I need to confess: I regularly shoot canon.

jimH · 08-20-2009, 04:55 PM

Originally posted by MJB DIGITAL

Yeah I love my Canonet, too.

Hey, I read on wiki or camerapedia that if you get a different battery than the original your exposures might be off.

Any input?

Hey, just now wondered....Pentax Rangefinder?

I'm guessing that if the voltage is the same the camera won't care.

pingflood · 08-20-2009, 05:59 PM

Originally posted by MJB DIGITAL

Yeah I love my Canonet, too.

Hey, I read on wiki or camerapedia that if you get a different battery than the original your exposures might be off.

Any input?

Hey, just now wondered....Pentax Rangefinder?

It depends on the camera -- some have bridge / dual coil circuitry that makes it a little less voltage dependent. The Canonets I think all need the proper voltage to meter right. What the old mercury batteries did was twofold: the 1.35v output, and voltage that remained stable until the end of its life. Many modern batteries start off at say 1.5v and then taper down as they get older, so even if you manage to figure out how to compensate for the voltage difference it won't remain consistent.

The CRIS adapters are good but kind of costly -- weigh the cost of the Wein cells against that, based on expected life of the Weins and how long you plan to keep the camera. Figure on a Wein zinc-air lasting you 3-6 months in that thing.

Me, I would buy one zinc-air battery, make sure everything's working well and that you really want to use the meter, then consider getting the adapter.

Blue · 08-20-2009, 06:53 PM

That's ok MJB, I have a Ricoh Five One Nine and and Argus C4 rangefinder. They work also. The Ricoh doesn't even have a meter but it has a hot shoe.

Edit: When you lay your hands on that early SV, you are going to be a goner.

J.Scott · 08-20-2009, 07:26 PM

Use it guilt-free, my friend! I too have a canonet GIII QL.
I took mine apart and replaced the light seals then re-skinned it in beautiful dark green, fine grained leather. The air zinc 625 cells work perfectly. The meter on the camera matches my Sekonic light meter. I was fortunate that my Canonet came with a leather (like) case, strap and the working (matching) flash unit. It takes great pictures, too!

There is a great write up here.

er1kksen · 09-07-2009, 05:01 PM

Originally posted by MJB DIGITAL

Yeah I love my Canonet, too.

Hey, I read on wiki or camerapedia that if you get a different battery than the original your exposures might be off.

Any input?

Hey, just now wondered....Pentax Rangefinder?

On my old Olympus OM-1, there was a similar problem with the discontinued battery type (plus the meter cell was getting worn out), so the exposures were indeed off.

The solution? Take a camera whose meter you trust (try to have a similar focal length), and point it at a blank white wall. Take a meter reading, then compare it to what the Canonet meters from the same wall.

In the case of my OM-1, it turned out I needed to set the film speed to 25 to get accurate metering for ISO 100 film, and set the film speed to 100 to get accurate metering for ISO 400 film. Once you've determined how much you need to compensate the set film speed by, the metering differences really aren't a problem.

pingflood · 09-07-2009, 05:34 PM

Originally posted by er1kksen

On my old Olympus OM-1, there was a similar problem with the discontinued battery type (plus the meter cell was getting worn out), so the exposures were indeed off.

The solution? Take a camera whose meter you trust (try to have a similar focal length), and point it at a blank white wall. Take a meter reading, then compare it to what the Canonet meters from the same wall.

In the case of my OM-1, it turned out I needed to set the film speed to 25 to get accurate metering for ISO 100 film, and set the film speed to 100 to get accurate metering for ISO 400 film. Once you've determined how much you need to compensate the set film speed by, the metering differences really aren't a problem.

As long as the voltage of the battery you are using remains steady. Some batteries have the voltage decline as they get older, and your meter will be off from where you "calibrated" it.

er1kksen · 09-07-2009, 06:39 PM

This is true as well. It's better than nothing, though.

jimH · 09-08-2009, 05:52 AM

I found the following information concerning the battery:

Type: Alkaline
Voltage: 1.5 V
Diameter: 15.6 mm
Height: 5.95 mm

Also known as: PX625 / PX13 / EPX625 / V625PX / MR09 / MR9 / H-D / HD / RPX625 / RM625 / KX625 / HD1560 / 1124MP / Mallory RM-625R / Eveready E625N / Burgess HG-625R / 4370 / 4371 / V13PX / EPX13 / V625PX / HD625 / PN625 / RM625 / 4625 / 625 / H1560 / HD-D / M01 / M20 / 8930

The MR9, PX13 and PX625 is is a discontinued Mercuric Oxide coin type cell that was commonly used in cameras and is now banned because of toxicity and environmental fears.

The original PX625 mercury cell produced 1.35V.

