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GeneW
08-09-2004, 06:26
Many of the older RF's as well as the Leica CL and Leica 5, used mercury 625 1.35V batteries now unavailable in NA and elsewhere due to environmental concerns.

What do you folks use to replace them? For my Olympus OM-1's I've been using Wein zinc-air batteries and get about 6 months service -- not bad. I've read about adapting hearing aid batteries, which are also zinc-air but cheaper than the Weins. And there's an adaper called, I think, MR-9, that takes silver oxide batteries and regulates the voltage to 1.35V.

My Leica CL still has a working meter and is still running strong on a mercury battery. But when it runs down, I'll need to replace it with something else.

I believe the Canonet GIII 17 and the Konica S3 have the same issue?

Gene

rover
08-09-2004, 06:39
I am a Wein guy. It is just easy for me, they can be found at Radio Shack and Ritz Camera locations.

Doug
08-09-2004, 12:40
Some cameras that use mercury batteries have a circuit that accomodates variations in battery voltage. Pentax Spotmatic is an example. These will run fine on modern silver cells that fit the battery compartment.

My old Gossen Super Pilot meter also is accurate with silver cells... not sure if it has the bridge circuit or if the camera repair guy was able to calibrate it.

I've been pretty lucky this way, so far. But the Olympus 35RC will someday need a new battery, then I'll have a decision to make. Already I've pulled the battery out of the Pen FT, and just use a separate meter.

Also, some cameras can be modified by adding a diode in the meter circuit to deal with the voltage difference, then they work fine with silver batteries. This would be my choice wherever possible, I think. I use zinc-air batteries in my hearing aids, and they're a royal pain, very short life.

bmattock
08-09-2004, 13:11
I think you hit on all the major things you can do, Gene. Personally, I tend not to rely on my built-in meters on vintage cameras and use an external meter. However, if you check the meter and it is close with a silver battery, you can try compensating by setting the film speed incorrectly (I forget if you set it higher or lower, dang).

If you are planning on using a vintage camera's meter for a long time, and you don't mind the expense, I'm told those converters work pretty well - plus, you can move it from camera to camera - I doubt if I'd buy one for EVERY camera!

Um, perhaps I should not say this - but I *have* seen the odd advert for the banned and outlawed mercury batteries. Just information for information's sake, you understand. I in no way condone that.

As mentioned, some of the older cameras DO compensate for voltage differences. I believe that the Yashica Electro series do. The Canonet, strangely enough, can be used with the adapter you mentioned, but the battery check light won't come on, although the meter will work. I am told that's because the current draw exceeds 200ma. Strange.

I have also heard of folks having their meters recalibrated by a camera repairman to use a silver cell - that might be the best long-term solution.

In the end, though - I seldom have that much faith in the built-in meters of older cameras, although often many of them are not bad. I tend to use an external meter with them.

Best Regards,

Bill Mattocks

JohnM
08-09-2004, 13:39
A few years back, I found a source of mercury batteries and I tried to stock up enough to carry me a s long as possible. So far, so good. The 625's are now all but impossible to find, even overseas, but there are still 675's to be found.

When they're spent, the local transfer station accepts them at no cost.

However, if I have a camera that is going in for a CLA, I just have it converted to silver oxide. Case in point, one of my Olympus RD's was converted last winter to the 1.5V silver oxide battery by John Hermanson - it's part of CamTech's standard overhaul/CLA and I think it's the most stable solution for battery replacement.

GeneW
08-09-2004, 15:35
Thanks everyone! Looks like I had the bases covered in terms of options. You'd think with so many 625 cams still operating it would be worth some battery manufacturer's time to make a 1.35v silver oxide. Ah well. I don't mind using Weins in my OM-1's cause they give me 6 months of reliable service and accurate metering. Less expensive than having the cameras recalibrated.

Gene

RichardS
08-09-2004, 15:53
You might check http://www.photobattery.com/
Type in the number of the original battery and it will show substitutes for it.

Dick

bmattock
08-09-2004, 16:33
Originally posted by RichardS
You might check http://www.photobattery.com/
Type in the number of the original battery and it will show substitutes for it.

