It's that time of the year as a attendee I was asked to take some photo's. I usually do landscapes with a tripod so these things were never an issue for me. Edit - D600, SB800, 70-200 F4 VR. I was at ISO 2800, F4, 1/60. I set auto ISO a min of 1/60. With people gathering events, would you use fill light or key light? With key light one could maybe underexpose the scene maybe reaching 1/125, a lower ISO, and use the light to fully light up the person. This would slow down the flash right. The ambient background would be darker as well for an event place. If it was fill light then one would need a 2.8 lens which I don't have and or up the ISO and if one wanted 1/125 instead. On the occasion I used fill light and stuck with 1/60. I find 1/60 was ok and that is what some people have said they use in the situation, compromises right. Not saying I wouldn't mind 1/125. I was using my 70-200mm F4 VR with stabiliser on. I was able to use the ceiling and bounce it, but hey - if the ceiling was not white would you just used a on camera flash diffuser and live with that? Cheers.