Olympus OM-2n and power consumption

[zanxion72]

I tend to forget my lovely OM-2n with the switch left to Auto or Manual. With the lens cap on, how soon the batteries will go flat? Are there any other drawbacks besides power consumption to this?

 

[OlyMan]

I can't give you an exact duration, but without moving the switch to Off, the metering circuits will remain powered up. They're not digital computers churning away in the background like modern cameras which are basically a PC with a lens, but they will still flatten the battery quicker than if you turn the switch to Off. Also if you're the type of photographer who immediately winds on after a shot, you could more easily trip the shutter, wasting a shot. If the shutter gets accidentally tripped in Auto position with the lens cap on, the camera will leave the shutter open to try to get enough light on the film, for as long as two minutes I think on the OM-2. This will also more quickly flatten the batteries because of the drain on power from the electromagnet which holds the second curtain open.

 

[zanxion72]

Thanks! I did not think of that, tripping the shutter in auto with the cap on! Thank you for the advice!

 

[OlyMan]

Thanks! I did not think of that, tripping the shutter in auto with the cap on! Thank you for the advice!

Call it benefiting from the experience of my previous 'whoops' moments. It's one of the main reasons I don't wind on until I'm ready to take a shot. Unlike your OM-2ɴ, none of my OMs have a true 'off' mode and all the lot of them will happily trip their shutters if the shutter button gets knocked. The shutter button also turns on the meter circuits in the OM-2SP, OM-3, OM-4 and OM-40/PC, and is the main reason those cameras have a reputation for being battery-munchers if users don't remember to turn the shutter speed dial to 'B' while in storage.

 

[wiltw]

I believe the om2n is like the om one in using the mercuric oxide battery which are known to last a year without benefit of an on-off switch on the camera. it is only after cameras started to use silver oxide or lithium batteries that the on-off switches became necessary to prolong battery life more than a few months especially in cameras like the original OM4. In part, because the om one and om2 are mechanical cameras and use the battery only to power the meter whereas later cameras resorted to electronic shutters.

 

[AgX]

The issue is not the type of cell, Mercury or Silveroxide. (Though Silveroxide cells have a larger energy-density.)
It is the light depending resistor (photoresistor). It has even in complete darkness no infinite resistance. Thus without a switch the metering circuit will drain the cell a bit.

 

[MattKing]

The OM-2n uses silver oxide cells - not the mercury cells used in the OM-1 or OM-1n.
The OM-2n (as well as the OM-2) also doesn't have a true "off" mode, in that even if it is switched to "off", if you trip the shutter it will engage the off-the-film metering system to control exposure. That exposure will, however, be limited to no longer than 1/30 second if the switch is turned to "off'". That battery protection feature is built into both the OM-2 and OM-2n. You can find reference to it on page 13 of the OM-2n's manual.
If the lens cap is on and you trip the shutter when the switch lever on the OM-2n is turned to AUTO, the off-the-film exposure system will extend the exposure to up to 120 seconds.

 

[E. von Hoegh]

I believe the om2n is like the om one in using the mercuric oxide battery which are known to last a year without benefit of an on-off switch on the camera. it is only after cameras started to use silver oxide or lithium batteries that the on-off switches became necessary to prolong battery life more than a few months especially in cameras like the original OM4. In part, because the om one and om2 are mechanical cameras and use the battery only to power the meter whereas later cameras resorted to electronic shutters.

The OM2 has an electronic shutter, uses silver oxide cells, and mine got about three years per set of cells. I had a set of Varta mercury cells last from 1998 until 2015 in a LunaLux lightmeter.
The early OM4s -had one- ate cells due to an electronics defect.

 

[zanxion72]

Amazing! I have learned about the OMs more than I have bargained for. I came down to the OMs from the Canon cameras. My first one was the low end OM-10 that got me very dissapointed in terms of flexibility, even with the manual adapter installed. Then I was gifted an OM-4Ti and it amazed me being lightweight and as capable as my Canon New F-1. Then I just could not say no to a like new OM-2n with its beautifull brown case. I have read that it can shoot perfectly metered shots even with the switch set to off. Is that true? Are there any limitations to that?

 

[MattKing]

I have read that it can shoot perfectly metered shots even with the switch set to off. Is that true? Are there any limitations to that?

Yes, but only if the off-the-film metered shutter speed is 1/30 second or shorter.
This is for the reasons indicated above respecting avoiding battery drain when the shutter is released with the lens cap on..
By the way, if there is no film in the camera and you release the shutter on Auto, the exposure will be quite long. The off-the-film metering depends on there being film there to reflect the light.
And that off-the-film metering works with flash as well - provided the flash is appropriately dedicated.

 

[zanxion72]

Yes, but only if the off-the-film metered shutter speed is 1/30 second or shorter.
This is for the reasons indicated above respecting avoiding battery drain when the shutter is released with the lens cap on..
By the way, if there is no film in the camera and you release the shutter on Auto, the exposure will be quite long. The off-the-film metering depends on there being film there to reflect the light.
And that off-the-film metering works with flash as well - provided the flash is appropriately dedicated.

