It really frustrates me. All I want to do is master the technique of taking a simple outdoor portrait using fill flash, but I might as well be planning to take over the world. I've been practicing and practicing, but nothing seems to work. I have a Canon 10D, 28-135IS, and 420EX flash. I've shot in all modes (program, av, tv, and manual) and got disappointing results no matter what I do. Can someone help me put this to bed once and for all. I'm ready to give up.
I don't know what you are doing wrong, but I can tell you a couple mistakes I've been known to make:
1. I like to set the flash exp. comp. to 0 indoors, forget that I want -2/3 stop for fill and blow highlights with the flash outdoors. This is the old standby screwup for me. It's especially a good one because it's hard to see the histogram in bright light to notice the blown highlights.
2. Another favorite, shoot a few shots in Av and then decide to fill flash for some shadows. I then forget that while I was just shooting at perhaps 1/1000 shutter speed, the flash synch will cut that to 1/200. EV 16, f/5.6 and synch speed of 1/200 = about three stops overexposed. If you are in Av mode and shooting, make sure that the combination of aperture you select does not require a shutter speed over 1/200 when you turn the flash on. I also didn't chimp the histogram that time because the sun was so bright. At least I did manage to lighten up those shadows under hat bills! No shadows whatsoever!