Dick

Dick,

This is in no way to put you down, but there is a difference and 'acceptable substitutes' aren't really that at all.

You see, the original batteries used by most of these cameras was based on mercury and put out about 1.35 volts. Mercury batteries were good for camera meters, because they maintained their voltage for a very long time before they died - and then they died suddenly - no 'guessing' if the battery was really good or not. With me so far?

Mercury, it turns out, is bad for the environment if it gets loose in landfills and leeches into groundwater. Most governments on earth decided to ban the use of mercury in things like camera batteries for that reason.

The 'acceptable substitute' that one would get from your charts is either an alkaline 1.5 volt battery or a silver-oxide 1.5 volt battery. Both are NOT acceptable substitutes, because although they fit, they are the wrong voltage - off by just enough to throw the exposure of the camera off. And worse (for alkalines), it does not even throw them off by a predictable amount - they are all over the place. Still with me?

As it turns out, alkaline batteries start out well ABOVE the rated 1.5 volts (and even that is too high), and then drops pretty quickly. It does not have a nice level output until it dies, instead it drops and drops and drops until it is finally dead - but it may 'fool' you by lighting up your 'battery check' light until it is putting out way below what will work for your camera.

Silver oxide is a pretty stable battery - not as stable as mercury, but more stable than alkaline. But it too has a slope as it ages, and it too throws the meter off. However, many folks can compensate for the problems of silver oxide by setting the film speed intentionally wrong - just enough to compensate for the meter being off the other way. Make sense? Like throwing a ball in the wind - you aim to compensate for the wind factor.

There are also 'zinc' batteries, which work by reacting to ordinary air (therefore, they have little holes in them, and you activate them by peeling off some kind of covering over the air holes). These are often used in hearing aid batteries, among other things. They DO put out the right voltage - 1.25 volts. But depending on where you live, they die rather quickly and they cost quite a bit. Some folks use actual hearing-aid batteries with various adapters to make them physically fit in the camera, and those tend to be a bit cheaper.

You can also pay a camera repair person to recalibrate your meter to react more-or-less correctly with a silver oxide battery. Probably the best solution long-term, but even that is not perfect - the silver oxide, as mentioned, has a better 'glide slope' than the alkalines, but not as stable as the mercury - so it will go bad slowly, and leave you thinking it might be good still. You have to get used to changing batteries regularly, even if you think they are still good.

Finally, you can use an external meter, which is often the best solution - but not all older cameras will function at all without a meter in the camera and working - such as the Yashica Electro series.

So you see the dillemma. There is no easy solution, and you can't just look up the 'equivalent' battery online, because there isn't one, no matter what they say.

Of course, most modern color film has a 4-stop or tolerance, so you COULD get by with a modern replacement and no compensation in most cases - but most of us want the best performance possible from our older cameras, know what I mean?

Best Regards,

Bill Mattocks

PS - Welcome to RFF!!!

RichardS
08-10-2004, 13:52
Actually I've been here quite a while but for some reason my original username, DickS would no longer be recognized so I had to make a slight change in it.

And I have had no problem using the substitute batteries suggested at that web site in both cameras and exposure meters.

Dick

vladhed
09-18-2004, 15:04
So I did some battery experiments today, given that the Canonet QL17 came with a dead PX625 (having sat somewhere for a decade on "A"). I have the following:
- HD625 Hg battery from a Sekonics light meter I recently bought
- two 357 Ag2O batteries from my Nikon FE

The HD625 will squeeze into the Canonet and checks out with the battery test button (in the green area).

I found a plain wall where the Sekonic, the Nikon and the Canonet (with the Sekonic's battery) all agreed on exposure +/- 1/3 of a stop.

I put the 357 and a bit of aluminum foil into the Canonet and it measured the exposure as 2/3 of a stop brighter than it really is. Adjust the film speed setting accordingly, from 400 to 260, and it reads correctly.