When I bought the camera and trying to test the auto, I thought that there was a problem with it as the shutter seemed unusually slow with what I would expect from the sunny-16 rule. This explains it perfectly, and lets me run the rest of the test film in it as nicely as I can, without worrying for the exposure! A real releaf after reading this. A nice reminder that reading the manual is not a bad thing.
Thank you so much!

 

[OlyMan]

Amazing! I have learned about the OMs more than I have bargained for. I came down to the OMs from the Canon cameras. My first one was the low end OM-10 that got me very disappointed in terms of flexibility, even with the manual adapter installed.

You mean you upgraded OM-10 was really only intended as a beginners' SLR to be used in aperture priority. The plug-in manual adaptor was always a bit of a half-hashed afterthought and was really just a box-ticking exercise. That said, other than obviously my OM-1ɴ, I can probably count the number of times I've used my cameras in manual mode on one hand.

 

[zanxion72]

You mean you upgraded OM-10 was really only intended as a beginners' SLR to be used in aperture priority. The plug-in manual adaptor was always a bit of a half-hashed afterthought and was really just a box-ticking exercise. That said, other than obviously my OM-1ɴ, I can probably count the number of times I've used my cameras in manual mode on one hand.

Let it be called an upgrade, it is more like GAS. I am mostly using them in manual. I find it faster to compensate for the shadows/highlights. What struck me with the OM10 was that I had no much idea what the camera was doing.
(I still waste a couple of frames "manually" though )

 

[wiltw]

The OM2 has an electronic shutter, uses silver oxide cells, and mine got about three years per set of cells. I had a set of Varta mercury cells last from 1998 until 2015 in a LunaLux lightmeter.
The early OM4s -had one- ate cells due to an electronics defect.

I need to double-check, but I believe the om2 was indeed mercuric oxide, and it was the OM-2SP which used the silver oxide

 

[faberryman]

The OM2 and OM2n manuals both specify two SR44 1.5v silver oxide batteries.

 

[OlyMan]

I need to double-check, but I believe the om2 was indeed mercuric oxide, and it was the OM-2SP which used the silver oxide

No, only the OM-1(ɴ).

 

[OlyMan]

What struck me with the OM10 was that I had no much idea what the camera was doing.

If you're used to using cameras in full manual mode you would have found the OM-10 frustrating, because the viewfinder display only shows you what shutter speed the meter thinks is correct, not your chosen shutter speed. All the double-digit amateur models work the same way.

 

[MattKing]

If you're used to using cameras in full manual mode you would have found the OM-10 frustrating, because the viewfinder display only shows you what shutter speed the meter thinks is correct, not your chosen shutter speed. All the double-digit amateur models work the same way.

While this is true, in most cases it doesn't matter much. With the OM-G, you still get a "Manu" indicator in the viewfinder. You also get off-the-film automatic, with exposure compensation (including a viewfinder warning), as well as the best implementation of a self timer switch on the OM bodies - all in a body considerably lighter than an OM-2 or OM-1.

 

[zanxion72]

The OM-G might be the next in the line although it has a more modern look. I love the needle of the lightmeter in the viewfinders as it is less distracting than leds for me. How does the viewfinder of the OM-G compares to that of the OM-2n?

 

[OlyMan]

...as well as the best implementation of a self timer switch on the OM bodies

Prefer the lever position on the OM-40/PC if I'm being honest, but I get your drift.

 

[OlyMan]

How does the viewfinder of the OM-G compares to that of the OM-2n?

93% view vs 97%. Both 0.92x with a 50mm lens. Slightly brighter image because like the OM-30 (OM-F) it uses the Lumi Micron focussing screen, strangely omitted from the OM-40 (OM-PC)

 

[Bill Burk]

I always thought it was silly for the OM-1 to have an on-off switch (will that battery last 5 years or three?) But my OM-4 uses so much power I'm afraid to open my PG&E bill.

 

[E. von Hoegh]

I always thought it was silly for the OM-1 to have an on-off switch (will that battery last 5 years or three?) But my OM-4 uses so much power I'm afraid to open my PG&E bill.

It makes very good sense to provide an "off" switch. Exhausted cells are far more likely to leak, and even if you leave the cap on the lens the resistance of the CDS cell is far from infinite.
Pentax used an extra CDS cell and a transistor switch circuit to switch the meter off when the cap is applied in the Spotmatic series, and it actually works pretty well.

 

[Filmsir1]

I have an OM2SP and from what I'm reading above, putting it in B mode will cut down on the power loss right?

 

[Filmsir1]

I always thought it was silly for the OM-1 to have an on-off switch (will that battery last 5 years or three?) But my OM-4 uses so much power I'm afraid to open my PG&E bill.

I wondered the same thing too. I like how you put it. Now my OM-1's meter is inop. My OM-2SP was CLA'd by John Hermanson and he states there is no fix for the drain.