The LunaPro battery issue

firstdue

The short version; I bought an eBay Gossen LunaPro, newer model, but wasn't aware of the mercury battery issue, my test roll using px625 batteries was way underexposed by a couple stops at least. I bought the adapter to use 76/44 batteries but now it won't meter at all.

The long version; I've tried everything; cleaning the contacts (they looked clean to begin with), tried a different new set of 44s, put the adaptor cup in upside down, used a volt meter on the batteries. When the 625 batteries are in the meter, the battery meter reads low, like it should. When the adaptor is in the battery meter reads zero. :dunno

Totally at a loss to explain. The meter is clean and a newer version. I'll call B&H and Gossen/Bogen this week. I'm out of ideas.

ziggy53

Firstdue, welcome to the Digital Grin.

Your best bet is to use the WeinCell zinc-air batteries:

http://www.vintagebatteries.com/px625.htm

If you want to try to figure out what is wrong with your adapter and LR44 battery problems you should use a voltmeter to check for proper output voltage from the adapter and correct orientation to make sure you are not accidentally inserting in the wrong direction.

Art Scott

ziggy53 wrote:

Firstdue, welcome to the Digital Grin.

Your best bet is to use the WeinCell zinc-air batteries:

http://www.vintagebatteries.com/px625.htm

If you want to try to figure out what is wrong with your adapter and LR44 battery problems you should use a voltmeter to check for proper output voltage from the adapter and correct orientation to make sure you are not accidentally inserting in the wrong direction.

just might be the place to get batteries for my Pentax Spot Meter.....also...

Thanx ziggy53

firstdue

Thx for that ziggy and I hadn't realized I hadn't posted here before. I"ve lurked and read, but no t posted. I prefer to shoot rather than talk.

The last paragraph from that Wein cells is interesting:

An alternative mercury free replacement for the PX625 is the silver oxide S625PX. These S625PX cells produce 1.55V which is higher than the 1.35V produced by the original PX625 mercury cell. 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. I will be offering these Silver Oxide units later this month.

For my next test roll of print film maybe I'll use my DSLR alongside the Luna Pro with the silver oxide 625s I already have and see what the exact difference is (within the limits of a camera meter as opposed to the hand held.)

Although not a topic for this thread, my ultimate goal is to go back to film, probably medium format for my landscape stuff.

My SmugMug site is www.firstdueproductions.com