Some friends invited me to a seat at their table for a local charity fundraising banquet. Since they had an inside connection to the host, and since I was the only person who showed up with any camera equipment better than point-and-shoot, I did an impromptu photo shoot of the event for the use of the organization's director. I had my Rebel XS body and used three fast primes -- EF 50mm f/1.4 USM, EF 85mm f/1.8 USM, and EF 28mm f/2.8. I seemed to get the best results with 800 ISO and f/2 (+/- a stop or two), so I shot most of my images at those settings an selected the exposure time as required to capture enough light -- usually between 1/40 and 1/125.
The lighting and the subjects were both very challenging. The ceiling was about 15' overhead, open-architecture, and painted black. Illumination was entirely from overhead incandescent floods and a smattering of decorative candles. The walls were a dull tan and the carpet was a grey-red color. Prior to dinner people were milling about, eating hors d'ourves, investigating the silent auction items, talking, etc. so there was always some movement.
I got a decent 35 or 40 images out of the 100-odd frames that I shot, but very few were especially sharp. The focus distance for the 50mm and the 85mm tended to be pretty narrow, even when shooting across the room, which produced a lot of bokeh, both foreground and background, that wasn't always intended. Many images were also very grainy and required heavy noise reduction with post-processing.
All things considered, I'm pretty happy with the results considering the lighting and my lack of experience, but what things should I do to improve my technique in a future setting of this sort?