TXForester
Well-known
Hope this is the correct forum as I do not see a medium format forum for SLRs. I just received my first lens and film today and wanted to check the body operation before loading film. The meter seemed to work in all the modes, but when I tried checking the shutter nothing happened.
Per the instruction manual, I had the rear body cap on, C/S switch set to "S." It did not release in A (auto) or with a manual aperture setting at 1/1000, 1/60 or B. The mode switch and viewfinder display seemed to act flaky after that. Of course my multi-meter isn't working, so I could not test the batteries that way. They powered up a flash, but slowly. I had just bought them 30 minutes earlier. Cheap, Dollar General brand. I found some cheap Ray-O-Vacs tucked in the bag with with flash, and could trip the shutter at 1/1000 and 1/60 with them.
Does the 645 have a battery check? I found nothing in the manual and nothing on the body, so my guess no. Does that mean that I can't trust the LED and viewfinder display? I.E. just because they light up, and I can change modes, does not mean I have enough power for the shutter and film advance.
Per the instruction manual, I had the rear body cap on, C/S switch set to "S." It did not release in A (auto) or with a manual aperture setting at 1/1000, 1/60 or B. The mode switch and viewfinder display seemed to act flaky after that. Of course my multi-meter isn't working, so I could not test the batteries that way. They powered up a flash, but slowly. I had just bought them 30 minutes earlier. Cheap, Dollar General brand. I found some cheap Ray-O-Vacs tucked in the bag with with flash, and could trip the shutter at 1/1000 and 1/60 with them.
Does the 645 have a battery check? I found nothing in the manual and nothing on the body, so my guess no. Does that mean that I can't trust the LED and viewfinder display? I.E. just because they light up, and I can change modes, does not mean I have enough power for the shutter and film advance.
marcr1230
Well-known
I just pulled out my 645 to compare
well - after a few years of no use, there's something up with my camera
there's no BC as far as I know, there is a tiny window under the ME winder on the side that will show red if the shutter is cocked and mirror down
there's also a manual wind port on the side , you detach a knob from the bottom and attach to the side to manually wind/ cock the shutter - the battery can die and leave the mirror up or shutter not cocked.
in my case the LCD is lit when off, when I turn the power switch on and touch the shutter, the LCD blanks and nothing happens.
there also an internal CR1220 battery that stores the settings when the AA batteries are out or detached. mine apparently needs to be replaced, but I'm not sure that would prevent the shutter from firing...
good luck
well - after a few years of no use, there's something up with my camera
there's no BC as far as I know, there is a tiny window under the ME winder on the side that will show red if the shutter is cocked and mirror down
there's also a manual wind port on the side , you detach a knob from the bottom and attach to the side to manually wind/ cock the shutter - the battery can die and leave the mirror up or shutter not cocked.
in my case the LCD is lit when off, when I turn the power switch on and touch the shutter, the LCD blanks and nothing happens.
there also an internal CR1220 battery that stores the settings when the AA batteries are out or detached. mine apparently needs to be replaced, but I'm not sure that would prevent the shutter from firing...
good luck
TXForester
Well-known
I missed the manual accessory winder. Good to know. Hopefully I'll just need fully charged batteries.
thanks
thanks
marcr1230
Well-known
Wow - hard to believe, but I apparently fixed it
in my case I checked the power, all was fine (checked pins of detached grip with multimeter )
I then tried working the 4 pins on the back of the open camera, they apparently sense that the back is attached - pushed them manually and then reattached the back - and the film wound and shutter fires, LEDs inside the finder work!
need to shoot a roll now
in my case I checked the power, all was fine (checked pins of detached grip with multimeter )
I then tried working the 4 pins on the back of the open camera, they apparently sense that the back is attached - pushed them manually and then reattached the back - and the film wound and shutter fires, LEDs inside the finder work!
need to shoot a roll now
Which 645 is this? The original?
ellisson
Well-known
I have the 645 and 645N. No battery check light on either. The battery contact points in the holder should be checked and periodically rubbed with a pencil eraser to remove any early corrosion, which though not visible can affect power to the camera.
marcr1230
Well-known
Mine is an original
Quiet it is not !
