10D & flash on Xmas Day

DATE: Christmas Day LOCATION: My 10x10 living room without possibility of bounce flash CAST: 25 family members SUBJECT: Group shot GEAR: 10D, 17-40 L lens and 550 EX flash mounted above camera on a Stroboframe bracket

QUESTION(S) Can someone pass on to me some recommendations re shooting mode, f-stop, depth of field, exposure comp, stofen diffuser (which I have), white balance (the room will have both daylight and tungsten lights). I'm also forced into shooting at a slight angle into a window that can't be blocked out--no shades and no drapes. Should I exp comp for that with a + something or other, depending upon what the first shots look like in the LCD?

The depth of the 25-person group will probably extend from 6 feet in front of the camera back another 8 feet. I took a similar shot two years ago with a G1 and no special settings. Came out OK, but with my current gear I'd like to improve upon it.

Just when I thought I was having a stress-free holiday break....

Floyd

I just went through the same craziness preparing for my family Christmas party this past Saturday. I used a Quantum Q Flash T2D instead of the 550 EX. The week before I experimented at home with the lens 16-35 f/2.8, bracket, and flash. I found myself using ETTL with a +1 FEC with the flash tilted at a 45-60 degree angle with no diffuser (reflector and bulb only). I'm not suggesting you use my settings, only that since it's your living room, take a bunch of test shots before the party till you find settings you like. I found the histogram to be very helpful. Don't judge by the LCD as it's deceptively bright. You might also want to use white 3x5 inch index cards with the setup for each picture written on the card and the card placed in the photo where you will be able to read it. If you really want to feel professional, you can also stick an 18% Kodak grey card in there to add a reference for exposure. Later, you can put all the photos on proof sheets and decide which settings worked the best.
Happy Holidays,
Scott