Analog TTL because of the way it works. Now I'm writing from memory so please be cool with me ;)
Analog TTL: One of the contact from the hotshoe (yeah the second contact introduced with TTL system) basicaly has two state: closed or open. It remains closed all the time, bcomes open when flash must fire and goes bacl top closed when flash must stop (or the other way around BTW, not sure anymore). As simple as that. Digital TTL (SF-serie,Z-serie,MZ-serie except MZ-M): a lot of information or exchanged with the camera (not only start/stop for the flash) but flash zoom, Iso, aperture blablabla... Good luck to transmit that i you need a contact for each information, obviously there's a digital protocol at work here. PTTL ( = Digital TTL v2 ?) The one you know, loves or ... hate ;) There's a little bit more information passed with Analog TTL but not directly linked to TTL: in programmed mode, you need aperture etc... otherwise TTL doesn't work in P mode (see Metz flash limited compatibility in Analog TTL and P mode). -- Thibault Massart aka Thibouille ---------------------- K10D,Z1,SuperA,KX,MX, P30t and KR-10x ;) ... -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net