So, although it contradits what I learnt in Chemistry, it appears that Hg = Ag2O + Al2O3 - 2/3 of a stop :D

Still, I guess the optimal solution is the Ag2O battery with a 1.25 volt Zener diode, since it will allow the battery to drop quite a bit in voltage before effecting exposure. Not sure what the discharge curve looks like but I suspect by the time a Ag2O battery gets to 1.25 volts it's dead dead dead.

lena.87
08-11-2007, 03:04
Hi
I've just bought a canonet G-III-QL17 and it needs a battery. Can anybody tell me what is best to buy? I have found a few on ebay, but i'm not sure whether they would be suited to the canonet. Would a zinc air battery 1.35v work alright?
Thanks, Lena

traveller
08-11-2007, 04:15
If you are able to do it yourself and need a manual or if you want to buy adapters, this is a good place to get some help

Adapter (http://www.buhla.de/Foto/batt-adapt-US.pdf)

clintock
08-11-2007, 06:59
For single-celled cameras like the canonet and the oly RC, the NTE 112 installed in series does the job.
http://www.nteinc.com/specs/100to199/pdf/nte112.pdf

A diode such as this is the active element in the MR9 adaptor.

For two-celled cameras like the Hi Matic E for example, a common silicone diode has about the right drop, such as 1n4001 for example..

photogdave
08-11-2007, 08:57
The Canadian importer for Wein has dropped the line. Any other Canadian sources?

Time Freeze
08-11-2007, 21:24
At work I received a new calculator ( the simple desk top type) and on the back is a warning that it contains mercury batteries and to dispose of it properly. If calculators can have mercury batteries why can't cameras? The calculator was distributed through Corporate Express and made in China (where else!).

John

lena.87
08-13-2007, 12:43
Thankyou for the replies, I'm still trying to decide which bat to go for. Not sure about the wein cell now that some say its not long lasting. But its either that or the MR-9 adapter with silver-oxide cell. Out of those two, does anyone have an idea which one would be better in the long run? and possibly where to find the best deal on those?

Lena

peterc
08-13-2007, 13:17
Any other Canadian sources?
Contact [email protected]
I think he still has a source.

venchka
08-13-2007, 13:44
Hi
I've just bought a canonet G-III-QL17 and it needs a battery. Can anybody tell me what is best to buy? I have found a few on ebay, but i'm not sure whether they would be suited to the canonet. Would a zinc air battery 1.35v work alright?
Thanks, Lena

About a month ago. I put a Wein zinc-air battery in it. It seems to be working fine. Maybe 1/2 stop overesposed. That could easily be in the camera and not the battery. If the second roll of film looks overexposed, I'll adjust the ASA setting accordingly on the camera. I'm using Wein cells in my Gossen Luna-Pro as well. Everything seems fine in both the meter & the Canonet.

PS: I've had a pair of Wein batteries in a Gossen Luna-Pro since last October or November. They are working fine. I'm also careful to switch the Canonet meter OFF when I'm not using it. Good luck.

spyder2000
08-13-2007, 13:57
Since the zinc cell is air activated, could one not cover the air holes when not in use and shut the battery down to save life? I haven't tried it, but has anyone else?

photogdave
08-13-2007, 14:12
Contact [email protected]
I think he still has a source.
Thanks Peter!

venchka
08-13-2007, 15:29
Since the zinc cell is air activated, could one not cover the air holes when not in use and shut the battery down to save life? I haven't tried it, but has anyone else?

...if you knew it would be out of service for awhile. I've also heard of folks covering all but one hole with clear nail polish.

I just make sure the camera's meter is off. I don't worry about the Gossen because it's always off until I take a reading.

climbing_vine
08-13-2007, 15:44
...if you knew it would be out of service for awhile. I've also heard of folks covering all but one whole with clear nail polish.

I just make sure the camera's meter is off. I don't worry about the Gossen because it's always off until I take a reading.

Turning it off can't hurt, but it won't help the usual early-expiry problem with zinc air, which is that they actually dry out inside. That's what covering the holes when not in use (or plugging all but one) is meant to prevent.

