Arvid, You have to set the 550ex to HSS (High Speed Sync) by pushing the (+) and (-) buttons at the back of the unit at the same time. This same combination also sets second curtain sync. I think the cycle is <normal mode> =(+)(-)=> <HSS> =(+)(-)=> <Second Curtain Sync> =(+)(-)=> <normal mode>. Please somebody correct it in case is mixed them up, but in any case, you'll see an icon on the LCD panel of the 550 with an "H" and a bolt symbol for HSS and "2nd" for second curtain sync.
With HSS you have flash synchronization with all speeds above 1/125, but be aware that the GN of the flash decreases dramatically when the shutter speed decreases (towards 1/4000, the max shutter speed for the EOS30) so be prepared to get as close as possible to your subject. Kind regards, Gerard. PS: Now I know where I'm going to borrow a second 550EX :-) PSS: Wij moeten nog een keer afspreken om dia's van mekaar te bekijken... laatste dagen zijn wat moeilijk geweest (kind ziek, ik ziek, vrouw zwanger, enz...) maar v.a. volgende week moet alles terug naar "normaal" staat komen (hoop ik). Wij spreken en en andere af... :-) * **** ******* *********************************************************** * For list instructions, including unsubscribe, see: * http://www.a1.nl/phomepag/markerink/eos_list.htm ***********************************************************
