September 6, 2009

Choosing How Many Megapixels

Nine Pipes Wildlife Refuge, Montana
Made with a 1.9 megapixel camera
In an earlier post I described what a megapixel is and how to find out how many megapixels your digital camera can produce. The next step is setting the camera to record the number of megapixels you need for your images.

Check your camera manual index or table of contents for "Picture Size" or "Resolution" or even "Quality". These are all names for the same thing: how big is the photo your camera is going to record.

Depending on your camera, the sizes are given in different formats. Some simple cameras use stars; three stars is a larger picture than two stars. Other cameras use letters---L, M and S for Large, Medium and Small photos. Still other models give the dimensions of the picture in pixels, for example, 3072 x 2304. Others display only the largest number of pixels on the longest side of the photo, 3072 in the previous example. Finally, some cameras show the picture size in megapixels (abbreviated "MP"), such as 3mp or 6mp.

Changing the number of megapixels your camera records is, literally, changing how big your digital picture is. A photo that is 1500 pixels x 1000 pixels is half the size of an image that is 3000 pixels x 2000 pixels. The more pixels you have in your photo, the more space it takes to store on your memory card. But memory cards with lots of storage capacity are inexpensive these days. So if you can't save enough photos on your current memory card, buy another one. (It's always good to have a spare card anyway.)

Given all these options, how do you know what size of picture to choose? It's actually really simple. Use the largest size, the maximum amount of pixels, that your camera can produce. If you are using all the pixels that the camera makes, you are taking full advantage of its maximum quality. And, since you probably paid more for a camera with more pixels, you are getting your money's worth!

Also, the more pixels in your digital photo, the larger you can print it and keep all the details sharp (provided they were recorded sharply when you took the photo). And you can crop the picture (delete pixels from the edges) to better emphasize your subject and still have enough pixels left over for a print. If you need the picture to be smaller, such as for email or web pages, you can change the number of pixels after you take the photo.

Nearly all digital cameras today have more than enough pixels for excellent small, medium and large prints. If your camera has at least 6 megapixels, it can produce photos that can be printed up to 15x10 inches (before cropping). A 12 megapixel camera can make prints up to 20x15 inches (before cropping).

So set your digital camera to use all its megapixels and start clicking the shutter button!