JNewell
08-13-2007, 16:09
I had a Wein in an M5 for a couple of years and it was still working when the camera went to Sherry K for CLA. Conversely, I tried regular hearing aid ZA cells in the Wein ring and they were NG, mostly because their voltage was in the 1.45-1.5 range and the meter simply didn't run right. The Wein cell had only two air holes, which may be why it ran longer...not sure why its running voltage was lower, unless that's also the holes, though I'd think that once it was activated it would run at whatever its spec'd voltage was.

photophorous
08-14-2007, 06:37
I compared the Wein 1.35 V zinc air battery directly to a drug store 675 1.4V hearing aid battery, and saw absolutely no difference in meter readings on my Canonet QL-17 GIII or a Yashica-MAT 124G. Physically, they are different in two ways. The Wein cell has a ring around it to make it larger in diameter. In the Canonet, this ring is not needed, but it is needed in the 124G. The other difference was in the number or air holes. The Wein cell had two air holes and the hearing aid batteries have four.

From this testing, I found no reason to buy more than one Wein cell. When it dies, you can pull the ring off of it and place it over a 675 hearing aid battery and get the same meter readings. The difference in air holes might cause the hearing aid battery to run down faster, but considering that they cost about 1/7 or 1/8 of what a Wein cell costs, I think it's still a good deal.

I don't use the Canonet too often, but when I do, I just check that the meter is working and make sure I have an extra battery.

Paul


ps...I just read JNewell's post above, so I guess my findings don't carry over to every camera. But, I think the hearing aid batteries are so cheap, it's woth buying some to make your own comparison.

Dr. Strangelove
08-14-2007, 06:58
Some cameras that use mercury batteries have a circuit that accomodates variations in battery voltage. Pentax Spotmatic is an example. These will run fine on modern silver cells that fit the battery compartment.

Also, some cameras can be modified by adding a diode in the meter circuit to deal with the voltage difference, then they work fine with silver batteries. This would be my choice wherever possible, I think. I use zinc-air batteries in my hearing aids, and they're a royal pain, very short life.
If a camera can use variable voltage cells, then even alkaline cells can be used. There is a direct alkaline replacement for the PX625. It is called PX625U or LR-9. Works at least in all Praktica LTL series SLR's, which use that battery size. It is readily available in Europe as it is made by Varta, but I have heard that it is more difficult to find in the US.

Which brand of zinc-air batteries you use, Doug? The Rayovac 675 (PR44) zinc-airs I use in cameras regularly last at least 3 months after activation and the average life is around 6 months. I have one that was activated in the beginning of December 2006 and it still works!

The zinc-airs are used in hearing aids since no other cell can provide the capacity of a zinc-air cell. The 675 for example has capacity of 630 mAh, which is four times the capacity of a similar sized silver-oxide cell (MS76 a.k.a SR44). So I suspect that your hearing aid zinc-air batteries might actually become depleted simply because hearing aids are used continuosly for long periods and they draw much more power than for example watches, but the zinc-airs might last a lot longer in other devices.

That said, I also know that the life after activation of zinc-airs does depend on the air intake design. The Wein cells are just zinc-air batteries with a single small air intake hole. Wein cell marketing material also says something about a "propietary oxidizer", but I am almost certain it is marketing bs -- after all, my Rayovacs last almost as long as the Wein cells...

Dr. Strangelove
08-14-2007, 07:19
Still, I guess the optimal solution is the Ag2O battery with a 1.25 volt Zener diode, since it will allow the battery to drop quite a bit in voltage before effecting exposure. Not sure what the discharge curve looks like but I suspect by the time a Ag2O battery gets to 1.25 volts it's dead dead dead.
Yes. The voltage curve of silver-oxide cells is similar to mercury, zinc-air and lithium cells. The voltage is initially about 1.6 V, then it will drop rapidly to about 1.55 V and after that the voltage will drop slowly to about 1.5 V, after which it will drop rapidly to below 1.2 V. Nominal cutoff voltage is usually listed at 1.2 V, but the drop from 1.5 to 1.2 is very rapid.

