Mamiya 645 1000s mirror locks up only with film loaded

[lozpop]

Hi, my Mamiya 645 1000s works perfectly without film inside. The mirror never gets stuck in the up position, but with film inside, only sometimes the mirror gets stuck in the up position. I’m a newbie with film cameras so I don’t know if maybe I’m loading the film the wrong way. I’ve watched many videos on how to load film so I’m not sure if there’s anything I might be doing with the film that causes the mirror to get stuck.

 

[Donald Qualls]

Are you sure you aren't accidentally triggering the MLU (mirror lock up) feature? This is built into the camera to reduce vibration when tripping the shutter, intended to improve sharpness for long exposures.

 

[lozpop]

Hi Donald, thanks for suggesting that, although no, I’m not using the mirror lock-up mode. That is actually the only way I can unstuck the mirror. I move the lever to the mirror lock-up mode and then back to “normal”. It’s really interesting that it happens only with film inside though

 

[MattKing]

Welcome to Photrio.
Is the (empty) film insert inside the camera when you are checking how the camera acts without film?

 

[lozpop]

Yes, the empty insert is inside. The weird part is that when the mirror gets stuck in the up position, pressing the battery check button doesn’t unstuck it (as explained in the manual).

 

[lozpop]

I’ve also thought about the battery but the green light turns on. I’m shooting at 59 degrees F (15 Celsius), I hope that’s not a problem.

 

[reddesert]

1. Fresh battery - although if this were the only problem, pressing the battery check button should release the mirror. Still a good idea to test with a very fresh battery.

2. In order to cock and fire the shutter without film loaded, you need to have the multiple exposure switch set to multi. So the situations with and without film are somewhat different. Perhaps there is something about your film loading or about the engagement of the film wind gears with the insert that is preventing the cycle from completing.

 

[lozpop]

Right now I’m going through a film and it only happened on the first shot. Now I’m at number 6 and it hasn’t happened again.

That’s also the problem. I can’t seem to recognize a pattern. And I have 30 days to return the camera for a refund, so I’m trying to understand if it’s something I do wrong or if it’s a real issue — I also have to check the first film I’ve done to see if the photos came out when the mirror got stuck (I don’t know if the shutter got stuck too)

 

[lozpop]

1. Fresh battery - although if this were the only problem, pressing the battery check button should release the mirror. Still a good idea to test with a very fresh battery.

2. In order to cock and fire the shutter without film loaded, you need to have the multiple exposure switch set to multi. So the situations with and without film are somewhat different. Perhaps there is something about your film loading or about the engagement of the film wind gears with the insert that is preventing the cycle from completing.

I’ve ordered a new battery even though the one I have inside is basically new, so yes I will test that

About the multi-exposure, yes, when I have no film inside, I use the multi-exposure mode to test if the camera is shooting properly (as I read in the manual).

How can the film insert prevent the mirror or shutter to not complete the cycle though? Aren’t the 2 things two separate processes? The film properly goes to the next frame and is set in position before shooting.

 

[MattKing]

These cameras are battery reliant - check and clean the contacts. They work with the alkaline batteries, but prefer the longer lasting, more expensive and harder to find silver oxide ones (which were the most easily found back when the cameras were new).
The inserts and the bodies communicate in a number of ways - all mechanically. But the electricals also play a role when it comes to the safety interlocks.
Having film installed could affect the placement of an insert that is bent or damaged (or installed in a bent or damaged camera), which in turn could affect that communication, which in turn could affect whether the camera knows to lower the mirror.
If you were local, I would loan you another insert (in a socially distanced manner of course) to allow you to check to see if the insert is the source of the problem.

 

[lozpop]

These cameras are battery reliant - check and clean the contacts. They work with the alkaline batteries, but prefer the longer lasting, more expensive and harder to find silver oxide ones (which were the most easily found back when the cameras were new).
The inserts and the bodies communicate in a number of ways - all mechanically. But the electricals also play a role when it comes to the safety interlocks.
Having film installed could affect the placement of an insert that is bent or damaged (or installed in a bent or damaged camera), which in turn could affect that communication, which in turn could affect whether the camera knows to lower the mirror.
If you were local, I would loan you another insert (in a socially distanced manner of course) to allow you to check to see if the insert is the source of the problem.

Thanks MattKing. Although isn’t it curious that in the current film it only happened on the first shot and not in the following 9 exposures?

 

[reddesert]

About the multi-exposure, yes, when I have no film inside, I use the multi-exposure mode to test if the camera is shooting properly (as I read in the manual).

How can the film insert prevent the mirror or shutter to not complete the cycle though? Aren’t the 2 things two separate processes? The film properly goes to the next frame and is set in position before shooting.

First, thank you for reading the manual. Next, I don't know exactly how the film insert could prevent the mirror from returning, but obviously there is an interlock, since the shutter and mirror have to finish before the film can be wound to the next exposure. And you reported there is a difference in behavior with film in. Without pictures, it is difficult to know if anything could be amiss in how you load the film or how the insert is seated in the camera.

Since you have a return privilege on the camera, the most straightforward answer is "no, it shouldn't do that," but I understand that these aren't as easy to find as they used to be, so there is an incentive to identify the cause.

 

[lozpop]

Thanks reddesert. I will go through the 5 films I have and see if the problem keeps occurring. If yes, I will probably return the camera, sadly.