And to answer the question about DPI, no it doesn't matter. It's something that I don't even understand why it's there! If you are specifying in resolution, then you are specifying all of your dots. DPI doesn't relate to specified resolution, only to inches/centimeters/picas. I know your asking about 35mm film, so it would seem to make a difference, but since you can't specify size in Carrara (i.e. 35mm,) then dpi doesn't matter. Follow Dex's advice, and contact your film transfer house for what they want to receive. (I would guess sequential TIFs, without compression, @ 4K pixels wide minimum!) Good luck, and let us know what they tell you. :>