Olympus OM-2n Meter Problems

[jtrojek]

Hello, everyone. I have an Om-2n that seems to be giving me problems, suddenly. I used it this past summer on auto with no issues and I felt the images were well-exposed.

This fall, I thought it time to change the light seals and remove the foam from atop the prism. I did these things, and then discovered that the light meter seemed to be reading very low, even when pointed directly at a light. I know that this is an imperfect test, but I grabbed my OM-1n and my OM-1 and pointed them outside at a random spot and the OM-1 was properly exposed at f11 (50mm lens @125 shutter speed), and my OM-1n was properly exposed at f8 (same lens and shutter speed). At least it was close. My OM-2n, however, was properly exposed at f1.8 (on manual mode). I know that this is in no way a precise test, but it does suggest that the OM-2n is significantly off, both just by my own eye, as well as in comparison to my other OM cameras.

At first, the meter needle did not move at all, but then became responsive.

I have not tried to film test the OM-2n.

I do not see any foam that I installed covering any place covering up the light meter. I can take pictures of that, if that's helpful.

When I point it in auto mode at different images with different amounts of light, the meter reading changes and the shutter changes its speed accordingly, so that process seems to be functioning fine. It's just that the readings informing it seem to be off.

This past summer I used Duracell lithium 303/357 batteries and the camera performed well. Since then, I bought new silver oxide 357/sr44 batteries, as I recently read that those must be used and figured that that was a good place to start in terms of trouble-shooting (and moving forward). The camera did not perform any differently and was still off by the same amount.

What are my next steps to try to solve the issue? I was just going to sell the camera for parts as I'm happy with my other two OMs, but have since thought it's worth more to me as a learning experience than the money I would get for it for parts. I have little experience in fixing cameras, but I am mechanically inclined.

Thanks so much!

 

[MattKing]

Welcome to Photrio.
As you most likely are aware, the OM-2n has two metering systems. One provides you with the reading in the viewfinder, while the other works in Auto and reads off the film.
Before you go further, try shooting some film in Auto mode, to see if the second system is working.

 

[Chan Tran]

Yes the OM-2n has 2 metering system. I think if you messed up something it's only the one in the viewfinder. For a test try to meter in manual does it works the same?

 

[jtrojek]

Welcome to Photrio.
As you most likely are aware, the OM-2n has two metering systems. One provides you with the reading in the viewfinder, while the other works in Auto and reads off the film.
Before you go further, try shooting some film in Auto mode, to see if the second system is working.

Thanks for the suggestion. I am aware that it has two metering systems, but I don't know enough in terms of how to tackle it. I will try shooting a roll. I was actually thinking about that, as I thought that I didn't actually know how it was working in real life. It'll take me awhile to do it, but I will. Thanks so much!

Yes the OM-2n has 2 metering system. I think if you messed up something it's only the one in the viewfinder. For a test try to meter in manual does it works the same?

Thanks for the question as well. Yes, it seems to work the same in manual as well.

 

[Sirius Glass]

You can download the Olympus OM-2n from this page: https://www.butkus.org/chinon/olympus.htm
If you find it useful please donate $3US to keep that website operating.

Welcome to APUG Photrio!!​

 

[jtrojek]

You can download the Olympus OM-2n from this page: https://www.butkus.org/chinon/olympus.htm
If you find it useful please donate $3US to keep that website operating.

​

​

Thanks so much! It's a great site. I do have a an original manual for the camera, which is handy. Thanks again

 

[Chan Tran]

You could have the needle jammed with the new foam. Or some of the foam block light reaching the sensor in the viewfinder. Or you camera has been that way for a long time because I think it's still working fine on auto.

 

[jtrojek]

You could have the needle jammed with the new foam. Or some of the foam block light reaching the sensor in the viewfinder. Or you camera has been that way for a long time because I think it's still working fine on auto.

Thanks for the suggestion. I will check it out

 

[BobUK]

The Olympus OM-2N has three modes.
Auto, Manual and OFF.

The OFF mode allows for a quick grab shot.
If the shutter is released when in the OFF mode the automatic exposure will meter for a decent shot.
The difference between AUTO and OFF is that the OFF mode exposure stops in 1/30sec.maximum to save battery exhaustion, and the AUTO viewfinder scale does not appear.

Try a couple of test shots in the OFF mode. It does work.

