i have a client who wants me to do a poster 24" by 36" (Inches). And I have to include a big photo of him in it. If he gives me a photo file, how big will the file have to be in order to print at 300 dpi? I need the photo to fill up the space of the poster. It doesn't have to be a 24" by 36" inch photo, of course, but it has to be big enough to stand out because it's the only image in the poster. I tried to calculate the Megapixels and I got this rediculous answer: I need a 78 Megapixel image!!! This is how I calculated it: 300 dpi X 24 inches=7,200 pixels 300 dpi X 36 inches=10,800 pixels 7,200 x 10,800 pixels is approx. 77.8 Megapixels Ummm, I don't think my 6-megapixel camera can handle that!!! Am I missing something here???? Should I just take the pic with an analog camera instead?? How big can 35mm film be blown up to and still look okay? I bet this is a dumb question...oh, well, i need to know this!!