OM2 shutter speed problem..why?

Discussion in 'Olympus' started by gabriel_p., Dec 2, 2005.

  1. Hello guys! I have an OM2(n) bought last year mint, but now I noticed
    that the shutter speeds are not precise (anymore?), as they vary
    randomly at a given setting. I mean if i set the ss at 1/60, it may
    happen that out of 5 exposures one would be overexposed - shutter
    going slower, or maybe more than one.
    At slower speeds (say 1/15) the variation is even greater, it's hard
    to get two identical exposures one after another, although without
    much difference between them, but i expect precision from this camera.

    Have you ever had troubles with the shutter speed on your OM? Is the
    all mechanical OM1 less prone to shutter problems than the OM2?
    What could be the cause for this shutter speed problem? And what can
    be done to fix it? Can the battery have anything to do with this?

    I know i'm asking a lot of questions but please try to answer if you
    can, because i really love this camera and i want to understand what's
    happening with it.

    Thank you!
  2. I've never heard of this - with the OM-1, yes: because of its mechanical speeds. The OM-2 is all electronic except for one speed, 1/60, which you can get if you use it with no batteries. I cannot see how an electronic speed selectoer could even do this. You'd best be taking it in for a service...
  3. Are you sure that the cause of the overexposure is the shutter speed varying? Have you put it on a shutter tester (or the "TV Screen" test) at manual speeds and observed the variation?

    Does this happen with all lenses? From your description of intermittent overexposure, it sounds to me not like the shutter but the lens diaphragm failing to close down fully. This would cause more problems when a small aperture is selected, and might be intermittent in occurrence besides.

    You also mention that you are shooting at manual speeds. Do you see a similar effect on Auto? The OM2's OTF metering system will automatically correct for a lens diaphragm failure, if the correct exposure can be achieved within the camera's 1/1000 second fast-end limit.
  4. You made a very good point there, but i'm sure the shutter is the problem. I mean you can tell the difference between the speeds by the sound delay. You can hear it. And my lenses are ok, no problem with those. And as for the auto mode, i don't use it too often, i'm on manual usually.

    So afterall, what could be the cause for this? Electric problem? Should i go fishing for an OM1 body?

  5. I wouldn't go by sound: check it against your TV screen - this only works at the higher speeds, but at 1/1000 a small variation will be very easy to spot.

    The sound can be affected by things like a sticky mirror mechanism, or the mirror sticking to the foam in front of the screen.

    If it really is in the shutter timer, I think the likely cause is a failing capacitor.... the open time is set by the time it takes to charge a capacitor through a set resistance (the resistance is different for each speed on the dial). Another possibility is a poor connection at the resistor where it is selected by the shutter speed dial - I haven't looked at exactly how this is done, whether it might just get dirty with non-use. You might try working the shutter speed dial back & forth through its range a few dozen times and see if that makes a difference.

    This electrical stuff is not my strong area. If you want a camera that will still be working when your son passes it on to your grandson, I'd get an OM1 -- especially if you aren't using the AUTO function anyway.

    rick :)=
  6. Hi Gabriel,According to my past experience with my OM2, the problem is at the electronic circuit, and with time it will agravate. The camera should be hospitalized at an authoritative Olympus surgeon.

    As for your precision expectations from the camera, having been bought mint, you are right. The OM2 is a high pro-caliber SLR and there is no point at all in looking for other OM model since there is nothing wrong with the OM2 model per se. On the contrary. Therefore, in case you decide instead to buy another body, you can consider buying the same, this time from a better source ,in order to keep the former body for parts.

    I suspect the real mint side of what you bought was the cosmetics, like my case. It seems that damaged electronic circuit problems become apparent after some time, when the previous and hidden economy surgery by the guy who sold you the camera, doesn't last any more.

    Fortunately, prices of SLR equipment are free-falling these weeks as never before.


  7. The mechanical OM-1 can develop similar symptoms, but the cause is different and it can be easily re-tuned apparently.
  8. The OM1 in my experience is an exceptionally good camera for stable speeds over time. In many ways the camera is a little difficult to service, but they took pains to make the speed timer easily accessible, much more so than in most other SLRs, so that if the problem does come up it is a quick, easy fix.