 

[jtrojek]

Hello, everyone. I have not yet tried a test roll of film, but I think I have some more useful information. I just re-did the light seals in my OM-1n and removed the foal from around the prism. This is the same OM-1n whose light meter was reading similarly to my OM-1 (which I have also replace the seals in). Anyway, my OM-1n is now reading like my OM-2n. Sooooooooo, now I'm thinking that I may indeed have done something to partially block the sensor for the light meter, as suggested. So, before I try a film test, I'm thinking I should check out this theory first. In changing the light seals for the for the film door and the bumpers for the mirror (which were just disintegrating), and removing the foam above the prism, is there a place where I should look to see if I have somehow partially a sensor? I have it in my head that I read somewhere that that can happen, though I don't recall where to look to check that. I thought I put the new foam on right where the old degraded foam came from, but maybe I'm wrong. I also just read in another spot that someone had the same issue as me and ended up replacing the foam again and that fixed it. I'd like to know where the problem area may be so that I can check it out. Or maybe in removing the prism I managed to get something else in the way of the sensors? Now that I have the same problem with two of three cameras after having just replaced the foam, I'm guessing it's something I did, some sort of rookie mistake that by luck didn't happen with the third camera. My guess is that my mistake is simple and silly and can easily be fixed? The only difference between what I did in the three cameras is that the OM-1 I didn’t have to remove the foam above the prism as there was no foam to remove, so I didn’t have to play around with that and remove the prism and what not. I also know that I gave the cameras a little shake up side down to try to dislodge any lingering bits of foam that may be stuck somewhere or other in the camera. Thanks so much!

 

[Buzz-01]

You don't need to put foam back on top of the prism. It is there in some (a lot of) cameras, but it's not needed against light leaks. I've removed it in both my OM-1 and OM-2 cameras and never experienced any issues without the top foam.
That's the first place I'd look if the meter needle is off and you've put back some foam around the prism, since the CdS cells are placed right next to the viewfinder IIRC.
The other cells, which are used during exposure, are in the bottom part of the mirror box and you can't (well possibly maybe you could if you're really clumsy) cover them by placing the foam incorrectly in the top of the mirror box.
That's the reason why others suggest shooting a roll through it on AUTO and see if they come out OK.
The CdS cells next to the viewfinder are used for the needle only and they don't influence the actual exposure when shooting in AUTO mode, the blue cells in the bottom are used during the actual exposure.

When using SR44 batteries, does the battery check report that the batteries are OK? (I use SR44's in mine and they last a really long time).

 

[jtrojek]

You don't need to put foam back on top of the prism. It is there in some (a lot of) cameras, but it's not needed against light leaks. I've removed it in both my OM-1 and OM-2 cameras and never experienced any issues without the top foam.
That's the first place I'd look if the meter needle is off and you've put back some foam around the prism, since the CdS cells are placed right next to the viewfinder IIRC.
The other cells, which are used during exposure, are in the bottom part of the mirror box and you can't (well possibly maybe you could if you're really clumsy) cover them by placing the foam incorrectly in the top of the mirror box.
That's the reason why others suggest shooting a roll through it on AUTO and see if they come out OK.
The CdS cells next to the viewfinder are used for the needle only and they don't influence the actual exposure when shooting in AUTO mode, the blue cells in the bottom are used during the actual exposure.

When using SR44 batteries, does the battery check report that the batteries are OK? (I use SR44's in mine and they last a really long time).

The batteries check as OK. I didn't replace the foam around the prism, just removed it. So, on to shooting a roll of film. Thanks!

 

[gone]

When you say the batteries ck as OK, did you measure them w/ a voltage meter? I bought a multi-meter for $5 at Harbor Freight years ago, and it has paid for itself many times over for checking polarity, voltage, etc. Some cameras/meters need a full charge to be accurate. You could shoot a roll of film and see what you have now, or take it apart again and see if anything obvious shows up.

 

[jtrojek]

When you say the batteries ck as OK, did you measure them w/ a voltage meter? I bought a multi-meter for $5 at Harbor Freight years ago, and it has paid for itself many times over for checking polarity, voltage, etc. Some cameras/meters need a full charge to be accurate. You could shoot a roll of film and see what you have now, or take it apart again and see if anything obvious shows up.

I have a voltage meter, but I didn't use it. After having the issue, I wondered about the batteries (despite the fact that they were new), and I did put in a second pair of newly purchased silver oxide 357/sr44 batteries with the same result.

I actually just decided that I'm going to part with the 2n. I don't really need it as I'm happy with my other cameras.

Thanks everyone for your help. I did actually learn quite a bit, thanks to your advice, and I'm sure I will apply it in the near future, most likely on my 1n. Thanks again!