i have a wedding to shoot next month and would like to know which is more widely used and why - positive or negative film? the 'why?' is the most valuable information for me. i'll be using medium format for some formal family shots and shoot the rest on 35mm, candid. i'm going to use all colour, (clients request) but some stuff that i think would work well in black and white, i'll scan and convert so i'd also like to hear from anyone with experience in this area.