• Digital photography has made printing photos an easy home project.photography image by peejay from Fotolia.com
  
  Printing digital photos at home makes it easy to scale a picture to be almost any size you want. But understanding the sizes of a planned photograph is vital when composing a shot. Different sizes have different width-to-height ratios. To figure out the ratio, simply reduce the measurements to their lowest common denominators. This means that a 3 by 5 picture would have a 3:5 ratio, while an 8 by 10 would have a 4:5 ratio. The 3 by 5 won't look exactly the same if it's blown up to an 8 by 10. The 3 by 5 is almost twice as wide as it is tall, while the 8 by 10 is much closer to being a square.
  
  

3 by 5

• The smallest standard photo size, 3 by 5 was once the most common size commercial print. This was the size of snapshots before 1980. The height/width ratio worked well with Instamatic and 110 film. You can still choose to print 3 by 5 photos, but you'll lose a portion of your picture when you print a digital photo as a 3 by 5 print. Four 3 by 5 pictures can be printed on an 8.5 by 11 sheet of photo paper.
  
  

4 by 6

• A 4 by 6 print is one of the most common sizes available today. It has a 2:3 ratio, and many digital cameras have a view screen at the same ratio to make picture-taking easier. Two 4 by 6 pictures can be printed on a single 8.5 by 11 sheet of photo paper, but there will be white space.
  
  

5 by 7

• This size is becoming more popular as digital photography grows. Because both measurements are prime numerals, the ratio is 5:7. This ratio is very close to that of the 4 by 6 print, so very little of a 4 by 6 print would be lost if it was blown up to a 5 by 7. This is the largest size that can be printed to fit two on an 8.5 by 11 sheet.
  
  

8 by 10

• This is the traditional portrait-size print. Its ratio of 4:5 makes it ideal to center a figure when the picture is printed lengthwise. When formatted on its other axis, a 10 by 8 print works well for groups. It is large enough to see details of individuals. An 8 by 10 picture can be centered on an 8.5 by 11 sheet of photo paper and still have a white border.