Quiet it is not !
TXForester
Well-known
Mine is the original.
TXForester
Well-known
Good to hear.
It's worth noting that page 15 of the owners manual advises that a film must be loaded in order for the original 645 shutter to operate. If your 645 won't operate it might be this simple. More about the power supply to the camera follows shortly.
Cheers
Brett
Cheers
Brett
Right. I enquired because when Pentax made the original 645 they included a big booby trap that can render the camera non-functional if it is incorrectly handled. More below.
I acquired an original 645 a few years ago. It was a freebie, which was good, because nothing came of it.
The owners manual mentions the presence of the two battery systems: the AAs in the grip, and the memory battery under the hatch in the bottom of the body. If the memory battery needs to be changed, they instruct you to take it to a service centre.
I wasn't going to do that when I got mine. How hard could it be to change a battery, right? Well, not very hard, at all, actually. But...
I replaced the memory cell easily enough. But afterwards the camera wouldn't function. The reason why wasn't easy to find, but after a fair bit of googling I found some leads via photonet. Here is one relevant thread. Note, please, the second post particularly.
The memory chip used by Pentax to store the software for the camera functions has to be powered, either by the lithium cell or the AA cells in the grip. If it is de-powered, it's wiped, and your 645 will become a paperweight. This is why the manual advises taking the camera to "an authorized Pentax service facility" for replacement of the memory battery.
Maybe Pentax agents can still reprogram your 645 for you (or maybe they can't, so many years after manufacture). In my case I didn't look into it, but I wouldn't assume it's possible without first investigating. If you do happen to follow it up, though, I'd be curious as to how you get on, just for future reference.
Given the age of these bodies I'd not be at all surprised if some of them are non-functional. If your 645 won't respond to activation of the control buttons etc. even with fresh AAs installed, this might be why. I'm not suggesting that this is the case for either of the original 645 owners who have posted above, but merely mentioning this issue for their information and to caution them.
It is possible to replace the memory battery yourself but it is critical—repeat—critical, that the body is powered up with fresh AAs in the grip and the power switch is turned "ON", prior to removing the memory cell. Doing this will power the chip directly from the AA main power supply, during the process of removing and replacing the CR1220. (See this thread at MFLenses Forum for reference to the importance of the switch position).
In my case I was not aware of the significance of this. I removed the memory cell to replace it. Whether I: simply didn't have any batteries in the grip; didn't have the power switch set to ON, or; had no AAs installed with the switch set to "ON"; the bottom line is I wiped all the programming (we are going back a few years, now, hence my inability to be specific). It was only after the camera wouldn't function that I eventually worked out what I'd done.
I have read of a couple of owners who actually had all batteries (AAs and lithium cell) removed simultaneously and replaced them without incident. So I suspect the circuit includes a capacitor that stores a limited amount of power from the batteries. Perhaps their capacitors stored enough juice during the period there was no battery supply connected, and they simply didn't turn the main power switch on, and, thus, avoided tapping the capacitor? Maybe their capacitors were simply in better condition that other owners'? I don't know—I am not an expert on the Pentax 645 circuitry—I'm simply describing my experience with one. I suspect that I may have had both battery types removed with the power switch "ON", exhausted the capacitor, and de-powered the memory. In any case, it was fatal to this older model camera that I had zero interest in getting professionally serviced.
It was an annoying lesson, but being a 645 camera (not a format I've ever really clicked with) and not having a mirror lock up or pre-release, the 645 wasn't a camera that greatly appealed to me even though, in general, I rate Pentax products highly. I scored it in a box of sick or dead bodies and lenses, so it was a challenge to try and get it working again. One which, obviously, I failed dismally! I'm sure the SMC-A 80mm f/2.8 Pentax lens it came with would have been an excellent performer, and I certainly would have run a roll or two through it had I got it going, but would have then moved it on. Ah well.
Please note the lesson I learned the hard way, lest you inadvertently repeat it. If you do change the lithium cell, keep the power switch "ON", ensure the grip is correctly attached, feeding power from the AAs to the body, and then, take great care not to bump the switch to "OFF" during the replacement process. And if you bugger your 645, please do not blame me—all care taken, but no responsibility accepted, etc—I'm simply passing on this information for your attention as it seems an easy trap to fall into.
