Results 1 to 8 of 8

Thread: Slave flash questions

  1. #1

    Join Date
    Mar 2012
    Location
    United States
    Posts
    21
    Real Name
    William

    Slave flash questions

    I am new to photography but would like to do some indoor flash shots, specifically water drops and expand form there. I have 3 older flashes that I cannot mount to my camera because of voltage issues, and I want to use them for my slave flashes.

    Equipment wise I have a canon T2i, and 3 Vivitar flashes, an auto 201, an auto 252, and a 283, all working.

    I know there are different types of systems for triggering the slaves. I am not looking for a pocketwizard option, I am looking for more budget approach. The wife is already unhappy about some of my recent purchases lol.

    What would be the bottom to mid grade options available here? Thanks in advance for any help you can give a budding photographer.

  2. #2

    Join Date
    Oct 2010
    Location
    Cumbria
    Posts
    776
    Real Name
    Russell

    Re: Slave flash questions

    Hi, This may work but I say MAY!!
    Item number: 300706084194 on Ebay
    Believe you can also find the receivers without the transmitter
    Russ

  3. #3

    Join Date
    Aug 2010
    Location
    Stockholm, Sweden (and sometimes Santiago de Cuba)
    Posts
    1,088
    Real Name
    Urban Domeij

    Re: Slave flash questions

    You could use any slave trigger with your old flashes, but there are two caveats.

    One: You must not use TTL flash, but manual. TTL fires a "pre-flash" for measuring light through the lens. This small pre-flash will trigger your slaves before the camera takes the picture, and they will be empty when the shutter opens.

    Two: You should not expect the slaves to fire immediately as the built-in flash fires, but there is a short delay, which has two implications. One is that you might not get the whole image illuminated if you use the shortest sync time, so you might have to use a slightly longer shutter time. The other is that if your on-camera flash has a substantial influence over exposure, you may end up with the image double-exposed, as the slave flash triggers some nanoseconds later. Therefore, it is best if you use several slave flashes, that they are connected together with only one slave, and that you set minimum flash power on your on-camera flash, or bounce its light with a mirror, so it does not contribute greatly to the illumination of the scene if you want to stop movement.

    If you use radio remote, there is also a slight lapse between trigger pulse and flash firing, so in that case too, you might need a longer shutter time set than the minimum, i.e. if your camera has a shortest time of 1/200 for flash, you might need 1/160, or else you might get a black band in one edge of your image.

  4. #4

    Join Date
    Mar 2012
    Location
    United States
    Posts
    21
    Real Name
    William

    Re: Slave flash questions

    I checked out the link you gave Russ, but that setup specifically says no higher than 12V, the 201 pulls at least 19v according to my meter, the both the 252 and the 283 are a couple hundred I believe. I think my flashes would fry that setup.

    I would prefer to go wireless over optical I think. My camera does have the 1/200 sync speed like you say.

  5. #5
    benm's Avatar
    Join Date
    Feb 2010
    Location
    New Jersey, USA
    Posts
    316
    Real Name
    Ben

    Re: Slave flash questions

    I use one of these:

    Wein
    HS Hot Shoe Slave
    150' (45m) Maximum Range
    B&H # WEHS Mfr # 940-030 In Stock Price: $34.95

    The camera's pop-up flash signals the hot shoe slave to trigger the flash. The hot shoe slave attaches to the foot of your flash unit. You will need one for each flash unit. The unit also comes with a PC cord which you can use in case your flash unit is so old it does not have a hot shoe.

  6. #6
    inkista's Avatar
    Join Date
    Nov 2009
    Location
    California
    Posts
    1,502
    Real Name
    Kathy

    Re: Slave flash questions

    The problem here is that your Vivitars can send out exceedingly high sync voltages. As in some older 283s have been measured at 600V. So, the first thing is to measure the sync voltage of your flashes and see what neighborhood you're in. (Actually, though, the information on that page is old. The 6V limit on Canon hotshoes was for the first generation of Canon dSLRs. Anything newer than the original dRebel (300D) can withstand 250V on the hotshoe. Unfortunately, the older Vivitars can zap out 300V, so you can still fry your camera with 'em.) Chances are good that all the Yongnuo triggers are out of the running, since they're limited to 12 V. I'd actually point to the Cactus V5 triggers, as I think they can take up to 300V. But you may still need to be looking into a Wein Safesync to lower the sync voltage on the flash.

    The other possibility would be to grab something cheap like a Yongnuo YN-560 off of Amazon, and use its optical slave mode to trigger it from your pop-up flash. Problem is that the T2i's pop-up flash cannot be put into Manual mode, and always emits a pre-flash so you need an optical trigger that can ignore one, otherwise, I'd say get an optical slave to plug into a Vivitar. One more reason to go with a 600D instead of a 550D: you can put the pop-up into Manual.

  7. #7

    Join Date
    Dec 2008
    Location
    New Zealand
    Posts
    17,660
    Real Name
    Have a guess :)
    Another option might be to use a Hotshoe to PC adaptor, connecting into a distributor via a long cable, and some safe-sync adaptors.

    Quite a few parts, but they're all pretty cheap.

  8. #8

    Join Date
    Apr 2012
    Location
    Dunedin New Zealand
    Posts
    2,697
    Real Name
    J stands for John

    Re: Slave flash questions

    I organised some flash triggers quite awhile ago as something that 'might be useful'. later I wasn't sure if my camera emmited pre-flashes but I reasoned that if one partially masks the camera flash the pre-flash if I had it would be too weak to trigger the slave and only the main flash would ... it worked well for me.
    I bought mine from the UK but I have seen B&H advertising them for between US$18 and $37 each. They come with both 'hot shoes' to mount the flash on and with sockets for the flash's sync cord,[ also some have the standard quarter inch thread in the bottom for mounting] so if you take this option check what you are going to get.
    [These days there seem to be people importing and offering them on our local TM auction site here in NZ.]

    When you consider what flash triggers cost and what some American discounters ask for a YoungNuo flash complete with built in trigger you could perhaps dump your old stuff, as I virtually have :-) The YNs have an S2 mode which ignores pre-flash which is an added argument for this approach.

    I also have what looks like a Cowboy clone, four channel transmitter and two receivers for US$30 at Amazon. It works my YN560 AOK but my YN468 didn't fire ... yet to investigate why ... probably my setting up. I rarely use flash so no urgency :-)

Posting Permissions

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