Odd OM-4 electronics behaviour

[xtolsniffer]

I have an Olympus OM-4 - the old style electronics one with the high battery drain. Just recently I've noticed that if I take a spot reading, then the exposure compensation +/- indicator will flash in the viewfinder for a few seconds then stop. Similarly, if I take a shot, then it will flash again after the shutter fires. I wondered if the high current drain of those operations was causing a voltage drop and messing with the electronics to think that the exposure compensation dial had been turned. I switched from LR44 alkaline to good SR44 silver oxide as I think they have a higher current output, but it still behaves the same. It doesn't seem to affect the exposure in any way, but it's just odd and now I know it's there, it irritates me. Does anyone else's OM-4 do the same thing? Unfortunately I have a bit of a history with OM dodgy electronics so I'm waiting for it to suddenly expire with this being a warning-shot.

 

[Svenedin]

I don't have an OM4 but I do have 4X OM4-Ti's and an OM3-Ti. I have had problems with 2 of the OM4-Ti's which may sound bad but it has been over a 27 year period! Both of the problems were electronics related. I had one fixed by OM Doktor in Hamburg, Germany (Frank Timman) and the fault was "electronics repair ASA-auto/manual group" according to his invoice. Something wrong with the switch and ASA dial (where the exposure compensation is as well). My other poorly OM4-Ti is actually with Frank right now.

I just tested one of my other OM4-Ti's and can confirm that the exposure compensation does blink +/- IF exposure compensation is set. It will blink in auto or manual regardless of whether a spot reading is taken. It is to remind that the shutter speed is being influenced by exposure compensation.

 

[xtolsniffer]

Thanks Svenedin, mine blinks if the exposure compensation is set to zero, but ONLY when you take a spot reading or press the shutter. Otherwise it's not visible in the viewfinder unless you set the exposure compensation dial to anything other than zero obviously.

 

[Svenedin]

Hmm. It may need a service soon. There could be dirt under that ASA/ISO dial that is causing a bad connection or something like that. If you need a good chap: OM-Doktor@gmx.de

I could not get my OM4-Ti's fixed in the UK from either Luton Camera or Newton Ellis. They said "we'll look at it but if it needs parts can't do it". I am keen to get all my OM's in tip-top condition whilst there are still people around to service them.

 

[xtolsniffer]

I got mine done by Miles Whitehead, including swapping an old corroded OM-1 pentaprism for one from a salvaged OM-10, he did a lovely job on three OM-1s and that OM-4, but that OM-4 has always been a lemon since the day I bought it. Not as bad as the OM-2n I used to have, but that's a different story.

 

[Svenedin]

I've heard good things about Miles Whitehead. It's tricky with OM4's. There seem to be quite a number of revisions of the main circuit board but like all the OM's they are getting old. I was once offered an OM4 for peanuts but I'm afraid to say I turned my nose up at it.

 

[Bill Burk]

I often see the exposure compensation flashing when I know it’s on the center. I figure it’s dust and I will spin the compensation back and forth a few times. It seems to help for a while.

But if it gets bad, you can have some really unwanted results like a real “several stop” under exposure. That has happened to me in moist environments a couple times. Maybe get it cleaned.

 

[xtolsniffer]

I was hoping that if it was flashing it might be at best a third of a stop out, I can live with that, but I guess if it's flashing and the dial is set to zero you have no way of knowing what exposure compensation might be dialed in...

 

[E. von Hoegh]

I often see the exposure compensation flashing when I know it’s on the center. I figure it’s dust and I will spin the compensation back and forth a few times. It seems to help for a while.

But if it gets bad, you can have some really unwanted results like a real “several stop” under exposure. That has happened to me in moist environments a couple times. Maybe get it cleaned.

"Moist environments"...
That could be an accumulation of dust in just the wrong area. Say on the switch, or any place contacts or conductors are exposed; the dust gets damp, conducts just enough to confuse things. I had that issue with a Sony portable allwave radio, cleaned all the pcbs and controls & it came back to sanity.

 

[OlyMan]

You may be having problems with current-drop. The baseplate on the camera forms part of the camera's electrical circuit and any dirt or corrosion to the screws or threads inhibits current flow. When you perform an action that demands sudden high current (such as firing a shot) the camera can misbehave as a result.

