Originally posted by stepmac
Does the megapixel sensor rating make that much diff to a guy who takes pics for his own pleasure and occasionally blows one up to 8x10...or a bit larger?
Are the camera manufacturers just pulling our chains?
IMO,
No and yes! But be sure to read the last paragraph.
The average non-pro user is probably printing though Snapfish or the like. They just aren't very many custom labs in most towns. They let you upload any size file you want and then they compress it before it even goes to the automated printing process. While they won't give you any definite information so that you can make an educated choice, I can tell you that if you are uploading more than 300 DPI print size you are just wasting your bandwidth.
I testing this by scanning the same 4 x 6 print at 75dpi, 150dpi and 300dpi and then paying to have them printed. I was warned at upload that the 75dpi file would not result in an acceptable picture and it did not. When I place the 150dpi and the 300dpi side by side I can see no appreciable difference.
This new Epson scanner I purchased says high quality for a reflective scans (photos) is 225dpi. Lets just stay with 300dpi for now.
300 dpi @ 8x10 = 2400 x 3000
300 dpi @ 10 x 12 = 3000 x 3600
300 dpi @ 12 x 14 = 3600 x 4200
My wife just printed a 5x7 crop that was 2592 x 1456 taken with a 5 mp Canon (2592 x 1944) that is entirely acceptable.
One thing more pixels will let you do is crop more more and still have an image you are pleased to print. You might only want the pixels displayed in 1/3 of the initial image for you print and if you have the file size to start with you can crop and still be very pleased with the results. A camera with at least 10mp will allow you to do something approaching a 100% crop with a sharp image and still be pleased with the results when printed.