On Feb 5, 2006, at 8:25 PM, Brian Walters wrote:
If I wanted to do fill flash with either of the external units, I could do that by dialing in a negative amount of flash compensation? Or have I got that screwed up?
Yes. I normally set FEC some value between -.5 and -1.5EV to be more of a "fill" effect than the main light source with the built in flash. What you're doing is adjusting the total flash output power using a metering sensor. However, the adjustability is a bit coarse so I usually fall back on traditional manual controls to manage fill ... and since I don't own a dedicated external flash yet, I have to. ;-)
The basic rule is that, given a flash power setting, shutter speed controls ambient light exposure while aperture/distance controls the flash exposure. Balancing the two is a little tricky to conceptualize but once you "get it", it becomes easy. For a baseline to figure the proper settings, I use a hand-held flash and ambient incident meter.
The Kodak Professional and Pocket Photo Guides (do they still publish these?) provide very useful and easy to use flash fill calculation tools.
Godfrey
