Optical Slave Help

Discussion in 'Photography Equipment & Products' started by solrac8126, Jan 25, 2008.

  1. solrac8126

    solrac8126 TPF Noob!

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    Hey i have one of those optical slaves
    The one i have it looks exactly like that one, is not the brand or the price but is the same one.
    Now, there is some sync problem with mine, When i fire it it fires 99% of the times BUT the flash will not sync with the camera...

    It happens some times even indoors, without any light and as closed or far as it can gets, i can see the flash firing but is not on the picture.
    I've tried all shutter speeds, but i don't think is a matter of speed cuz it does it sometimes only, and no matter the speed.

    Is this normal?
     
  2. Big Mike

    Big Mike I am Big, I am Mike Staff Member Supporting Member

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    The problem is the flash on your camera. Canon uses E-TTL for flash metering. This means that it fires a pre-flash, then uses the reflected light to determine how much power to use, then fires the flash again, this time with the shutter open. It all happens very fast, it's hard to notice.

    The problem is that the pre-flash triggers the optical slave, and the the flash can't fire again so quickly.

    Also, in case you are trying to trigger the 430EX with the slave...Canon flash units are known for not working very will with this type of thing.
     
  3. solrac8126

    solrac8126 TPF Noob!

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    i see so if i use the 430 on my cam but manually it should not be a problem then. is that right?
     
  4. Big Mike

    Big Mike I am Big, I am Mike Staff Member Supporting Member

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    yes, I think that would work.
     
  5. solrac8126

    solrac8126 TPF Noob!

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    IT DOES!!!!!
    ehehe thanx mike,
    actually the times i used the flash manually i did not had a second flash so i guess i'll try to use it manually when using a second flash.
     

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