Pixeltje Blog

For years, camera manufacturers have been building cameras with more and more pixels. It seems/seemed as if there is no limit to the number of megapixels you can get in your camera.

In theory, this is true: the more pixels you have in your camera, the more details you can capture, and the larger the prints you can make. However, we also all want small, compact cameras. So the camera manufacturers do their best to fit this larger number of pixels into the same or an even smaller camera housing, with the same sensor and lens size. And that’s where it gets tricky, because if you increase the number of pixels and keep the sensor size the same, the size of each pixel has to decrease. And a smaller pixel can capture less light, which results in relatively more noise. So the resulting images are noisier. Also, it does not make much sense to have a sensor that can capture more details if your lens does not let those details pass through. The lens should therefore also be replaced by one with a higher quality, and better lenses are typically also bigger.

So, there is an optimum. And the people at Image Engineering have measured that the optimum for a compact camera is 6 megapixels. They have even devoted a website to it. Of course, this does not hold if you also increase the sensor size (for example in SLR cameras). It is therefore better to say that the optimal pixel size is 3 micrometer. Depending on the sensor size, one can then compute the optimal number of pixels.