I love Thursday because it’s Guardian Technology day. Today, regular writer, Jack Schofield, tries to dispel the myth of mega pixels and cameras.

Jack Schofield: It pays to think big with digital camera sensors | Technology | The Guardian
In the days of film cameras, many or most people knew that a bigger negative generally produced a better quality image. The sensor in a digital camera is the equivalent of the film, and having a bigger sensor also makes a difference.

Nikons “prosumer” models such as the D40/50/60 have sensors that are roughly half the size of a 35mm negative, whereas the 12MP professional D3 has a full-frame 36mm x 24mm sensor, albeit for £3,300. If you want more, you can get a 39MP Hasselblad H3D-II with a sensor twice the size 48mm x 36mm, for something over £20,000, and thats without the lens.

Buy a compact camera, however, and the sensor could be anything from 2/3 8.8mm x 6.6mm to 1/2.5 5.8mm x 4.3mm. Im sure somebody can get 6MP out of a 25 sq mm sensor, but can it match 6MP from a Nikon D40s 370 sq mm sensor? No way.

So the question is “sq mm” not “Mega Px”.