Megapixels

When you choose a camera you will need to decide what size the largest picture you will want to print will be. For the most part you can determine the size of a photo quality picture you can get from your camera by its megapixel. This is more true for point and shoot cameras then it will be for DLSR cameras.

Here is how to do the math. A megapixel is approximately 1 million pixels. A true photo quality print will be printed using 300 DPI (dots per inch).

What that means is that if you want an 8 x 10 print you first need to multiply:
8 x 300 = 2400 pixels
and
10 x 300 = 3000 pixels

This gives you the pixel length and width of your photo. Now you need to find the the number of pixels in the 8 x 10 rectangle. Calculate the "square feet" or in this case, "square pixels" by multiplying:

2400 x 3000 = 7,200,000 pixels

Remember - a megapixel is approximately 1 million pixels. Now, divide the "square pixels" by a million pixels to see how many megapixels your picture will be:

7,200,000/1,000,000 = 7.2 megapixel

This means that you will need a 7.2 megapixel camera to print an 8x10 photo and photo quality.

Please note: this is just a ballpark way of figuring it out. In actuality, you may be able to achieve an 8 x 10 photo quality print using a 4 or 5 megapixel camera if you have a good sensor or use good photo editing software afterwards. Also, shooting in RAW format instead of jpeg will give you better results especially if you have software on your computer that can render the raw image, edit, and or print it.

This website has a great resource for explaining further what megapixels are and how they affect images.

To find out how many megapixels your camera has, check your owners manual.

Last modified: Thursday, July 22, 2010, 11:55 AM