Dr. Strangelove
08-14-2007, 07:30
I had a Wein in an M5 for a couple of years and it was still working when the camera went to Sherry K for CLA. Conversely, I tried regular hearing aid ZA cells in the Wein ring and they were NG, mostly because their voltage was in the 1.45-1.5 range and the meter simply didn't run right. The Wein cell had only two air holes, which may be why it ran longer...not sure why its running voltage was lower, unless that's also the holes, though I'd think that once it was activated it would run at whatever its spec'd voltage was.
I find it very strange that a zinc-air cell would produce a voltage above 1.45 V. I have measured the voltage of a couple of them and it was always between 1.4 and 1.45 volts half an hour after activation. The Wine cells are just zinc-airs with smaller air intakes, so they should produce the same voltage as the hearing aid batteries. Here is the spec sheet of a Duracell zinc-air and for most part of the discharge curve the voltage is actually less than 1.3 volts:

http://www.duracell.com/oem/Pdf/new/ZA675_Dur.pdf

JNewell
08-14-2007, 09:46
I agree, but I had a whole pack of them that were all 1.45v or higher, and they gave the (expected) poor results in the M5. The Wein cells by comparison were all ~1.35v or a little over when checked.

I find it very strange that a zinc-air cell would produce a voltage above 1.45 V. I have measured the voltage of a couple of them and it was always between 1.4 and 1.45 volts half an hour after activation. The Wine cells are just zinc-airs with smaller air intakes, so they should produce the same voltage as the hearing aid batteries. Here is the spec sheet of a Duracell zinc-air and for most part of the discharge curve the voltage is actually less than 1.3 volts:

http://www.duracell.com/oem/Pdf/new/ZA675_Dur.pdf

lena.87
08-15-2007, 03:20
Does anyone know where I can get the best deal on an MR-9 adapter and cell, preferably in the UK?

Lena

traveller
08-15-2007, 03:55
The MR9-adapter costs about $ 30 w/o shipping from CrisCam (http://shop.criscam.com/product.php?productid=2&cat=1&page=1)

The ready made adapter from Fran de Gruijter (http://www.buhla.de/Foto/batt-adapt-US.pdf) costs 15 incl. shipping and works like a charm but you have ask first if it is in stock. And the Netherlands are not so far away :D

Bill58
08-15-2007, 06:32
Does anyone know where I can get the best deal on an MR-9 adapter and cell, preferably in the UK?

Lena

Maybe I caught them on a bad day, but the Criscam people were less than customer friendly, so I got all my adapters (MR-9, etc.) from the most helpful people at Kanto in Japan: http://www.kanto-cs.co.jp/english/index_english.html

I've used them and silver oxide batteries in all my cameras and have had zero problems.

Bill

payasam
08-15-2007, 06:58
I have adapters from Frans de Gruijter. They work perfectly. Google should bring up an address for him.

rxmd
08-15-2007, 07:28
There's a good article called "The mercury cell problem and its solutions", the PDF is linked at http://www.butkus.org/chinon/batt-adapt-us.pdf. It has comparisons of various batteries and their replacements, including discharge curves and circuit diagrams, as well as instructions for making various kinds of battery adapters. The author is aforementioned Frans de Gruijter, who is also selling some adapter DIY kits and readymade adapters.

Still, I guess the optimal solution is the Ag2O battery with a 1.25 volt Zener diode, since it will allow the battery to drop quite a bit in voltage before effecting exposure. Not sure what the discharge curve looks like but I suspect by the time a Ag2O battery gets to 1.25 volts it's dead dead dead.
And this is exactly the reason why using a Zener diode is a Bad Idea.

You are probably suggesting a circuit with the Zener diode parallel to the metering circuit (otherwise voltage stabilisation makes no sense) - the idea being that the Zener diode stabilises the voltage to 1.25 volts. That's indeed what it does, but it does so by burning away all the excess voltage. So your Zener diode will suck the battery empty and convert the excess voltage into heat, until the battery voltage has dropped to 1.25 V, at which point the battery is indeed dead dead dead for our purpose.

Philipp

JohnL
08-15-2007, 15:29
Does anyone know where I can get the best deal on an MR-9 adapter and cell, preferably in the UK?

