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mcolella
13th of October 2003 (Mon), 07:01
Does anybody know a way to make flash working in auto mode while using M mode?

I use G3 in macro shot (reversed 50 mm or closeup lens using an intarnal flash diffuser similar to one shown on http://www.iaw.com/~pturton/diffuser/index.htm) and when I shot macros outdoor in sunlight, often the standard synchro speed (1/60) is slow enuogth to get shot moved (even if camera shakes or subject moves). Of course using highest available synchro (1/250) fixes the problem, but the only way to set such speed still controlling aperture (I must use f8 to have max DOF), is to use M mode causing flash to be switched to manual mode loosing in this way the E-TLL automatic flash exposition.
According with 420EX external flash unit users's manual, it seems to be a G3 limitation since 420EX can work in automatic mode with M mode (on cameras other than G3).

Regards
M

mcolella
15th of October 2003 (Wed), 10:22
A solution to this problem is listed here: (http://photography-on-the.net/forum/showthread.php?t=18694)

alan-G3
20th of October 2003 (Mon), 04:18
Hi There

An interesting aspect of setting manual mode is that there is NO PRE flash and the internal flash is very low powered. I guess that this intended to trigger "normal" slaves but canon do no tell you.

There are also small external slave/flash guns "Sunpak Digi Flash" which can help with adding some modeling to Flash shots but it has a limited synch speed. The two combined flashes seem to take care of quenching in combination with each other. I guess that they each detect the extra light from the other flash.

Regards
Alan