A very good friend of the family asked if I could take pictures at his Mothers B-Day. I told him yes. The only problem is I'm new to shooting a 1D and I just got my 580EX Flash today. Now I know how to set everything Manually and use the flash more or less. I'm not that N00b. But since this is a party he wants me to just shoot candid moments here and there so my DISTANCE between subjects will be changing. I'm used to posed shots where I can set everything manually. Since this will be indoors should I just set my Camera to M and a high ISO for ambient lighting. Should I set the camerea to something like F2.8 and 1/60 and ISO 800? and let the flash do the rest? Or should I just Set cam to P and bounce off ceilings since it will be indoors in a house with a ceiling around 10-12 ft.