Flash bulbs with modern film cameras

Discussion in 'Modern Film Cameras' started by alan_rockwood, Aug 14, 2015.

  1. I am looking for information on using flash bulbs with modern film cameras. ("Flash bulbs" as in AG-1, 25B, M3B, etc., "not electronic flash".)
    I have several Canon Rebel-series cameras (ranging from Rebel 2000 to Rebel T2) and would appreciate any information on the feasibility of using flash bulbs with these cameras. I imagine the biggest issues would relate to the electronic sync., both respect to timing as well as voltage or current limitations.
    Thanks.
     
  2. Aren't there attachments for flash units that would be remotely triggered by the fill-in flash on the digital camera?
     
  3. Wow ... It's been many decades since I've thought about this ... Since flashbulbs operate by what amounts to a
    combusion process, it takes a significant amount of time (maybe 30-100 msec, I don't remember the exact number ...
    depends on the size of the bulb) for the bulb's light output to reach it's maximum light output once triggered. This means
    that one has to trigger the flash before the shutter is opened. This is the reason for the various synchronization options
    on old cameras. In contrast, electronic flashes fire almost instantly after triggering, so the shutter is opened first, then the
    (electronic) flash is fired.

    So, you would have to rig up some means of sequencing the events, or if the situation permits, you might be able to
    essentially paint with light by opening the shutter and firing the flash bulb(s) manually.

    Tom M
     
  4. http://petapixel.com/2013/01/16/using-a-vintage-
    disposable-bulb-flash-unit-with-a-new-digital-camera/
     
  5. New cameras lack the correct sync timing for flash bulb. For electronic flash the flash is fired when the shutter is fully open but for bulb, the flash has to be fired before the shutter open because it takes some time for the bulb to ignite and reach full brightness.
     
  6. The Petapixel link doesn't work
     
  7. regarding the Petapixel link, I found that if I use it in a google search I can find the page.
     
  8. There was a space in the aforementioned Petapixel link. Try this one. Sorry.
    http://petapixel.com/2013/01/16/using-a-vintage-disposable-bulb-flash-unit-with-a-new-digital-camera/
     
  9. With older cameras, it was somewhat usual to provide X (electronic flash) sync. on one shutter speed, and M (flashbulb) on others.
    With a slow enough shutter speed, it should work, with 1/30 about right. Smaller bulbs like AG-1 are pretty fast.
    For many years, I used flashcubes with an appropriate flashgun, on a rangefinder Canon and 1/30 s, with fine results. (I believe it does M sync, for that.)
    In the early years of flashbulbs, when films were slower, I believe it was usual to open the shutter, fire the flash, then close the shutter. Rooms were dark enough, and flashbulbs were bigger. (The size of today's incandescent lamps.)
    The flashcube flashgun I have needs a 5.6V battery, so not too much for modern electronic cameras. I don't know how much current cameras are designed to allow, though. As far as I know, the usual electronic film camera from the 1970's through 1990's has mechanical switch contacts, but some might do electronic switching.
    I have some to try with older film cameras. I hadn't thought to try them with newer cameras.
     
  10. More details in:
    http://www.photo.net/classic-cameras-forum/00CYlj
    seems to agree that with the faster bulbs, AG-1 or flashcubes, that X sync at 1/30 should work.
    I believe that M2 are a little faster than M3, both probably fine for X at 1/30, though you might not get all the light that you would with M sync.
    With #5 or #25, 1/15 with X sync would be good, but 1/30 would likely also work.
     
  11. Last time I used flash bulbs, especially AG-1 (in a Zeiss miniature flash unit with folding fan), the correct shutter speed was 1/25-1/30...I used a Contax IIA color dial....this was in the late sixties - 1967 or 1968.
     
  12. In my day, you piled flash powder into a tray, opened the shutter, covered your eyes and "POW!" That's why us old-timers wore wide-brimmed hats and canvas coats, even in summer. Mrs. O'Leary's cow had nothing to do with the Great Chicago Fire, it was a 19th century paparazza.
    Seriously, a little AG-1 bulb puts out as much light as a 400 Joule electronic flash. When Tri-X was rated 200, you needed something like that. At ISO 25,600, the LED on my cell phone would suffice. Most bulbs need to be fired 20 msec before the shutter opens to achieve full brilliance. If you shoot at 1/25 or slower, you can probably get by with zero delay. Clear bulbs used a different combustable (a paste), and needed only 5 msec advance.
    You should use something to isolate your flash shoe from the hot spark an old flash bulb requires.
    Buried in a cabinet in my old newspaper, along with and early Speed Graphic or two, was a small briefcase with flash powder cartridges and a spark gun. I should have popped one, just for fun, but never did. You could light up Time Square that way, or Mammoth Cave.
     
  13. The flash sync on a Leica film camera (M2, M3) is 1/50 sec. The flash sync speed is the MAXIMUM speed at which the shutter curtain will be open with the flash timed just right. Slower speeds are ok too. One thing that I just learned is that with flash, as long as you are at the sync speed or slower, what's really important is the aperture at which you are shooting at corresponds with the appropriate distance and guide number (GN) of the bulb you are using. Most bulbs have the chart on the back of the box. There are many resources on the Internet also. If anyone still cares I would be happy to post a couple relevant ones.
     
  14. For mechanical cameras, there is a switch contact somewhere triggered by the shutter motion.
    For electromechanical shutters, where an electromagnet releases a mechanical shutter, it could be the same, or it could be a transistor switch. In the latter case, there are polarity and voltage limitations. Many electronic flash units use hundreds of volts for triggering, directly through the sync connection.
    I have one flashgun with a 6 volt battery, so low enough for those Canon cameras with a 6V limit. Another one has a 22.5 volt battery. Many cameras are polarity sensitive, so check that.
     
  15. The Nikon N80:
    http://www.cameramanuals.org/nikon_pdf/nikon_n80_n80qd.pdf
    specifically says to only use Nikon flash units, as the voltage (250V or greater), electrical contact alignment, or switch phase might not be compatible. Not that I understand the last two.
    I believe that many Nikon DSLRs have a similar 250V limit, and that many others have a much lower limit.
     

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