dotPhoto has just increased the single image upload from 12 MB to 16 MB for Club Members.
How big is that? The highest resolution for most printers is 300 dots per inch, so, if every single pixel were different, you could print a perfect 300 by 300 pixel-per-inch photo at 11 inches by 16 inches. This would be about 15.8 million pixels.
However, all pixels are NOT different: there are whole regions of sky and skin that have the same attributes, so most JPG files shrink significantly. In addition, large format printing devices (24″ to 60″) usually print at 72 to 100 dpi, so your 16MB upload can print the largest posters offered by dotPhoto.
One rule of thumb is that a each MegaPixel (MP) translates into roughly a half a MegaByte (MB), so a 32 megapixel camera will create roughly a 16 MB JPG file.
The Time to Upload Problem
Of course, very large images take longer to upload, so you might want to consider if you’re ever going to print more than a 4″ x 6″ print. Here are optimal image sizes in pixels for guidance in choosing image or print sizes:
Print in Inches | Pixels |
Wallet | Less than 480 x 640 |
4 x 6 (Minimum) | 480 x 640 |
4 x 6 (Best) | 768 x 1024 |
5 x 7 | 864 x 1152 |
8 x 10 | 1200 x 1600 |
11 x 14 | 1600 x 2000 |
16 x 20 | 1600 x 2000 |
20 x 30 | 1600 x 2000 |
24 x 36 | 1600 x 2400 |
30 x 40 | 2000 x 3000 |