Mercury Batteries : LUSENET : Canon FD : One Thread

Hello Fellow Canon Lovers! This is a great site. Just bought a Canon F-1n (3200 ASA) and am involved in finding the correct battery for the light meter. Original owner had a PX625A (1.5V) in the camera. I bought some "original" mercury batteries from two internet sources: and Got the first shipment today. Installed one of the mercury batteries and the metered exposure dropped 1.5 stops. However, the F-1's internal battery checker says the new mercury battery voltage is insufficient. Going to test on some slides today. Does anyone have experience with currently available 1.35V mercury batteries? The ones I got are not marked as to where made or dated for "freshness". Email with the seller says the batteries are fresh. I realize these batteries must be properly disposed of and will do that. I have researched most of the alternatives (cris adaptor and wein cell) and, due to performance characteristics, would like to keep using the "original" battery if possible. Thanks in advance for your time.


-- Don Boyd (, January 27, 2002


Hi Don I've seen various queries about F1N batteries and I must say I'm a little confused. Maybe things are a little different here in Europe, but I've no problem getting batteries. In the instructions it lists these options:

Lithium- Duracell PX28L Alkaline Manganese- LR44 Silver Oxide - SR44

All of these are very available here. If you can't get them in US try Jessops at They are the biggest dealer in UK and have all these cells.

Cheers Steve

-- Steve Phillipps (, January 28, 2002.

Oops, I've just looked again and realised it's an F-1n and not an F-1N, so its the new version of the old F-1! Boy it's confusing! I've just checked a few sites here in UK and I can't find a PX625a listed here either. Hmmm! If I do locate any I'll post it here. Good luck.


-- Steve Phillipps (, January 28, 2002.


I have the choices to make with a Canon FTbn. I opted for using the C.R.I.S. adaptor.

The exposure difference of 1.5 stops you observe seems consistent with what I have read about the offset that results when a 1.5 volt cell (alkaline or silver oxide) is substituted for the mercury cell. However, the battery check indication of low voltage is curious. Did you measure the voltage of the "new" mercury cell?

If it measures 1.35 volts and the battery check indicates low voltage, a possible explanation is that the former owner had the meter re-calibrated for use with 1.5 volt cells. If this is the case you can expect the meter reading to change as the alkaline or silver oxide cell voltage drops over time, unlike the original mercury cell.

Mike Naney

-- Mike Naney (, January 31, 2002.

I was under the impression that this problem had been solved. If there is still an unsatisfactory solution, one of the consultants I work with, has the capability of manufacturing batteries that could possibly solve this problem, but he would need to know the potential market in order to proceed. He's a Canon F1 photographer.


-- Dennis O. Larsen (, February 05, 2002.

Mike, As an inept D-I-Y guy, how could I get the output of a 1.35V mercury measured. Go to Radio Shack? Buy a battery meter? Seriously, I would like much to get my "new" mercury cells measured but don't know how. Suggestions?


-- Don (, February 14, 2002.

do a google search for mercury batteries. You will find several sources.

-- David Presson (, February 16, 2002.

Shipped my "new" F1n to Mr Oikawa for CLA and overhaul. He just called and stated the new 1.35V mercury battery I had in the camera (a Varta from Germany) tested spot on. He will fine tune my meters power sensitivity during the overhaul. Guess I'll keep the batteries I put in the fridge!! Thanks to all. Don

-- Don Boyd (, March 03, 2002.

Does anyone have any experience with the C.R.I.S adaptor? I'm considering buying one because it seems to be the best answer to the replacement problem. Any help would be appreciated.

-- Jim Costello (, March 04, 2002.

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