There are three possible mercury free replacements for this PX625, PX13 or MR9 cell:

* genuine Mercury cell, the PX625, PX13 or MR9 - but they are rare and hard to find.
* the equivalent alkaline cell, the LR9 or V625U.
* the equivalent silver oxide cell, the S625PX.
* the equivalent zinc air cell, the WeinCELL MRB625.
* a voltage reducing adapter, the MR-9 adapter and a silver oxide 386 cell

The least expensive PX625 replacement is the alkaline cell, the LR9 or V625U. They fit perfectly but, as with all alkaline cells the voltage is not stable, it drifts down from 1.5V towards 1.35V (the voltage of the original Mercury cell) and then lower still. If you use the cell in a camera that needs a steady reference voltage, as the voltage is not steady throughout the useful life of the cells, you need to constantly adjust how you compensate.

Because the S625PX silver oxide cell produces a steady 1.55V, you are able to compensate for the higher voltage by a fixed number of stops or by adjusting the ASA setting. There may be as many as two f-stops underexposure by a camera that uses 1.55v instead of the original 1.35v, but the compensation you require is constant.

Another PX625 replacement is a zinc air battery. The WeinCELL MRB625 is a custom zinc/air battery designed to replace banned mercury batteries. WeinCELLs deliver the same 1.35 V voltage and stability of output as did the mercury PX625 batteries so there is no need to adjust your exposure. The WeinCELL MRB625 batteries last much longer than hearing aid batteries, some times up to a year. To achieve this longer life, the MRB625 used a proprietary electrolyte and has only two small air holes, instead of the 7 larger holes found in standard hearing aid batteries.

Possibly the 'Rolls Royce' of replacements is the MR-9 adapter fitted with a silver oxide 386 cell. The MR-9 adapter is the shape and size of a PX625 cell, has a recess into which a 1.55V silver oxide 386 cell can be dropped and and contains voltage regulating electronics to drop the voltage to match the 1.35V of the original mercury cell. The MR-9 adapter is expensive, but it can be reused time and time again with inexpensive silver oxide 386 cells. Over time you may find the MR-9 adapter will actually save you money over the other options.

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08-20-2009, 04:55 PM	#16
jimH Veteran Member Join Date: Apr 2009 Location: South Central Nebraska - USA Photos: Gallery \| Albums Posts: 1,771	Originally posted by MJB DIGITAL Yeah I love my Canonet, too. Hey, I read on wiki or camerapedia that if you get a different battery than the original your exposures might be off. Any input? Hey, just now wondered....Pentax Rangefinder? I'm guessing that if the voltage is the same the camera won't care.

08-20-2009, 05:59 PM	#17
pingflood Veteran Member Join Date: Jun 2008 Location: Borås, Sweden Photos: Gallery Posts: 3,169	Originally posted by MJB DIGITAL Yeah I love my Canonet, too. Hey, I read on wiki or camerapedia that if you get a different battery than the original your exposures might be off. Any input? Hey, just now wondered....Pentax Rangefinder? It depends on the camera -- some have bridge / dual coil circuitry that makes it a little less voltage dependent. The Canonets I think all need the proper voltage to meter right. What the old mercury batteries did was twofold: the 1.35v output, and voltage that remained stable until the end of its life. Many modern batteries start off at say 1.5v and then taper down as they get older, so even if you manage to figure out how to compensate for the voltage difference it won't remain consistent. The CRIS adapters are good but kind of costly -- weigh the cost of the Wein cells against that, based on expected life of the Weins and how long you plan to keep the camera. Figure on a Wein zinc-air lasting you 3-6 months in that thing. Me, I would buy one zinc-air battery, make sure everything's working well and that you really want to use the meter, then consider getting the adapter.

08-20-2009, 06:53 PM	#18
Blue Moderator Site Supporter Join Date: Jun 2008 Location: Florida Hill Country Photos: Gallery \| Albums Posts: 17,377	That's ok MJB, I have a Ricoh Five One Nine and and Argus C4 rangefinder. They work also. The Ricoh doesn't even have a meter but it has a hot shoe. Edit: When you lay your hands on that early SV, you are going to be a goner.

08-20-2009, 07:26 PM	#19
J.Scott Inactive Account Join Date: Mar 2007 Photos: Gallery Posts: 3,675	Use it guilt-free, my friend! I too have a canonet GIII QL. I took mine apart and replaced the light seals then re-skinned it in beautiful dark green, fine grained leather. The air zinc 625 cells work perfectly. The meter on the camera matches my Sekonic light meter. I was fortunate that my Canonet came with a leather (like) case, strap and the working (matching) flash unit. It takes great pictures, too! There is a great write up here.