    The irony of this is that, while I have found sluggish and erratic speeds in Leicas, Contaxes, Pentaxes, Minoltas, Mirandas and almost every other type of camera, I have never yet encountered this in an OM1. Maybe I've just been lucky.....
  9. Thank you for your answers... I'll either try to find someone who knows how to fix OMs, or get an OM1... I don't want to switch the system, because I just love Zuiko optics and everything in OM cameras.

    OM forever :)

  10. Hi Gabriel

    I forgot to mention some things. As a lot of time has passed since the OMs were launched new to the market, a lot of experience has been accumulated.

    With some models within the OM line, we know for sure that some deseases were endemic. Thus, with the OM4, not the OM4T, nor the OM4Ti, there is a chronic problem with the electronic circuit producing energy leak menaing quick battery drain. I own two OM4s, one of which can loose all battery energy within a single day without use, and the other loosing all energy after three weeks. I believe there are some OM4s that doesn't loose energy at all, but this is a well known problem, affecting lot of these cameras.


    The OM1 is a lovable camera, (I own a single old but working sample) built with a kind of piston cushioning the mirror vibration to such low level, making it enviable by most of other SLRs, including all further OMs. Besides, the OM1 is the only OM able to function without batteries.

    But there is a, let's say, half-endemic, problem with the OM1 being visible last years and it is the deterioration of cement binding the pentaprism mirrors - all these resulting in a kind of growing fungus like annoyance interfering in lower part of the image you view at the viewfinder (NOT AFFECTING THE FILM IMAGE). It is a well known problem, but I wouldn't term it as endemic as the OM4 batteries drain.

    Fortunately, according to my local authoritative (but not offically Olympus) technician, it is possible to transplant a whole healthy OM2 pentaprism to a sick OM1.

    But, on the other hand, remember that the OM2 and OM2n models are much more advanced cameras than the OM1(n) giving you:

    a) Auto-exposure, UP TO 120 SECONDS !!!

    b) Selection between Manual and Autoexposure

    c) TTL flash metering command

    d} Exposure compensation button

    e) SR or SL button batteries instead of the discontinued mercury battery for the OM1 (replacement batteries fitting the OM1 are being produced, but not the exact type for which the OM1 was originally designed.)

    Nevertheless, many people think that these advantages are not worthwile those of the OM1. What do I think ? I recommend owning both, plus the "flagship" - the OM4Ti (and several other RangeFinders, also designed by Maitani for Olympus, but that's another story).


  11. I have encountered on a few occasions the question: "If you could only have one camera, what would it be?" Since I have over 150, this takes some thought. But after consideration, my answer is "an OM1".

    ...but if I could have TWO, the second would be an OM2.

  12. I seem to recall that the OM-2/2n sometimes has a problem with oil getting onto one of the shutter magnets, the one that controls the release of the second shutter curtain. This causes the magnet to become sticky and the curtain release to become erratic.

    Hopefully this is your problem and all you'll have to do is get the magnet cleaned without having to replace any electronics. I've done this before on an OM-PC and that was a simple repair once someone told me where the magnet was and how to get to it, but I have no idea where the magnet might be on an OM-2.

    In case this is of any use, on the OM-PC the magnet is under the mirror box and requires you to pry up the cover plate at the bottom of the mirror box. Then a quick wipe of the magnet with a teeny bit of rubbing alcohol, reglue the cover plate with a bit of contact cement and you're done.
  13. Ruben said "deterioration of cement binding the pentaprism mirrors -"

    This is not deterioration due to fungus, but due to the foam cushioning material under the prism clamp turning to goo and eating into the silvering of the prism. This will happen to all OM1's and OM2's, I don't know about the others but Rick may.

    James said "I seem to recall that the OM-2/2n sometimes has a problem with oil getting onto one of the shutter magnets"

    As far as I am aware, this is not a common problem with the OM2/n, but is common with the lower spec models such as the OM10, 20 (G), 30 (PC) et al.

