colyn
ישו משיח
Anybody know the size of the zinc air cell that is used in the MRB400 wein cell?
This is the replacement battery for the Pentax Spotmatic cameras in place of the original mercury cell..
This is the replacement battery for the Pentax Spotmatic cameras in place of the original mercury cell..
titrisol
Bottom Feeder
Why not use a normal silver oxide battery?
Spotmatics have a Wheatstone bridge type meter so the voltage difference makes no difference
I got the information a few years back from here: http://tech.groups.yahoo.com/group/Spotmatic/files/
but had been using silver cells since the 80s because they were cheaper and the pictures came out perfectly
After becoming more picky I have checked mine with a 392 cell against a Nikon FE and is well between 1/2 stop
Spotmatics have a Wheatstone bridge type meter so the voltage difference makes no difference
I got the information a few years back from here: http://tech.groups.yahoo.com/group/Spotmatic/files/
but had been using silver cells since the 80s because they were cheaper and the pictures came out perfectly
After becoming more picky I have checked mine with a 392 cell against a Nikon FE and is well between 1/2 stop
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kuzano
Veteran
They should...
They should...
The packaging on the MRB400 lists five Spotmatics served by that battery.
I get about a year out of Wein Cells (different number) for my Olympus OM-1. Part of increasing the life span is to take the battery out of the camera when not using it for extended periods and taping the air hole shut to stop the chemical reaction.
They should...
The packaging on the MRB400 lists five Spotmatics served by that battery.
I get about a year out of Wein Cells (different number) for my Olympus OM-1. Part of increasing the life span is to take the battery out of the camera when not using it for extended periods and taping the air hole shut to stop the chemical reaction.
colyn
ישו משיח
I tried this but got over a stop difference in exposure. The camera is accurate with the wein cell. Since I have the plastic wein cell spacer I'd like to buy the packages of zinc-air cells for easy replacement when one goes dead.
This has been proven to be false in some cases. My OM-1 is off with silver cells unless I use the adapter with the Schottky diode to reduce voltage.
A full stop off on exposure won't in most cases affect the outcome when using negative film but will affect proper slide film exposure..
colyn
ישו משיח
Most of the Spotmatics use the MRB400. The Spotmatic F uses silver cells.
What I want to do is buy the package of zinc-air cells so when one dies I can replace it with a new one...not a new wein cell. I need to know which size zinc-air cell was used in the wein cell..
newspaperguy
Well-known
colyn -
Your OM-1 does NOT have a Wheatstone bridge-type meter. As you've seen, it will not compensate for the higher voltage.
Like you said, the adapter, or have John H. rewire it. I did, and gave away my W-cell. I think it used the hearing aid size... came five to a card.
Your OM-1 does NOT have a Wheatstone bridge-type meter. As you've seen, it will not compensate for the higher voltage.
Like you said, the adapter, or have John H. rewire it. I did, and gave away my W-cell. I think it used the hearing aid size... came five to a card.