and never have experienced a dreaded MLU trigger since.

Regarding repairs... You have to remember that parts are taken from another like-body so repairs introduce a cycle of redundancy and unreliability in their own right. But the solenoid often doesn't need replacing, just "exercising" and a bit of lubrication, unless it is electrically dead, in which case it is yanked out and a replacement put in. The amount of lubrication is miniscule — a very, very tiny drop, at the time of manufacture/assembly. But the ingress of dirt, dust, moisture, corrosion (from using the camera in salty air environments e.g. by the sea) can in themselves cause much more serious problems.

This site gives you an idea what lies under the cover of the 6x7 and what sort of problems develop over time:
Pentax 6X7 & 67: Mirror stuck repair ? Step-by-step guide & Maintenance
Note the solenoid (in green) and the switch at far right.

[Digitalis]

Erm, but the mirror doesn't "flap about". Once triggered, it goes up and stays up.

i'm well aware of what MLU is and its purpose. I was just being colorful with my language.