Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 70,295   Posts: 1,535,634   Online: 1113
      
Page 1 of 4 1234 LastLast
Results 1 to 10 of 31
  1. #1

    Join Date
    Sep 2007
    Location
    Toronto Ontario Canada
    Shooter
    Med. Format Pan
    Posts
    335

    light meter battery for a Pentax Spotmatic II

    Does anyone know what type of battery powers the light meter in a Pentax Spotmatic II and where I can get one?

    Thanks,

    Doug

  2. #2
    BradS's Avatar
    Join Date
    Sep 2004
    Location
    S.F. Bay Area, California
    Shooter
    Large Format
    Posts
    4,008
    they originally used a mercury 1.35volt PX400 cell.

  3. #3
    Rol_Lei Nut's Avatar
    Join Date
    Jul 2006
    Location
    Hamburg
    Shooter
    Multi Format
    Posts
    1,118
    Since their meters are relatively insensitive to voltage differences, you can basically use any battery in the 1.3-1.5 range which fits, including alkaline cells.

    Mine currently contains a LR936 watch battery, with a rubber ring on it so that it fits better.
    M6, SL, SL2, R5, P6x7, SL3003, SL35-E, F, F2, FM, FE-2, Varex IIa

  4. #4
    David Brown's Avatar
    Join Date
    Feb 2004
    Location
    near Dallas, TX USA
    Shooter
    Medium Format
    Posts
    3,284
    Images
    6
    Google "Spotmatic battery" (or even search apug) and you'll get bunch of info.

  5. #5
    Anscojohn's Avatar
    Join Date
    Dec 2006
    Shooter
    Medium Format
    Posts
    2,727
    Images
    13
    Quote Originally Posted by spoolman View Post
    Does anyone know what type of battery powers the light meter in a Pentax Spotmatic II and where I can get one?

    Thanks,

    Doug
    I found this on another website. I did not know this. And I have a Spot II and did not know this.

    Quote on:
    Availability of batteries for the Spotmatic is better than other cameras of the era because the Asahi engineers built in a bridge circuit in the metering which makes it battery voltage independent. This means you can use the original 1.35 mercury PX400 battery, or a 1.5V silver-oxide replacement without problems. An exact fit PX400S is available, or you can use a #392 cell with a small rubber-O ring (purchasable at any fine home repair center or DIY store) as a spacer. I believe a #397 also fits as well.
    Quote off
    John, Mount Vernon, Virginia USA

  6. #6
    altair's Avatar
    Join Date
    Mar 2009
    Location
    Kuala Lumpur, Malaysia
    Shooter
    Multi Format
    Posts
    392
    I have an SP500,and like u,i was stumped about the battery too.tried alkaline LR54 cells,but it made the needle of my sp500 work backwards,how's that for weird.then i tried silver oxide cells,Maxell SR936SW,and it worked fine.try it.

  7. #7
    Steve Smith's Avatar
    Join Date
    May 2006
    Location
    Ryde, Isle of Wight
    Shooter
    Medium Format
    Posts
    8,591
    Images
    122
    As posted above, the Spotmatic is a bridge circuit which is fairly independant of actual voltage.

    This is because a bridge circuit works with a centre zero meter and correct exposure is obtained at that centre point. This is the point where no current is flowing through the meter, therefore the voltage is irrelevant.

    However, the Spotmatic circuit is offset slightly so the correct exposure reading is slightly off of centre with a small amount of current flow. This was done (I think) to enable the battery check function to work).

    What this means is that the Spotmatic circuit is slightly voltage dependant but not by enough to worry about in normal use.

    In practice, any 1.5v cell which fits and connects o.k. should work. I too have an SP500 and I have had some perfectly exposed transparencies from it using a 1.5v alkaline cell.


    Steve.
    "People who say things won't work are a dime a dozen. People who figure out how to make things work are worth a fortune" - Dave Rat.

  8. #8

    Join Date
    Nov 2009
    Location
    Bari - East Southern Italy
    Shooter
    35mm RF
    Posts
    71
    In my Pentax Spotmatic II i use a Varta 392 silver oxide battery (1,55 volt), with a proper blue ring of the original PX400, to block the battery in the compartment. If you don't have the blue ring, use a proper circular black O-ring. The internal circuit of the all Spotmatics work very well with mercury oxide PX400 1,35 volt and with Varta 392 silver oxide battery, without any problem.
    Ciao.
    Vincenzo

  9. #9

    Join Date
    Jun 2010
    Shooter
    35mm
    Posts
    128
    I've used a 387S watch battery in my SP1 and it fits well and seems to work okay.

  10. #10

    Join Date
    Mar 2009
    Shooter
    Multi Format
    Posts
    580
    Try LR43

Page 1 of 4 1234 LastLast


 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



Contact Us  |  Support Us!  |  Advertise  |  Site Terms  |  Archive  —   Search  |  Mobile Device Access  |  RSS  |  Facebook  |  Linkedin