What is a megapixel

By Charles Hopkins Published 07/6/2006 | Arts and Culture

What is a megapixel

One of the most common terms used in digital photography is megapixel. It comes from the word pixel which in computer lingo, means, 'a dot.' These little dots, or pixels, store color information and their number per square inch determines the quality of the picture. The picture that has more pixels per square inch is much better than pictures that have less number of pixels.

The same applies to digital cameras. A five megapixel camera is considered much superior to a one megapixel camera. This is because the pictures taken by a five megapixel camera will have much higher resolution than those taken by a one megapixel camera.

In simple metric terms, a megapixel is equivalent to one million pixels. When a camera seller shows a 1 megapixel camera it means that this camera can shoot a picture that can have one million pixels. Similarly, a ten megapixels camera can shoot an image that can have ten million pixels.

Professional photographers have now moved to 14 MP to 22 MP cameras. These cameras can shoot pictures whose megapixel count ranges from a mind boggling 14 million to 22 million pixels. The resolution of these pictures is very high, and so is their sharpness and clarity. They can easily be blown into posters without losing their sharp look.

In contrast, pictures taken by a 1 megapixel camera can only be suited for use on the web. They will lose sharpness if they are blow beyond a certain point. So, when selecting a camera you must decide the purpose. There is no point in going for a 14 MP camera if you want to use it for home photography. The picture quality will be good, but so will be the cost. It is much better to go for 3 or 4 MP cameras. These produce stunning images, if used with the right amount of creativity and are far more affordable. 

Another way to define megapixel is to take the example of a computer screen whose size is 1024 by 768 pixels. In other words, the computer screen is made of 786,432 pixels, the number arrived by multiplying 1024 pixels by 768 pixels. This is quite close to a million pixels. When you contrast this computer screen with the earlier computer screens -- which were 800 by 600 pixels -- you will realize why you like your present computer screens more. They have better clarity because they have more pixels.

The megapixel count is also used to decide the size of a print. You can print better pictures when you are using a camera with a high megapixel number. Thus, a 3MP camera can at best provide you 4x6 inch prints, while a 4 or 5MP digital camera can deliver excellent 8x10 inch prints.

But if you want to take a picture that needs to be printed as a banner then you need a10MP or 14 MP camera. Only these cameras can provide the resolution that can allow a picture to be blown to that size without losing clarity.