| Author | Thread |
|
|
10/06/2005 10:27:26 PM · #1 |
I just bought some fairly decent strobe lights which work fine using the PC sync cord with my 20D. When using the built-in flash to set off the strobes, the picture comes out dark as if the strobes don't work even though they go off (of course covering the built in flash not to interfere with the test so it only goes off to trigger the strobes).
The strobes flash last about 1/1000 of a second, so I assume they are done flashing before the camera has even opened the shutter and therefore don't affect the picture anymore. Has anyone had a similar problem? Or has anyone tweaked a camera to make it work? Thanks. |
|
|
|
10/06/2005 11:58:51 PM · #2 |
Originally posted by kayla:
I just bought some fairly decent strobe lights which work fine using the PC sync cord with my 20D. When using the built-in flash to set off the strobes, the picture comes out dark as if the strobes don't work even though they go off (of course covering the built in flash not to interfere with the test so it only goes off to trigger the strobes).
The strobes flash last about 1/1000 of a second, so I assume they are done flashing before the camera has even opened the shutter and therefore don't affect the picture anymore. Has anyone had a similar problem? Or has anyone tweaked a camera to make it work? Thanks. |
The on-camera flash uses a pre-flash for E-TTL so you need a "digital" sync that will ignore that first pulse and only trigger on the main burst.
Message edited by author 2005-10-07 04:00:29.
|
|
|
|
10/07/2005 12:11:40 AM · #3 |
Or turn the ETTL-II off and do everything manually. Though I'm not sure if you can do this.
I think I read somewhere about some intelligent optical triggers that can be set to fire on the 2nd flash, however I think this would mess up the E-TTL light meterning. |
|
|
|
10/07/2005 04:28:26 AM · #4 |
Originally posted by aKiwi:
Or turn the ETTL-II off and do everything manually. Though I'm not sure if you can do this.
I think I read somewhere about some intelligent optical triggers that can be set to fire on the 2nd flash, however I think this would mess up the E-TTL light meterning. |
E-TTL won't work with studio strobes anyway..
|
|
|
|
10/07/2005 04:43:18 AM · #5 |
| I had the same problem with my Alein Bees... I just gave up and used the synch cords, so I am interested in hearing how to resolve this. |
|
|
|
10/07/2005 04:46:59 AM · #6 |
Originally posted by toddhead:
I had the same problem with my Alein Bees... I just gave up and used the synch cords, so I am interested in hearing how to resolve this. |
ditto:
I found if you set a hot shoe mounted flash on manual, and set it to a very low power setting, I can get it to trigger, but not in every situation. even when setting a 580ex on master, it still doesn't stop the pre-flashes.
|
|
|
|
10/07/2005 04:55:17 AM · #7 |
Originally posted by ericlimon:
even when setting a 580ex on master, it still doesn't stop the pre-flashes. |
Setting the flash to full-manual is the only way to disable the metering pre-flashes. When using multiple Canon Speedlights in a master/slave configuration, the flash power calculations are "sent" to the slave units by encoded pulses of light just before the shutter opens, so putting it in "Master" mode will actually increase (although maybe not perceptibly) the number of flashes before the "real" flash. (For more information on this, you should check out Canon's "FlashWork" brochure.)
If you don't like being "tethered" to a sync cord, your best bet (especially in terms of reliability) is to use something like a PocketWizard or MicroSync (if you don't need the range/features/compatability of the PocketWizards) to trigger your strobes. You can find other cheap RF-based (radio, instead of light) slaves on eBay... but remember... you get what you pay for...
Message edited by author 2005-10-07 09:03:45. |
|
|
|
10/07/2005 08:16:16 AM · #8 |
| Thank you so much for the excellent info. That MicroSync looks really interesting. It can serve as a wireless strobe trigger as well as a wireless remote control for the camera. Awesome. |
|
