Which is more important? sensor size or number of megapixels? explain both.?

Question

Which is more important? sensor size or number of megapixels? explain both.?

Answer 1

Sensor size !

There are any number of 10MP cameras with small sensors. I have cameras in both this category and DSLR with a bigger sensor with the same 10MP's and there is a huge difference in the quality of the images.

Not all pixels are equal. The link below explains sensors in great detail.

Link :  http://www.cambridgeincolour.com/tutoria...

Link :  http://www.dpreview.com/news/0210/021004...

Link :  http://www.bobatkins.com/photography/dig...

Answer 2

Sensor size. That's why Canon and Nikon (and soon, Sony) offer full-frame (24mm x36mm) DSLR cameras.

The power of marketing (aka hype) has convinced many people that the more pixels the better. So we now see point & shoot cameras boasting 10 or 12 megapixels. Unfortunately, the sensor in the typical digicam is approximately 15 times smaller than the sensor in a typical DSLR like the Sony A300 or Nikon D40x or Canon XSi.

Since the sensor size remains the same the only way to stuff more pixels into it is to make the pixels smaller. Smaller pixels are less sensitive to light (and this has NOTHING to do with ISO) and need a "boost". This results in excessive digital noise beginning at ISO 400. In some digicams digital noise becomes noticeable at ISO 200.

So a DSLR with as few as 6 megapixels will totally blow away a 10 megapixel digicam when it comes to image quality.