Canon 550 EX as a slave for 20D

[Andrew Teakle]

Hi all,

I have been trying to use my 550 EX as a slave unit being activated by the on-camera flash of the Canon 20D. I can do this with my Sigma flash unit as a "dumb" slave ie: it just fires with the output set manually, not TTL. I can use the Sigma as a TTL slave using the 550 EX as a master, but when I want to save weight and bring just one flash, I haven't been able to work out how to set off the 550 EX (channel 1, 2, 3 or 4, or as a "dumb" slave on channel 0).

Is this possible, or should I just bring the Sigma?

Cheers,

Andrew

[francois]

Hi all,

I have been trying to use my 550 EX as a slave unit being activated by the on-camera flash of the Canon 20D. I can do this with my Sigma flash unit as a "dumb" slave ie: it just fires with the output set manually, not TTL. I can use the Sigma as a TTL slave using the 550 EX as a master, but when I want to save weight and bring just one flash, I haven't been able to work out how to set off the 550 EX (channel 1, 2, 3 or 4, or as a "dumb" slave on channel 0).

Is this possible, or should I just bring the Sigma?

Cheers,

Andrew
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I don't think that it is possible. You need either a Canon unit as master or the ST-E2 transmitter.

[Andrew Teakle]

I don't think that it is possible. You need either a Canon unit as master or the ST-E2 transmitter.
[a href=\"index.php?act=findpost&pid=57294\"][{POST_SNAPBACK}][/a]

Thanks Francois,

This must also go on my wishlist for the replacement of the 20D: a wireless flash controller for the current range of TTL II flash units. With a single on-camera flash and a wireless unit that can be positioned independantly and with complete control of its output, terrific lighting effects can be achieved (especially for small and close subjects). This is alongside a 10-12MP sensor, weathersealing, dedicated MLU, larger and brighter LCD screen, extended ISO (lower and higher), and auto sensor cleaning...Gee, what a camera!  

All the best,

Andrew

[francois]

Thanks Francois,

This must also go on my wishlist for the replacement of the 20D: a wireless flash controller for the current range of TTL II flash units. With a single on-camera flash and a wireless unit that can be positioned independantly and with complete control of its output, terrific lighting effects can be achieved (especially for small and close subjects). This is alongside a 10-12MP sensor, weathersealing, dedicated MLU, larger and brighter LCD screen, extended ISO (lower and higher), and auto sensor cleaning...Gee, what a camera!  

All the best,

Andrew
[a href=\"index.php?act=findpost&pid=57326\"][{POST_SNAPBACK}][/a]

There's a long way to the elusive "perfect" camera but I don't understand Canon on that feature, other brands allow triggering slave units from the built-in flash. Oh well, I guess it's just another trick to sell the ST-E2 transmitter...