M645 super unwanted mirror lock up and/or no shutter release

[dan_price]

Hi everyone, using my second hand M645 for the first time (eBay buy from reputable seller) and

encountering the following problem:

 

After taking 5 or so exposures, I have erratic behaviour of the mirror locking up (I switch to yellow

function to release it) and also after progressing the film the shutter release button has no effect - no

photo is taken.

 

After reading all related forums on this on photo.net, it seems the first thing to try is replace the battery

(even though the battery meter light is working). I hope this is the solution.

 

I'll replace battery tomorrow and repost in this thread, but wanted to see if this has been a usual solution

to a usual problem etc...

 

Any info greatly appreciated, Dan

[bueh]

Cameras do weird things when their battery runs low. Wait and see until tomorrow. Which model are you talking about, by the way?

[dan_price]

Hi Bueh B, the model is Mamiya 645 super with AE prism. got new battery today, also tested

the power of the old battery (which i should have thought of yesterday!) and the old battery

has pretty much the same charge as the new one. As in it's not a dead battery!! hmm.

problem expands... will test new battery after dinner...!

again, any more info greatfully recieved..

Dan

[bueh]

I had troubles in a Super with an insert that had a worn-out gear. So it was neither the camera nor the back, but just a faulty roll film insert which resulted in errors in film advancing / shutter winding when not in multi-exposure mode. So if your problem continues, try a different insert or back and check again.

[dan_price]

ok. tried new battery and same deal. This is what the symptoms are emerging to be: Wind

on to take another picture - everything seems fine ie AE prism working etc - but i depress

the shutter release button and nothing happens. OR the mirror goes up and doesnt come

down (have to switch momentarily to mechanical mode to lower mirror).

 

I managed to fire a shot (with the mirror going up and staying), so released by

momentarily switching to mechanical mode, then, after winding on again, it doesnt even

fire at all.

 

Damn!

Maybe it needs a good clean out? - mirror sticking to foam seals or hinge needs clean? but

when i go to mechanical mode i takes a photo fine (at a fixed shutter speed of 1/60th)!!

For this reason i dont think it is a mechanical fault.

Electronic connection fault?!

 

help

[dan_price]

Thanks B... just tried removing the AE prism (after taking correct reading through it) to see if

it worked without the prism and it does! To confirm: no prism, in normal mode (ie not

mechanical mode) and it fired like it should. i read in another thread that a girl had similar

symptoms (with a 1000s) and found she had to use a silver-oxide battery. And also had a

lock-up when her shutter speed dial on her prism wasn't working. Temporary solution was to

take the light reading with the prism then disengage the prism to expose the photo!

Not great, but maybe the culprit is the ruddy prism!??

thanks again

[bueh]

Dan, I am not really experienced with the Super. And I mostly use my medium format cameras with waist-level finders, with the RZ67 being my weapon of choice. Sounds like a tricky issue, I'd try the silver-oxid battery, clean all contacts of the camera and prism and check the camera with a different back/insert. Good luck!

[dan_price]

OK, next update, now with the prism off (having taken exposure reading with it initially and

then manually setting shutter/aperture) no exposure can be made. All seems fine up to the

point of pressing the button where nothing happens. Exposure can be made no problem in

mechanical mode so i think it could be electronics problem, or a faulty solenoid.

Going to Mamiya specialist camera shop at weekend!

[wayne_crider4]

I would send it back.