PDA

View Full Version : Slave flashes and 300D!


ERamos
15th of November 2004 (Mon), 11:47
I would like to know if I can fire a cheap Slave Bulb or Slave Flash with my Digital Rebel, I won't be using it often, but sometimes I find my self in situations where I know an extra flash would be of a lot of help.

As you noticed I own a Speedlite 220EX and plan to get the off-shoe cord to fire it and use the slave as a bounce light.

Thanks in advance.

:?: :?: :?:

cmM
15th of November 2004 (Mon), 11:53
well you could get an AC strobe and use it as an optical slave. Other than that... another flash and pocket wizards to trigger both of them, but that won't be cheap. You can't use the 220EX in a wireless setup right ?

OviV
15th of November 2004 (Mon), 11:58
Your problem is going to be the pre-flash that is emitted by Cannon ETTL. This pre-flash will fire off your slaves too early. You can get around this by putting your camera on manual and your flash on manual (if it is capable). You will then have to manually set your apperture to control exposure. You can set your shutter speed at 1/60 for most every scenario. Again, you will need a flash capable of manual I don't know if the 220 can be set to manual.

Ovi

Jon
15th of November 2004 (Mon), 12:00
If you're expecting to use the 220EX or the built-in flash as the trigger for an optical slave, I'm afraid you're out of luck. You can't disable E-TTL and the pre-flash with either of those, so you'll be setting off the external flash with the preflash rather than the main flash. You might be able to tape over the E-TTL contacts on the flash/shoe to make the camera think it's a dumb flash, but then you'd be using the 220 at full power.

ERamos
15th of November 2004 (Mon), 12:49
Thanks to everyone for your help.
I was kind of concerned about the E-TTL (cannot disable), but never thougth of taping the E-TTL contacts, that's a good and cheap idea, I don't think I need a 420EX, much less a 550EX, because I can't afford neither one, and because I shoot landscape most of the time.

Thanks for clarifying my mind and for the answers, regards.

:) :) :)

Headcase650
15th of November 2004 (Mon), 14:23
If you look around there are some new optical slave shoes that are made for E-TTL type systems, they clame to not fire on the preflash put out by your camera. I do not have any experiance with them but I did notice they were more than twice the cost of a regular optical slave.