09-07-2009, 05:01 PM	#20
er1kksen Veteran Member Join Date: Oct 2008 Location: Forestville, NY Photos: Albums Posts: 1,801	Originally posted by MJB DIGITAL Yeah I love my Canonet, too. Hey, I read on wiki or camerapedia that if you get a different battery than the original your exposures might be off. Any input? Hey, just now wondered....Pentax Rangefinder? On my old Olympus OM-1, there was a similar problem with the discontinued battery type (plus the meter cell was getting worn out), so the exposures were indeed off. The solution? Take a camera whose meter you trust (try to have a similar focal length), and point it at a blank white wall. Take a meter reading, then compare it to what the Canonet meters from the same wall. In the case of my OM-1, it turned out I needed to set the film speed to 25 to get accurate metering for ISO 100 film, and set the film speed to 100 to get accurate metering for ISO 400 film. Once you've determined how much you need to compensate the set film speed by, the metering differences really aren't a problem.

09-07-2009, 05:34 PM	#21
pingflood Veteran Member Join Date: Jun 2008 Location: Borås, Sweden Photos: Gallery Posts: 3,169	Originally posted by er1kksen On my old Olympus OM-1, there was a similar problem with the discontinued battery type (plus the meter cell was getting worn out), so the exposures were indeed off. The solution? Take a camera whose meter you trust (try to have a similar focal length), and point it at a blank white wall. Take a meter reading, then compare it to what the Canonet meters from the same wall. In the case of my OM-1, it turned out I needed to set the film speed to 25 to get accurate metering for ISO 100 film, and set the film speed to 100 to get accurate metering for ISO 400 film. Once you've determined how much you need to compensate the set film speed by, the metering differences really aren't a problem. As long as the voltage of the battery you are using remains steady. Some batteries have the voltage decline as they get older, and your meter will be off from where you "calibrated" it.

09-07-2009, 06:39 PM	#22
er1kksen Veteran Member Join Date: Oct 2008 Location: Forestville, NY Photos: Albums Posts: 1,801	This is true as well. It's better than nothing, though.

09-08-2009, 05:52 AM	#23
jimH Veteran Member Join Date: Apr 2009 Location: South Central Nebraska - USA Photos: Gallery \| Albums Posts: 1,771	I found the following information concerning the battery: Type: Alkaline Voltage: 1.5 V Diameter: 15.6 mm Height: 5.95 mm Also known as: PX625 / PX13 / EPX625 / V625PX / MR09 / MR9 / H-D / HD / RPX625 / RM625 / KX625 / HD1560 / 1124MP / Mallory RM-625R / Eveready E625N / Burgess HG-625R / 4370 / 4371 / V13PX / EPX13 / V625PX / HD625 / PN625 / RM625 / 4625 / 625 / H1560 / HD-D / M01 / M20 / 8930 The MR9, PX13 and PX625 is is a discontinued Mercuric Oxide coin type cell that was commonly used in cameras and is now banned because of toxicity and environmental fears. The original PX625 mercury cell produced 1.35V. There are three possible mercury free replacements for this PX625, PX13 or MR9 cell: * genuine Mercury cell, the PX625, PX13 or MR9 - but they are rare and hard to find. * the equivalent alkaline cell, the LR9 or V625U. * the equivalent silver oxide cell, the S625PX. * the equivalent zinc air cell, the WeinCELL MRB625. * a voltage reducing adapter, the MR-9 adapter and a silver oxide 386 cell The least expensive PX625 replacement is the alkaline cell, the LR9 or V625U. They fit perfectly but, as with all alkaline cells the voltage is not stable, it drifts down from 1.5V towards 1.35V (the voltage of the original Mercury cell) and then lower still. If you use the cell in a camera that needs a steady reference voltage, as the voltage is not steady throughout the useful life of the cells, you need to constantly adjust how you compensate. Because the S625PX silver oxide cell produces a steady 1.55V, you are able to compensate for the higher voltage by a fixed number of stops or by adjusting the ASA setting. There may be as many as two f-stops underexposure by a camera that uses 1.55v instead of the original 1.35v, but the compensation you require is constant. Another PX625 replacement is a zinc air battery. The WeinCELL MRB625 is a custom zinc/air battery designed to replace banned mercury batteries. WeinCELLs deliver the same 1.35 V voltage and stability of output as did the mercury PX625 batteries so there is no need to adjust your exposure. The WeinCELL MRB625 batteries last much longer than hearing aid batteries, some times up to a year. To achieve this longer life, the MRB625 used a proprietary electrolyte and has only two small air holes, instead of the 7 larger holes found in standard hearing aid batteries. Possibly the 'Rolls Royce' of replacements is the MR-9 adapter fitted with a silver oxide 386 cell. The MR-9 adapter is the shape and size of a PX625 cell, has a recess into which a 1.55V silver oxide 386 cell can be dropped and and contains voltage regulating electronics to drop the voltage to match the 1.35V of the original mercury cell. The MR-9 adapter is expensive, but it can be reused time and time again with inexpensive silver oxide 386 cells. Over time you may find the MR-9 adapter will actually save you money over the other options.