Cheers,
Brett
marcr1230
Well-known
I find this really hard to believe
My camera was purchased in 1987-88 , I'm the original owner and that would
Make the lithium battery 29 years old.
It's never been replaced and I haven't always had AA batteries loaded
In any case - I will replace it just to be safe for the next 30 years , leaving the main switch on. Thanks for the warning - but I'm skeptical
My camera was purchased in 1987-88 , I'm the original owner and that would
Make the lithium battery 29 years old.
It's never been replaced and I haven't always had AA batteries loaded
In any case - I will replace it just to be safe for the next 30 years , leaving the main switch on. Thanks for the warning - but I'm skeptical
Be as skeptical as you wish. A little skepticism is often a good thing. In fact, you are probably the ideal candidate to definitively disprove the hypothesis (for want of a better term) by actually doing all the "wrong things" detailed above (original owner, lithium cell known to have never been replaced). If you do take the cells out of yours and play with the switches, please let us know the result.
I'd be happy to stand corrected, and have merely recounted my direct experience, and conveyed what information others have stated on the web. I've professed no expertise on the model. I had a Pentax 645 that was trying to work, similar behaviour to what TXForester described above, before removing the batteries (as I described) after which it was completely dead. I suppose it's possible I might have imagined the whole experience, otherwise, perhaps you're implying I've made my experiences up? That is putting it a bit nicer than saying that you think I'm lying. Cheers
Brett
marcr1230
Well-known
Not saying anything about lying , hardly
It's possible the symptoms you describe had a different cause
I just can't believe the camera would brick in the absence of power
In fact , when checking my grip, I found power flows to the camera whether the
Main switch is on or off ( different pin outs )
Also the firmware to the extent it exists is unlikely to
Exist only in volatile memory
In any case , while skeptical, I will heed your warning
Thanks
It's possible the symptoms you describe had a different cause
I just can't believe the camera would brick in the absence of power
In fact , when checking my grip, I found power flows to the camera whether the
Main switch is on or off ( different pin outs )
Also the firmware to the extent it exists is unlikely to
Exist only in volatile memory
In any case , while skeptical, I will heed your warning
Thanks
TXForester
Well-known
Thanks, and page 14 tells you how to check it with the rear body cap.
TXForester
Well-known
I'm curious as to what makeshift tool to use the take the cap out of the lithium battery bay. Looks like the proper tool is fork that goes in the little holes of the cover.
If you have one, a lens spanner with pointed tips is the shot. Otherwise, a pair of budget circlip pliers, with sharpened tips, if necessary, should be perfectly adequate for this purpose given the infrequency of their likely usage. You will simply need to use a little more care to prevent the points slipping out of the holes with a set of pliers. It's unlikely to be particularly tight, if it proves to be problematic some gentle heat from a soldering iron may help break the grip.
Cheers
Brett
TXForester
Well-known
Thank you for the advice.
mwoenv
Well-known
A pair of snap ring pliers works well to remove the battery cover. I got a set with several different tips on ebay for about $5.
I replaced the CR1220 battery in 2013 after purchasing the camera from KEH in 2008. I had no idea how old the battery was but when I removed it and checked it the battery was at full voltage. I didn't need to replace it but I did anyway and plan to do so every 5 years.
I'm very sure I did not have the power switch on when I replaced the CR1220 but I know the 6-AAs had plenty of power and I had no problem. But it probably wouldn't hurt to move the power switch to On when changing the CR1220, based on SH's information.
Great camera and lenses, I hope to use it for a long time to come.
I replaced the CR1220 battery in 2013 after purchasing the camera from KEH in 2008. I had no idea how old the battery was but when I removed it and checked it the battery was at full voltage. I didn't need to replace it but I did anyway and plan to do so every 5 years.
I'm very sure I did not have the power switch on when I replaced the CR1220 but I know the 6-AAs had plenty of power and I had no problem. But it probably wouldn't hurt to move the power switch to On when changing the CR1220, based on SH's information.
Great camera and lenses, I hope to use it for a long time to come.