    I agree with Rick's advice - check your lens diaphragm mechanism - I have a 50/1.8 that closes completely (allows no light through) when set to f16. Also remember that with no film in the camera, at slow speeds of 1/60 and below, the meter will try and read from the black pressure plate, and at higher speeds, light entering the viewfinder eyepiece will influence the exposure to some extent.

    Also it may help to rotate the film speed index dial a couple of times, as the feeler contacts under it sometimes make poor contact with the PCB tracks underneath, especially if the camera has been left for a long time without these contacts having moved. The exposure compensation setting uses these same contacts.

    Also make sure that your batteries are good, and that the contacts are clean. They may look clean, but you will be surprised.
  14. I think James Lai is the one here to hit the nail on the head, although it is not necessary oil that is the cause.

    I have an OM2, and got into trouble with it due to slow shutter speed. especially the first shots of the day were always overexposed, and sometimes a 1/500 even did 1 sec, but the following shots were much better and better, and later shots i couldn't "hear" a problem. Deteriorating foam, of course, is the problem. Not only was this foam used above the prism, but also on other places where body parts needed to be made fit, so no light would enter the camera, like fitting the back. All this foam doesn't only damages the prism, but also, in a more "broken" state, starts to "dwell" trough the camera. And in my case, got in a VERY VERY tiny amount, between the two poles of the electro-magnet that takes care of the timing of the second shutter curtain. When I carefully manually moved the movable part of this mechanism (e.g. with a pointy wooden cocktail-pricker) I could see that the two metal parts were sticky due to a tiny foam partical there in between. In my case it was a bit of a disaster for the fact that after good cleaning with alcohol, with also compressed air to get the rest of the body clean, the shutter performed PERFECT again, but, after assembling the camera, and using it for a week, EXACT the same problem suddenly occurred, with exact the same cause, so disassembling was necessary again. Not a nice life for someone with deteriorating eyesight. So be sure not to get disappointed due to undetectable parts of foam haunting you. For now, the camera has made a few hundred shutter-releases without problems.

    Reach the electro-magnet (the metal poles of it) by removing the bottom plate in the mirror house (one screw, and some glue, and de-solder a ground wire) I have used a small piece of copper plate (foil), very thin of course, around which i winded one layer of thin cotton with alcohol. When you work with the electronics there, use techniques to deal with electrostatic discharge, and just don't try to touch anything unnecessary there. Very delicate.

    For anyone at this job, success.
  15. Hello!!
    I just bought two om2 bodies, the om2 and om2n. One has a slow shutter on the first and second shots, after that it seems to work fine.. in B the mirror takes about 1/2 second to go back after the shutter button was released.????? In the other one the mirror get stucked only in the first shot, you have to release it with the reset button. A repair man toll me that the om2 has a circuit that controls the shutter speeds and it has to be replaced. But there is no parts for doing this, so dont lose your time....." I have a 24mm 28mm 50mm 100mm 135mm 200mm 300mm zuiko lenses!!!!!! I think i have to go for an om1......
  16. Hi Erik, I have the same problem in slowing down the release of the second curtain by the presence of liquid foam upon the electromagnet. I red your old contribute, and I surprised when you told that after one week from the cleaning the problem happened again. I suppose that the liquid foam penetrated inside the electromagnet and maybe inside other components, so that the cleaning couldn't be resolutive. In your opinion is this possible ? Best, Andrea Guazzora
  17. Good morning... Andrea.

    that is a long time ago that I have been here, really. The analogue problems with my OM-2 are far behind me, although I never got the camera working again. It was simply to much to dig in a second time, and in the mean time I went digital. Still, I have the camera here in my possession.

    What I can remember: cleaning the small surface between magnet-core and lever would get it working again, every time, but in no time the same problem occurred.

    My thoughts are:
    as far as i could see, that foam is also used to light-seal the curtains of the shutter, two long narrow strips on top and below. And since I did not de-assemble the shutter, the stuff is still there to be spread with ever release of that shutter. It is a guess, but I am fairly convinced.

    I do not think that the stuff penetrated the coil & core, since cleaning resolves the problem for a short while.

    I hope this info serves your insight in the problem.

    Erik den Houter

Share This Page