My CL meter needs to be re-calibrated (based on telephone troubleshooting with DAG). I can choose to have the meter calibrated for a particular batery type. Having read the threads on alkaline versus Wein versus Cris adapters, is there a significant advantage of one over the other?

-- John Sonewald (jsonewald@aol.com), August 14, 2001

Answers

Alkaline cells are not optimal for this application. They change power curve characteristic over their lifespan which makes metering unreliable.

The Wein and CRIS adapter plus silver oxide cell give you the same power curve and characteristics as the original PX625 mercury cell. The CRIS adapter is a one time $30 expense, then it's normal battery consumption of easily available S76 silver oxide cells. The Wein cells work well but are not as long lived and are a bit expensive each.

I've gone with CRIS adapters in my equipment that needs them. They work very well.

-- Godfrey (ramarren@bayarea.net), August 14, 2001.

I'd have the camera calibrated for the new 1.5V Silver Oxide cells now available in the 625 size. You don't need to fool around with adapters. Look here for details on the batteries here http://www.photobattery.com/

-- Andrew Schank (aschank@flash.net), August 14, 2001.

Agreed. That would also give you the option of inserting an MS76 into the washer from a discarded Wein cell.

-- Jay (infinitydt@aol.com), August 14, 2001.

FWIW - Six months ago CRIS told me that their adapter will not fit in a CL. The adapter is too thick for the battery compartment.

-- Bob (robljones@home.com), August 14, 2001.

Too thick? It's .010" thicker than a PX625. Went right into my CL.

Godfrey

-- Godfrey (ramarren@bayarea.net), August 14, 2001.

If PX625 silver oxide cells are available and the meter can be calibrated to them, that would work well. I've not seen any of these batteries yet, though.

Godfrey

-- Godfrey (ramarren@bayarea.net), August 14, 2001.

This was recently posted to the Leica Customer Forum... "Leica Fotografie International carried an article about the Wein Cell on page 25 issue 5/2001. This zinc/air substitute for the discontinued mercury is supposed to be priced at about 8.2 Euro. The MRB624/1.35 as the Wein cell is catalogued is said to be even superior to the Old PX 625 mercuries with regards to its discharge properties. The article further stressed the possibility of galvanometer damage with the use of 1.5 V silver-oxide and warned against the use of a voltage adapter. Apparently, even though 1.35 volts is attained, errors in exposure readings are likely to happen due to the discharge characteristics of silver-oxide."

It appears that the silver-oxide suffers from the same problems as the Alkaline except that they last longer and take longer to change voltage.

-- Bud (budcook@attglobal.net), August 14, 2001.

If the output voltage is stepped down to 1.3v or the meter is recalibrated (not just by resetting the ASA)for 1.5v then there isn't any reason why the meter should suffer any damage. It is true that silver oxide batteries don't have quite as flat a discharge curve as Mercury or Zinc-air (Wein) cells, however the difference is quite small especially compared to Alkalines. Note that they do not recommend alkalines for the M6 yet silver oxide is fine.

-- Jay (infinitydt@aol.com), August 14, 2001.

regards: mercury vs silver oxide with adapter

I've been running a test for the past 2-3 years on the MR-9 plus S76 cell compared to the PX625 mercury cell. I have one of each loaded in two different Rollei 35s. Both are still going strong, both still return *identical* readings, and when I switch the batteries between the cameras, again they make identical meter readings. That's good enough for me. :-)

The Wein cells work well, but again they are somewhat expensive due to lifespan. They are activated by exposure to atmosphere and the active agent is a gelatin. Relative humidity has an effect on their lifespan, when the gelatin dries up they are dead. When I tried one, it lasted 4 months and then was dead, and the designer told me this was expected because I live in a relatively dry area.

-- Godfrey (ramarren@bayarea.net), August 14, 2001.