Results 1 to 9 of 9

Thread: High trigger voltage for external flash..... is it really harmful?

  1. #1
    Senior Member
    Join Date
    Jan 2002
    Location
    Singapore
    Posts
    12,938

    Default High trigger voltage for external flash..... is it really harmful?

    For cameras using PC Cord or Hot shoe to sync, is it really harmful if the trigger voltage is 200+V?

    I measured the resistance of the "socket" of my camera and found that it's open circuit normally and when it sends a trigger, the resistance is in the region of Mohms (I was using a multimeter and couldn't capture the exact changes in resistance).
    Check out my wildlife pics at www.instagram.com/conrad_nature

  2. #2
    Senior Member
    Join Date
    Jan 2002
    Location
    Singapore, Singapore, Singapor
    Posts
    6,405

    Default Re: High trigger voltage for external flash..... is it really harmful?

    Originally posted by mpenza
    For cameras using PC Cord or Hot shoe to sync, is it really harmful if the trigger voltage is 200+V?

    I measured the resistance of the "socket" of my camera and found that it's open circuit normally and when it sends a trigger, the resistance is in the region of Mohms (I was using a multimeter and couldn't capture the exact changes in resistance).
    Whether it's harmful will depend on individual camera's specs. For Nikon Coolpix series, the acceptable trigger voltage is about 200V. For Canon G1/G2, I read it's like 5V only. Using a flash with a trigger voltage > specified will result in damage to the camera's flash circuitry or the whole camera. Be careful.

    Resistance of the socket of the camera is not an accurate way to test. Most cameras use an electronic switch to trigger the flash, and the contact time is very, very short, so you can't really measure it. For mechanical cameras, a mechanical contact switch is used.

    Regards
    CK

  3. #3
    Senior Member
    Join Date
    Jan 2002
    Location
    Singapore
    Posts
    12,938

    Default

    Thanks. I'll see if I could find another way to test... if only I have an oscilloscope, I could measure the waveform with respect to time.
    Check out my wildlife pics at www.instagram.com/conrad_nature

  4. #4
    Senior Member
    Join Date
    Jan 2002
    Location
    Singapore, Singapore, Singapor
    Posts
    6,405

    Default

    Originally posted by mpenza
    Thanks. I'll see if I could find another way to test... if only I have an oscilloscope, I could measure the waveform with respect to time.
    Oh, trigger voltage is simple enough to test. Put the Multimeter to VOLT mode, turn on the flash and let it charge, then put the negative probe on the side contact of the hotshoe, and the positive probe to the centre pin.

    Regards
    CK

  5. #5
    Senior Member
    Join Date
    Jan 2002
    Location
    Singapore
    Posts
    12,938

    Default

    I got that.... reads ~240V. I just wanted to see if there's any way to test the characteriestics of the camera socket.
    Check out my wildlife pics at www.instagram.com/conrad_nature

  6. #6
    Senior Member
    Join Date
    Jan 2002
    Location
    Singapore, Singapore, Singapor
    Posts
    6,405

    Default

    Hi,

    Wah, that's very high. You might want to get the Wein Safe-Sync which will isolate the high trigger voltage from the camera. Not sure where it's available in Singapore though.

    Regards
    CK

  7. #7
    Senior Member
    Join Date
    Jan 2002
    Location
    Singapore
    Posts
    12,938

    Default

    I did see something like this in CathayPhoto. But the listed price is quite high... higher than my flash
    Check out my wildlife pics at www.instagram.com/conrad_nature

  8. #8
    Senior Member
    Join Date
    Jan 2002
    Location
    Singapore, Singapore, Singapor
    Posts
    6,405

    Default

    Originally posted by mpenza
    I did see something like this in CathayPhoto. But the listed price is quite high... higher than my flash
    How much? Alternatively, if you are an electronics hobbyist-type person, you can build one yourself too. I saw a couple of circuits for this on the net before. Just need an opto-coupler and some other small components.

    Regards
    CK

  9. #9
    Senior Member
    Join Date
    Jan 2002
    Location
    Singapore
    Posts
    12,938

    Default

    the listed price was $75 if I'm not wrong. will search for something thanks for your advice
    Check out my wildlife pics at www.instagram.com/conrad_nature

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •