[sassan]

Hi Clive.

I hope I understand your question correctly and following can help.

Not familiar with your powerful studio flash but I can close my eyes and see that you don’t have the same number of contacts at your flash end when compare to base of your EX 580. In other words your studio flash is not dedicated for the camera so can’t read the rest.

You might be able to achieve what you like to do by setting Elinchrom stobes on slave trigger, attaching your EX 580 to 40D body, keeping menu of camera for 2nd curtain and shuttle etc as needed but EX 580’s out put at least 4 stop lower than needed light for actual image or a way to simply direct the EX flash toward the Slave trigger and not subject then go with rest of image taking that should give your right duration of ghost subject with a desired clear subject at the end of action, i.e. 2nd curtain effect.