Hi Gang................ Here's an interesting one............ I am shooting a wedding on Saturday. (that's fairly rare in itself) I am using my Canon 10d. Just for fun I figured to pack one of my Vivitar 283's as a back up to my dedicated Canon flash. I am NOT mounting the 283 on the hot shoe. When ever I take a shot with the 10d/283 combo I get the shot and then I get the dreaded Error 99 code in the display and I have to take the battery out to reset the camera. Sure makes me wonder whats up? Russ R.E. Baker Photography rebphoto@xxxxxxxxxxx Feed a Cat... Starve a Fever........