Remove the battery cap and take out the batteries. Remove the winder cap. Take off the baseplate by removing the four tiny cross-head screws: two either side of the tripod socket, and one at each end. If present, be careful not to lose the weather-seal gasket round the motor-drive electrical contacts (it will probably be stuck to the underside of the baseplate). Twist a cotton-bud (Q-tip) moistened with alcohol or lighter fluid into each screw hole in the baseplate. Use it to clean the screws and the screw threads in the chassis, also run it round the perimeter of the threads on the battery cap and round the threads which the cap screws into. Replace the baseplate ensuring the four screws are very tight, but don't strip the heads. Replace the batteries with known good ones and replace the caps.

For me, this cured an intermittent problem where my Ti behaved as though the batteries were going flat, including the symptoms you described and the electronics 'rebooting' when I fired a shot or used the display-illumination.

If this solves the problem, it's been a cheap fix. If it doesn't, it will have done no harm and was still worth the effort.

 

[Svenedin]

You may be having problems with current-drop. The baseplate on the camera forms part of the camera's electrical circuit and any dirt or corrosion to the screws or threads inhibits current flow. When you perform an action that demands sudden high current (such as firing a shot) the camera can misbehave as a result.

Remove the battery cap and take out the batteries. Remove the winder cap. Take off the baseplate by removing the four tiny cross-head screws: two either side of the tripod socket, and one at each end. On a T/Ti model, be careful not to lose the weather-seal gasket round the motor-drive electrical contacts (it will probably be stuck to the underside of the baseplate). Twist a cotton-bud (Q-tip) moistened with alcohol or lighter fluid through each screw hole in the baseplate. Use it to clean the screws, the screw threads in the chassis, also run it round the perimeter of the threads on the battery cap and round the threads which the cap screws into. Replace the baseplate ensuring the four screws are very tight, but don't strip the heads. Replace the batteries with known good ones and replace the caps.

For me, this cured an intermittent problem where my Ti behaved as though the batteries were going flat, including the symptoms you described and the electronics 'rebooting' when I fired a shot or used the display-illumination.

If this solves the problem, it's been a cheap fix. If it doesn't, it will have done no harm and was still worth the effort.

Very good idea! I had issues with an OM4-Ti some years ago. The screws near the tripod socket had become loose from frequent use on a tripod. Tightening them solved the problem but your solution is much more comprehensive and better.

Stephen

 

[OlyMan]

Thanks Stephen. Hope it helps the OP, but if it doesn't cure his particular problem, it won't have done any harm to try it as a cheap fix.

 

[xtolsniffer]

Great suggestion! I'll give it a go. I've taken the baseplate off a few OMs in my time so I'm happy to try. I did wonder if it was a voltage drop as it only seems to happen when I do something that requires current. I'll let you know if it works.

 

[OlyMan]

Let us know if it works. I remember about ten years ago there was a contributor on the Amateur Photographer forum who was reporting issues with his 4Ti behaving like the batteries were always weak, and after a pageful of suggestions it came out in the wash that he'd stripped and resprayed the heavily scratched and chipped baseplate with aerosol stove-paint but had neglected to scrape the screw holes back to bare metal. It's an easy schoolboy-error to make unless the penny drops that the baseplate is a functional part of the camera's electrical circuit.

 

[Svenedin]

Let us know if it works. I remember about ten years ago there was a contributor on the Amateur Photographer forum who was reporting issues with his 4Ti behaving like the batteries were always weak, and after a pageful of suggestions it came out in the wash that he'd stripped and resprayed the heavily scratched and chipped baseplate with aerosol stove-paint but had neglected to scrape the screw holes back to bare metal. It's an easy schoolboy-error to make unless the penny drops that the baseplate is a functional part of the camera's electrical circuit.

Interesting story. The paint is not very good on OM4-Ti's. I call the scratches and dents "patina".

 

[OlyMan]

You dented one? That's actually quite impressive.

 

[Svenedin]

You dented one? That's actually quite impressive.

Just the film memo holder is a bit bent, lots of scratches and paint loss, brassing. That camera has been around Africa, up Mount Kenya, in Australia, New Zealand and the back of beyond in the USA so it's allowed to reflect that. I have had it for 27 years!

 

[OlyMan]

With regards to the paint, I think Olympus never really got the hang of using a paint formula that stuck well to the titanium. After their first attempt with the champagne 4Ti's they switched to black in the early 1990s, and as much as trying to keep up with fashion trends, I had wondered if it was their first attempt to use a more resilient paint formula. However that didn't work too well either, and so by the time the 3Ti was launched in 1995 they chose to anodise it. Yet they continued to finish the 4Ti with the same black paint until the bitter end. Which is a bit bizarre really, because that meant they must've kept two different paint and finishing lines open when one would have sufficed.