Olympus OM2n issue

[valdas]

I have just finished my summer vacations - piles of film to develop... I have started with E6 process and developed several rolls. One of them came out clearly underexposed (too dark). I inspected the film - it was shot with my OM2n in auto mode (aperture priority). So I checked the camera. I started with the light-meter - checked against other cameras as well as my handheld reliable Gossen. Light-meter showed correct values. Then I shot a few frames and realised by the shutter sound that actual shutter speed is not what light-meter shows. E.g. light-meter shows 1/15, but actual speed sounds more like 1/30 or 1/60. Camera works fine in Manual mode, just this issue in Auto mode. Of course, I can set an expose compensation to +1 or 2, but still... Service time or any tips for DIY?

 

[chrism]

The meter in the viewfinder is separate from the meter in the body, so it's possible that the viewfinder display says one thing while the off-the-film meter in the body decides differently during the exposure. The viewfinder meter is just there in auto use to give a rough idea of what the OTF meter will do. Of course, in manual mode the viewfinder meter shows you exactly what you're getting as it's you that sets the shutter speed.
If it were a shutter adjustment problem it ought to be there in A or M, so it's probably the OTF meter and its diodes that are crapping out. I don't know if any repair techs can fix that (it would require a donor body with a good meter), but if you're in the US or Canada you could e-mail John Hermanson and ask him. He's at omtech1@zoho.com
Good luck with it!

 

[valdas]

The meter in the viewfinder is separate from the meter in the body, so it's possible that the viewfinder display says one thing while the off-the-film meter in the body decides differently during the exposure. The viewfinder meter is just there in auto use to give a rough idea of what the OTF meter will do. Of course, in manual mode the viewfinder meter shows you exactly what you're getting as it's you that sets the shutter speed.
If it were a shutter adjustment problem it ought to be there in A or M, so it's probably the OTF meter and its diodes that are crapping out. I don't know if any repair techs can fix that (it would require a donor body with a good meter), but if you're in the US or Canada you could e-mail John Hermanson and ask him. He's at omtech1@zoho.com
Good luck with it!

Thanks - very well explained! I am not in US and will need to decide if I want to spend money on repair or just live with with M and/or with A with exposure compensation (it seems to be linear deviation for now).

 

[Richard G]

I know that if the camera is off Automatic exposure will still work but 1/30s is the minimum shutter speed. Could it be a battery issue?

 

[valdas]

I know that if the camera is off Automatic exposure will still work but 1/30s is the minimum shutter speed. Could it be a battery issue?

I doubt battery is at fault - I put fresh Varta batteries just before shooting that particular roll. And also - in A mode slow speeds are still working (1/8,1/4 etc), it is just that they are off by 1-2 stops vs light-meter that is in the viewfinder. Underexposure in all frames was consistent, would that be the case if batteries are near dead? But I will check batteries just in case...

 

[Richard G]

Are you testing with film in?

 

[valdas]

Are you testing with film in?

🙂 what? No, the film is removed now. I am shooting it empty.

 

[ptpdprinter]

Are you testing with film in?

This is key. There are two meters: one in the viewfinder which previews the exposure, and one in the body which reads off the film for actual exposure. If there is no film in the camera, it will be reading off the black pressure plate and the exposure will be longer than the viewfinder meter indicates. The emulsion side of the film is lighter than the black pressure plate.

 

[valdas]

This is key. There are two meters: one in the viewfinder which previews the exposure, and one in the body which reads off the film for actual exposure. If there is no film in the camera, it will be reading off the black pressure plate and the exposure will be longer than the viewfinder meter indicates. The emulsion side of the film is lighter than the black pressure plate.

But the actual exposure is shorter, not longer.

 

[vbsoto]

Check your lens that the aperture is not sticking as well.

 

[valdas]

Check your lens that the aperture is not sticking as well.

Nope, lens is fine - CLA'd recently.

 

[chrism]

This is key. There are two meters: one in the viewfinder which previews the exposure, and one in the body which reads off the film for actual exposure. If there is no film in the camera, it will be reading off the black pressure plate and the exposure will be longer than the viewfinder meter indicates. The emulsion side of the film is lighter than the black pressure plate.

Absolutely correct. All bets are off if you try to figure out if the OTF meter is right without any film to meter from! But the OP said he had a film that came out underexposed - and others of the 'several rolls' were OK. So it might be an issue with the development of that particular film. On the other hand, he says the shutter speeds sound wrong, which is inarguable if we assume he knows what 1/15 sounds like versus 1/30 or 1/60. If that's correct (and I prefer to give the benefit of the doubt), then the camera needs a service.
My recommendation would be to expose another film and see if the underexposure recurs, in which case a service is definitely needed.

 

[valdas]

But the OP said he had a film that came out underexposed - and others of the 'several rolls' were OK. So it might be an issue with the development of that particular film. On the other hand, he says the shutter speeds sound wrong, which is inarguable if we assume he knows what 1/15 sounds like versus 1/30 or 1/60. If that's correct (and I prefer to give the benefit of the doubt)

Other rolls were from other cameras. The only underexposed roll was from OM. And I am pretty sure I can tell 1/15 from 1/30... 🙂 in the army I did Morse code as a "sport" - speed transmitting and receiving. Dots, dashes, pauses in between was something I did very well and won several competitions.

 

[chrism]

Other rolls were from other cameras. The only underexposed roll was from OM. And I am pretty sure I can tell 1/15 from 1/30... 🙂 in the army I did Morse code as a "sport" - speed transmitting and receiving. Dots, dashes, pauses in between was something I did very well and won several competitions.

So I was right to believe in you! Your camera needs a service, unless you are happy to use it with manual metering.