Flash bulb Guide Number: clear Nr. 11

Discussion in 'Lighting' started by BrianShaw, Jun 20, 2011.

  1. BrianShaw

    BrianShaw Member

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    Does anyone happen to recall the guide number for the clear number 11 flash bulb?
     
  2. mopar_guy

    mopar_guy Subscriber

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    No. However, I have a few cases of Sylvania Press 40 bulbs. The Press 40 is very close to a #11. For the press 40, the packaging suggests the following guide numbers:

    Exposure Index 80-125 ASA (tungsten); up to 1/50 sec. = GN 300; 1/100 sec = GN 230; 1/200 sec = GN 180
     
  3. BrianShaw

    BrianShaw Member

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    Thanks, Dave.​
     
  4. brianmquinn

    brianmquinn Member

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    See post #45 under
    Flash Bulb Question P25 and #5 vs M25 and M5 or later M3
    There is a link to info on most GE Flashbulbs.
     
  5. BrianShaw

    BrianShaw Member

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    Thanks. I recall that interesting thread. I vaguely recall checking out the links in that thread but don't think I ever really got the exact answer I was looking for, though. I seem to recall all of those references were for blue tinted bulbs, and there is differing information on whether clear is 1 stop of .5 stop brighter than a blue bulb. I also didn't know at that time that Nr. 40 was essentially the same as the Nr. 11 until Dave mentioned it.

    This morning I found some other interesting reference materials at www.donsbulbs.com. That site has old sales brochures for all sorts of bulbs, including flashbulbs. Much of the data is expressed in terms of peak lumen rather than GN, but the Kodak Photoguide calculators can handle that type of data. In one brochure I found confirmation of waht I didn't know before: GE/Westinghouse Nr. 11 = Sylvania Press 40 = Photoflux PF38.
     
  6. BrianShaw

    BrianShaw Member

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    Correction to my last post:

    I must have stopped looking at that thread about post #44. The booklet from the Butkus site is EXACTLY waht I've been looking for. THANKS!