What Are Megapixels & How Many Do You Need

dslr-megapixels-how-many

Ask anyone what the most important feature of a camera is, and they’ll probably tell you it’s the amount of megapixels it has. Everyone wants more, because that results in super sharp photos and professional quality, right? False, megapixels and image quality are of course connected, but continue reading to see what truly matters.

What Is A Pixel?

A pixel is a simple dot, and when you have a million of them, they’re called a megapixel. A camera with 8 megapixels has 8 million little dots on its sensor, and together they create the image that you see on your LCD screen. It’s easy to assume that the more you have, the more details can be seen on your pictures, but there’s a limit with everything.

Let’s say you’re trying to draw a dog on a simple piece of paper, but instead of drawing lines, you’re placing a dot after dot. The more dots there are, the better it looks, but at a certain point you won’t really see any much difference unless you would look really close. It’s exactly the same with photography!

Every photograph you take is made of millions of little pixels, but just like with the example above, once you cross a certain limit you will hardly see any difference.

How Many Do You Need For High Quality?

Here are a couple of things that actually play an important role at getting high quality photographs:

  • Lens quality
  • Sensor and pixel size
  • Pixel technology
  • Good lighting conditions
  • Proper settings (shutter speed, aperture and so on)
  • Color & other algorithms

A good sensor with 2 megapixels will always win over a bad sensor with 20MP. Don’t get me wrong though, megapixels are important, but mostly when it comes to 1) cropping and 2) large printing. Sometimes your lens is just too short and you have to crop a bit to get closer to your subject, and in this case megapixels are your best friend!

The quality and size of pixels, as well as sensor, also matter a lot! A phone has a tiny sensor, and therefore tiny pixels (especially if there are many crammed in). An APS-C sensor for a DSLR is much bigger, and can therefore have bigger and “smarter” pixels that collect more light and information. As technology progresses smaller sensors obviously catch up, a lot of phones today beat cameras from just a couple of years ago, but when you take everything into account (low light performance, depth of field, sharpness etc.), bigger is almost always better here.

bird

I took this image with my Canon EOS 7D, an 18 megapixel camera.

bird-crop

And just for fun, here’s an even tighter crop! The image still looks sharp and acceptable, thanks to the amount of pixels of my camera.

bird-crop-3

I rarely crop my images though, but it definitely helps to know that I can rely on it in extreme cases!

Also, the majority of people share their photographs exclusively online, where they’re seen by other on monitors/phone screens. Let’s assume most use a Full HD monitor, which has a resolution of 1920×1080. If you multiply the numbers, you get 2.073,600, which is 2 million pixels, or in “photography terms”, 2 megapixels. The monitor can’t show any more details unless you zoom in, so hopefully you see now that just having a camera with more megapixels won’t automatically make your images look better.

Since plenty of cameras today come with 12MP and higher, you should focus on other things as well before buying one. In short, megapixels are good for the following:

  • Large printing
  • Cropping images
  • Selling your images (stock photography etc.)