Lena

John Neal, a member of this forum from the UK, used to make adapters for using silver cells to replace mercury cells. Not sure if he still does. HTH

charjohncarter
08-15-2007, 16:31
Most of my older cameras (except my Spotmatic) require 1.35 volts. I use the zinc air hearing aid batteries. They are slightly smaller in diameter, to rectify this I use a thin piece of form cut to fit (around). I tried the 'O' rings and the adapters this seems to work the best. Just be sure you carry them with you.

Jon Goodman
08-18-2007, 06:12
I don't know who came up with this idea originally, but I've made these adapters for my own use for years. Anyone who bought a Canonet from me probably found one in there. For a conversion from hearing aid (675) to PX-13 battery, they work great, and since each cell is vented, they're infinitely stackable. You can read about them here: http://nelsonfoto.com/v/showthread.php?t=11131 (scroll down a bit past the last image to see the final one with the foam spacer installed).
Jon

Xmas
08-18-2007, 06:44
There's a good article called "The mercury cell problem and its solutions", the PDF is linked at http://www.butkus.org/chinon/batt-adapt-us.pdf. It has comparisons of various batteries and their replacements, including discharge curves and circuit diagrams, as well as instructions for making various kinds of battery adapters. The author is aforementioned Frans de Gruijter, who is also selling some adapter DIY kits and readymade adapters.


And this is exactly the reason why using a Zener diode is a Bad Idea.

You are probably suggesting a circuit with the Zener diode parallel to the metering circuit (otherwise voltage stabilisation makes no sense) - the idea being that the Zener diode stabilises the voltage to 1.25 volts. That's indeed what it does, but it does so by burning away all the excess voltage. So your Zener diode will suck the battery empty and convert the excess voltage into heat, until the battery voltage has dropped to 1.25 V, at which point the battery is indeed dead dead dead for our purpose.

Philipp
The diode used is a Shockey diode, like in a crystal radio set, not a Zener, the diode is in series, and does not alter battery life, it drops the battery voltage.
Noel

Murray Kelly
08-18-2007, 09:23
Only for purposes of reference, I have a Rollei E-110 and the 5.6v mercury is replaceable with a newer siver 6v silver cell if one replaces the 'steering' diode which is germanium (not schottkey) with a silicon 1N914 signal doide or similar. It lives just outside the battery holder. The diode prevents damage with accidental placement of the battery round the wrong way.

The extra .4v voltage drop places the silver cell exactly in the range required for the E-110 metering to work perfectly.

It does require some skill in working with tiny parts but the new diode is smaller than the original and is working in the right current range when the shutter closes - an important point with diodes. The voltage drop of a sand state diode depends on the current at very low currents and apparently the electronics use enough to to get the required .4v drop for metering.

I am very happy with the E-110 now, and am getting great pleasure useing it.

Just an aside to the topic, but maybe useful to someone who has trouble with that camera and can't get mercury cells!

Murray

dll927
08-18-2007, 12:33
For what it's worth, I have an (older) Gossen N-100 hand-held meter that also originally used the 1.35 mercury batteries. Two, in fact. When I had to replace the batteries and the 1.35s were no longer available (thanks to another coup by the enviros), I e-mailed the Gossen company about it. The reply was that the Wein batteries were slightly higher voltage and might give a slightly higher reading (possibly leading to a bit of under-exposure). I used the meter for color slide film, so that could have been OK, since slide film likes slight under-exposure. But other than that matter, they said there was no reason not to use the Weins - in other words, no harm done to the meter.

sepiareverb
08-18-2007, 17:11
I had Sherry change my M5 to take the modern battery. Much simpler, but I won't recoup the cost in savings of battery costs. I do consider the headache factor worth it.

John Robertson
08-18-2007, 17:38
MR 9 + silver oxide 386
I have been using these for about five+ years in my Leica M5 and CL with no problems.
The Wein cells were a pain in the **** especially as the CL battery chamber is inside the camera.
http://criscam.com/products_services/mercury_battery_adapters/

lena.87
08-20-2007, 02:32
I ended up buying some zinc air cells. Put one in with a bit of foil and it seems to work fine. Just got to see how long they last.
Thanks for the advice
Lena