> Date: Thu, 18 Mar 1999 08:13:07 -0500 > From: Thierry PERTUY <[EMAIL PROTECTED]> > Subject: RE: F100 and flash questions [v04.n310/21] > Message: 21 > > > The pre-flashes are used to detect highly reflective surfaces in the > > image (like mirrors or white walls) that aren't lit by the ambient > > light. If you bounce the flash, you'll have to compensate for those > > yourself. > > Ok. Will do but I don't understand why the pre-flashes couldn't work with > indirect flashing. > Because the preflashes also work in conjunction with the "D" lenses -- the distance information from the lens, plus the known power of the pre-flashes provides a way to gauge the lightness/darkness/reflectivity of the subject. Once you tilt/swivel the head, the preflashes are turned off; they couldn't possibly be useful because now the distance they travel is unknown -- let alone what type of surface they're bouncing off to hit your subject and bounce back into the lens! Chris -- Wilderness, wilderness... we scarely know what we mean _/ Christopher Somers by the term, though the sound of it draws all whose _/ Rise Technology nerves and emotions have not yet been irreparably _/ www.rise.com stunned, deadened, numbed by the caterwauling of _/--------------------------- commerce, the sweating scramble for profit and / Gallery: www.flash.net/~jboy domination. (Edward Abbey)