I just shot an engagement party on a last minute request, as the couple's photographer could not make it. I got the call at 10am, and the event started at 2pm! Anyways, I brought my 5dMKII, 25-105 f4L, 70-200 2.8IS, and a few speedlight 430exII's. The party, which was mainly in the main dining room of a local golf country-club, had about 10 tables, the bride/groom table and a bar in the back. I seemed to have a problem with opening up to F4 and couldn't use a fast enough shutter speed most of the time, but I was afraid to bump up the ISO too much. Can someone tell me how successful they've been using the 5dMkII and how high they can bump ISO during indoor reception/party type shots and still have very sharp images? When I used the speedlight, of course, I was fine, but when I wanted natural light (one side of room was large window), it wasn't always working out for me. THis was my first "event" as I mainly specialize in studio work, and outdoor natural light. Any advice or comments would be appreciated. I know many people advocate using faster glass, (2.8, 1.8, etc) but when you are opening up to 2.8, or lower, how do you keep multiple people in focus when your distance to subject is only about 8 feet?