Have you ever taken a great photo with your digital camera, it looks great on your computer screen but when your print it, it looks like a bad mosaic? This is most commonly due to a low resolution setting on your camera.
Most professional photo printers print between 150 and 300 pixels per inch or "ppi" to achieve photographic quality. If you wanted to enlarge a photo from your digital camera to an 8x10 print, that means you would have to take the photo at a minimum resolution of 150ppi or 1200 x 1500 pixels (8x150 + 10x150).
Therefore, it is advisable to have your camera always set to the highest jpeg resolution for the most flexibility when it comes to printing your photos. One drawback to this is that the larger resolution means larger file sizes for your photos, decreasing the amount of photos you can keep on your camera at any one time.
My photos look fine on my computer screen why don't that print well!
Don't be deceived by how your photos appear on your computer monitor, your monitor displays photos at 72 ppi, whereas photos are printed at more than twice that resolution.
When you zoom in on a photo why does your print quality suffer
Alright, so you've taken a great photo of the family, but it looks like you've taken it from a mile away! So you zoom in and crop it on your photo editor and want to print it. However, your online photofinishing service alerts you that the image quality is poor and won't print well.
Think of your digital photo as an oil painting made up of thousands of brushstrokes. Your photo is made up of a limited number of strokes or "pixels" determined by the resolution setting you used on your camera when you originally took the photo.
When you zoom in on the photo, the number of brushstrokes or "pixels" you are looking at is reduced, depending on how much you zoom in. Up close you can see the brushstrokes (or pixels) and the picture doesn't make much sense (i.e., the resolution is poor), whereas from afar it looks like a complete, smooth image.
Your built-in digital zoom on your camera works in the same way. That is why it is advisable to avoid using your digital zoom where possible. You can always zoom in using your photo editing software later, but you can never zoom out from a photo already taken.
Hope this helps....
Keep taking pictures!