Another Mercury Battery Question?

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Hi All, While I'm a "classic" camera user of long standing, I'm new to the Konica system. I just picked up a truly beautiful mint Autoreflex T outfit, and I'm delighted, and amazed, and the high standard of the engineering and the quality of construction. However, my initial meter readings have me a bit concerned. The camera arrived with new 1.5v alkaline batteries installed, and the meter is hopelessly "overoptimistic" when compared with my other SLRs and my Minolta spot meter: where the meter of my Spotmatic F (with fresh 1.35v mercury battery installed) indicates f/2 at 1/125, my Konica is indicating f/4. I know enough about battery differences to think that this may be attributable to the voltage difference. My question is: is this sort of difference in meter readings "normal" when alkalines are installed? Is this the sort of difference you would expect to see? Do you think that switching to 1.35v mercury cells will bring the readings in line with my other meters, or does this sound like a problem that will require a meter recalibration? Thanks in advance for taking the time and trouble to help out a newcomer. Best regards, Jon Hechtman

-- Anonymous, February 24, 2001

Answers

Hi Jon

Your supposition is correct - the difference in voltage would give you a 1 to 1/12 stop difference in readings. This is evident in a T3 that I have with alkalines and my T2 with mercury (also shown using my Gossen Luna Pro F). Actually when using print film given the latitude of the film and the "accuracy" of most photofinishers, you probably won't notice much difference! If you use slides or do your own developing and printing you WILL notice a difference. If you need a contact to get mercury battteries, read a few messages before this one in the archives or send me a private emil.

Lee

-- Anonymous, February 24, 2001


Mercury Battery

Hi Jon,

As already mentioned, yes, correct voltage battery should correct that meter reading, at least I'd try that first, before recalibrating.

Mercury batteries can be hard to find, and expensive when you do (not to mention illegal in the US & ecologically incorrect)...

I believe your camera used 675s, if so you might want to try commonly available hearing aid Zinc Air batteries. These are 1.35V or 1.4V and work fine. They come in packs of 4 or more, usually, and are quite cheap. They store well (as long as they are sealed) so I keep a few on hand. You remove the seal just before installing and they come up to full power in an hour or two.

They don't last as long as mercury batteries, I've found 3 to 6 months in my T4s, but do hold a level voltage for most of their life (unlike alkalines, which gradually lose voltage, making meter re-calibrating tricky).

I've found my meter & AE are highly accurate with Zinc Airs and shoot a lot of slide film which is less forgiving of errors. Be sure to check the camera meter against another meter each time before you start shooting, as these batteries crash suddenly at the end of their life, with little warning.

The 675s can be adapted to use in place of 625s (as in T4s), with an o-ring, see other folks notes on this B.B.

Alan Myers San Jose, Calif.

-- Anonymous, February 26, 2001


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