Megapixels: Should You Care?

If you're in close enough proximity to photography enthusiasts you're bound to hear something about megapixels. The rhetoric has dimmed some in the past few years as consumers are recognizing "megapixels" as less of a measurement of a camera's quality, and more for what it is, marketing voodoo. But is there anything behind the myth that megapixels equate to mega-quality?

Its true that as the era of digital photography has progressed, digital cameras have consistently gotten better and better at capturing stunning images. Todays high end cell phones with their tiny image sensors capture better images than my first digital camera back in the 90s. But in the early days of the Hubble Space Telescope it had only a 640k pixel sensor (that's HALF of 1 megapixel) and captured incredible images.

Pixels record image data. The more of them there are, the more image data you can potentially capture. But the more of them there are, the less "elbow room" they have on the image sensor, and so they need to be smaller. And when pixels are really small they don't record image data as well. That's why the Hubble took such fantastic images. While it only had 640,000 pixels, the pixels were huge, because they were rooted into a huge image sensor.

More pixels sometimes results in nicer images, provided those pixels aren't cramped onto a tiny sensor. Those extra pixels can also come in handy for a purpose that's often overlooked; cropping images. A high megapixel count can allow you to crop out unwanted outer portions of your image, isolating your subject better, while still providing enough pixels to generate a large print. So while more megapixels may not be important to you in terms of quality, keep in mind that all those megapixels give you a lot of compositional freedom when you post process your work.



At a point though be careful about excessive pixel counts. Again, cram too many pixels onto a small image sensor, and you have a recipe for trouble. Especially with regard to dynamic range. Dynamic Range is a term that refers to a camera's ability to record detail in very bright or very dark areas. And because tiny pixels don't capture light as well as larger pixels, detail in shadow or highlight areas tend to get lost in the shuffle. Ever look at a picture and notice the sky looked white, rather than a shade of gray? Or notice that the puffy clouds in your picture look more like melted marshmallows than cotton balls? Then you have experienced the problem of diminished dynamic range capture and it can be very frustrating for shooters who want to capture an image the same way they saw it with their eyes.

Pixels are important. Lots of pixels can be good for quality to a point but they can also be bad for tonal detail. Megapixel count shouldn't be the determining factor when shopping for a camera, but you should definitely take it into account when making your decision. Lots of pixels don't necessarily make for a great camera. And "not enough megapixels" doesn't mean a camera is sub par.