copladocus

another response to the actual question. Thank you!

copladocus

Good guess, but in this case, no cigar. Nothing at all....

bluezzzzz Loc: Stamping Ground, KY

Late to the party, as usual, but I dug out my old Lunasix 3 meter, and here is a pic of the battery position.

Great old-time meter, BTW!

copladocus

Perfect response to the question. Thanks!

amfoto1 Loc: San Jose, Calif. USA

Try to find a Gossen #4145 battery adapter. This is designed to hold two SR44 or two 357 or two 76 silver oxide batteries. Those are widely available and have a life span much closer to that of the original PX625 mercury batteries that meter used.

The #4145 adapter is no longer made, but can be found used sometimes. Keep watching for one on eBay and elsewhere. It not only hold the two batteries and fills up the battery compartment of the meter, it also corrects the voltage so that the meter will read correctly.

The Wein batteries you got are Zinc Air. Those will work okay, too. But they don't last long and end up being quite expensive. Taping up the holes won't lengthen their life. Once air is let inside, that activates the batteries and they will provide a level power output for maybe three or four months, then die quickly. Note that when you first remove the seal from the battery to let air inside, they will be slightly under powered. After about half an hour they'll come up the the correct power level and will remain steady.

The advantages of silver oxide is that they also have a steady power output, but a much longer life... one or two years is possible, depending upon the device. Also, they're sealed so removing them (or just turning the device off) will stop them from draining. Initially silver oxide are sometimes over powered, but settle down to a steady output after about half an hour. They'll maintain that for some time. In this case, the #4145 adapter should correct the voltage right from new.

DO NOT try to use 625 alkaline batteries (or any other type of alkaline, for that matter). They don't have a level power output and will give incorrect readings throughout their lifetime. There is no way to adjust for them either, since the voltage starts to drop right from new and simply continued to taper off. There are meters and cameras that can use alkaline batteries, but they have a voltage stabilizing circuit. Most meters and cameras that originally used mercury batteries do not have that circuit. (Alkaline batteries also are the type most prone to leak and do damage to electronic devices.)

If the Wein batteries you got have a metal ring pressed on, once they are run down remove that. You can buy 675 size hearing aid batteries very cheaply and simply install that metal ring on them to keep them centered inside the meter's battery compartment. For that matter, due to the way the two batteries stack in that meter, you also could just go to a hardware store and buy a few O rings in a size that fits snugly onto those hearing aid batteries and is large enough to keep them centered in the battery compartment without getting stuck in there.

You can use a similar trick with the silver oxide batteries, but still have the problem with the batteries having too high voltage. It might be possible to have the meter re-calibrated to use them. You'd have to check with a repair tech.

Wein 625 zinc air batteries cost around $4.50 each (at B&H) and if you're very lucky you will use six of them a year to power that meter. $27 annual cost.

675 zinc air hearing aid batteries can be bought on Amazon for $1 ea. (known brand) or even 50¢ ea. (unknown brand). They probably won't last as long as the Wein, so you might use 12 of them a year. $6 to $12 annual cost.

LR44 silver oxide batteries cost around $2 ea. (B&H) and will last at least a year. $2 annual cost.

Back when they were still being made, the Gossen #4145 adapter was a bit pricey at about $40, if memory serves. But it was a one time purchase and they typically came with a couple of the appropriate silver oxide batteries.

Gossen Luna Pro is an excellent meter, if you can make it work!

copladocus

Thanks for the advice. Yes, getting an adapter is going to be essential. I will not be using the meter much for my daily work but want it for my own artistic efforts I do from time to time.

therwol Loc: USA

You are referring to the Gossen Go 4145 adapter. It was made by Panasonic. I couldn't find one in a quick search, but that doesn't mean one can't be found.

The Gossen-made adapter was the V206A, also no longer made. I posted a photo of it earlier in this thread. I had one and gave it away to someone who needed it. The instructions say "Bogen", but it's the real deal. Bogen and Gossen had a business relationship at one point, and Bogen distributed Gossen products in the US.

flyboy61 Loc: The Great American Desert

I just checked my Lunasix 3 instructions. It has the voltage reduction adapter in it, and I got some Duracell LR 44 batteries, and installed them with the flat (Marked +) up. It seems to work just fine. It reads the same as my camera meter.
It zeems zat Churmann Engineers expekt all zose purchasink the Belichtung Messer VILL know how to install ze batteries correktly!
Battery Zero and Test work properly, but the battery position looks backwards from the tiny illustration above the battery compartment Cover. ??? Oh well, Nothing I did let out any of the magic smoke that lets the system work.