What does the term ‘pixel density’ mean? Does this parameter affect image quality in any way?
Sameer Mirchandani, via email
Pixel density refers to the total number of pixels on an imaging sensor, divided by the area of that sensor. It is basically used to indicate the distance between each photo pixel, that is, how closely packed the sensor is with pixels. Thus, if the sensor size is greater, the pixel density of the camera is lesser. Pixel density does influence image quality to a certain degree.
A lower pixel density often leads to improved dynamic range and better control over noise. This is so, because when the distance between each imaging pixel is more, the pixels literally have more breathing space, and their light-gathering ability improves. This is also the reason why the image quality delivered by a cell phone camera, compact camera and a DSLR is different, even if all three have the same resolution. However, while comparing image quality, pixel density is not the only criterion one must take into account. Technology is constantly developing, and different manufacturers’ sensors work in different ways. So one must understand that, pixel density is one of the many factors that eventually determine image quality.