Luna-Pro battery help?

Discussion in 'Camera Building, Repairs & Modification' started by athanasius80, Aug 2, 2006.

  1. athanasius80

    athanasius80 Member

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    Hey guys,
    I just bought a Luna-Pro from a fellow APUGer and was recommended that I could use hearing aid batteries in lieu of Wein Cells. I've popped hearing aid batteries in, and the battery check comes up to half of what it should be.
    Any suggestions?
    Thanks,
    Chris
     
  2. rosey

    rosey Member

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    I have two Luna Pro meters. For one of them I actually have a couple still-good original mercury batteries. For the other, I Googled the Luna Pro distributor a few years ago and bought an adapter (in the $20 range) that used the MS76 or SR44 batteries. That Luna Pro reads exactly like the one with the 625 mercury cells.
    Are you using hearing aid batteries WITHOUT the adapter designed for them? If so, that's likely the problem.
    Rosey
     
  3. Dan Fromm

    Dan Fromm Member

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    Rosey, the hearing aid batteries are zinc-air types, their voltage is close enough to 1.35v for them to replace mercuries and they have the same nice nearly constant voltage until they die. I use 'em in my Minolta Flash Meter (original model, no #), and the only problem is that they don't last long.

    Chris, I did have problems with hearing aid batteries, though, the 675s I bought are a bit small and had to be wrapped with stuff so they'd stay in place and make good contact. In addition, they take some time to come up to voltage after their seals are removed. Try again.

    FWIW, a similar question came up yesterday. The current price of the adapter for using a pair of SR44s in a LunaPro is around $38. I think that C.R.I.S.' price for their adapter that holds a single SR44 and is the same size as a 625 is $30. Get the good 'un and don't look back. I use one in my LunaPro and it works well.

    Cheers,

    Dan
     
  4. Paul Sorensen

    Paul Sorensen Member

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    Hey there Chris,

    I did use hearing aid batteries, but I used the spacers that came with Wein batteries. I really don't know if that might be making the difference you are experiencing, or if it might be somehing else.
     
  5. BrianShaw

    BrianShaw Member

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    I, too, got the Gossen adapter (from B&H). It's epensive but the cost only hurts once. I use my Luna Pro all the time and it is extremely accurate.
     
  6. polaski

    polaski Member

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    Ditto on the Gossen adapter. Google Gossen USA. My Luna Pro S is spot on.
     
  7. plummerl

    plummerl Subscriber

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    I'll third on the Gossen adapter from B&H. It is perfect.
     
  8. RJS

    RJS Member

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    Hi - I've been using Wein batteires for some time with no problems. Is there a difficulty with them? I see B&H is out of the Gossen adapter, but at $40 why not use Wein batteries?
     
  9. Dan Fromm

    Dan Fromm Member

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    One-time capital outlay vs. never-ending operating expense. At $9.00 plus postage a pair from B&H, it doesn't take that long before Wein cells cost more. That's why.

    I note that B&H's price today for Wein cells and fixed price auctions on eBay are all well below what Wein cells used to go for. Interesting, any ideas what happened to force the price down?
     
  10. BrianShaw

    BrianShaw Member

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    I'll "fourth" this recommendation. It only hurts the first time you pay the price!
     
  11. Gerald Koch

    Gerald Koch Member

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    It takes anywhere from 30 minutes to an hour for zinc air batteries to come up to full voltage after being unsealed. Also make sure that the air holes are not being covered in any way by either another battery or the cover. They must have unrestricted air access. For certain devices a small hole must be made in the battery compartment cover to provide enough air.