Issue 2

In the last issue of Kelly’s Kamera Korner, I discussed different types of cameras, especially focusing on digital cameras.  If you are on a tight budget, I mentioned that you can get a good digital camera for under $200.  Anything with at least 3 megapixels can give you a quality image up to 8x10.  (The more megapixels the better.)  In this installment, I will explain megapixels and related terms in more detail.

The quality of a digital image is determined by its resolution.  Resolution is the number of pixels in a photograph.  A pixel is simply one of the many blocks of color which make up the image (think of a mosaic.)  The more pixels, the more detail the image has.  Resolution can be stated either by the dimensions of the image (1536 pixels x 2048 pixels) or by the total number of pixels (3,145,728, which is approximately 3.2 megapixels.)  A megapixel (MP) is one million pixels, and is a standard term in the features of digital cameras.

When trying to determine how many megapixels you need your camera to deliver, the main factor is how large you need to produce prints.  More megapixels will give you better quality at larger print sizes.  The standard for professional printing is 300 ppi.  PPI (pixels per inch) is the number of pixels per liner inch of printed photo.  For example, using our 3.2 MP camera above; 1536/300=5.1 and 2048/300=6.8; so we can print a professional quality photo at about 5x7 or smaller.  By experience, I have found 3.2 MP gives a good print at 8x10.  Doing the math, 1536/8=192 ppi, so approximately 200 ppi will also give you a good print.  So use 200-300 ppi as a general rule.  This chart should help:

Another thing to keep in mind, is that you need fewer pixels to display the image on a computer monitor than to print it.  Monitors only display at 72-96 ppi, so to completely fill up the screen, you only need 2 MP or less.  If you have a larger MP photo and plan to put it on a website or e-mail it to family, you should reduce the image size (and therefore the file size) so that it opens much faster across the internet.  If you aren’t sure when you take a photo if you will want to print it later, you should always shoot at the highest resolution (most cameras give you options).  When choosing to print later, you cannot make your photo larger, but you can always make it smaller.

Another factor related to resolution is file size.  Typically, the larger the resolution, the larger the file size.  Some cameras offer different quality settings with the same resolution.  For example, an 8 MP photo taken at the best quality could have a file size of 3-4 MB (megabytes).  Using a lower quality setting could keep the resolution (same pixel dimensions), but reduce the file size to 1-2 MB or less.  Again, you need to determine whether you want to fit more photos on your media card, or have the best quality for larger print sizes.  If you have a high MP camera, you will also need a large capacity media card and computer storage.

The bottom line when choosing a digital camera is to ask yourself how large you will need print your photos (are you really going to need anything bigger than an 8x10?) and balance the number of megapixels with other factors such as price and file storage.  The good news is, better technology is getting cheaper every day, so you can spring for the best, or take advantage of a low price while still getting necessary quality.

Stay tuned next time when we get more into the details of turning your photos into prints.  (If you have a question or topic you would like to see discussed, please e-mail ka_photos@comcast.net.)