AmbergrisCaye.com Home Forums Talk Belize Photographs Chat Picture IQ, Mega Pixels and Noise

Can anyone explain to me how the size and number of pixels on a given sensor size affects picture quality and in particular digital noise?

It seems to be received wisdom now that having fewer pixels on the same area of sensor can generate less noise, and I've seen people bandy around references to the size of each pixel and to the areas between the pixels as being significant. I'm not completely stupid and I do understand a bit about photography (coming from astronomy), but I don't follow these arguments at all.

Earlier this year I bought Canon's then top compact, the G10, which has 15mp on the sensor. That has now been superceded by the G11 which has 10mp on the same size sensor, albeit to a different design. The reason Canon gives is that this necessarily reduces digital noise and makes for better pictures. That view is being reiterated by photographers who've gone out and bought the new camera, including some who "upgraded" from the G10 to the G11. But looking at the photos posted by these people on various photo websites I'm far from convinced of the fact, and still not persuaded of the logic.

So, anyone understand and agree with the new thinking and able to explain it?

Peter
This is way over my head but I found this. About half way down the article it adddresses your questions
http://www.cambridgeincolour.com/tutorials/digital-camera-sensor-size.htm

Colin

Yet again my post was lost after I hit [enter]! I'm not going to re-type it all, just to say that that article doesn't talk much about pixels, and what it does say suggests that pixels are themselves sub-divided into "spots" which receive various colours. That isn't my understanding, as I always thought that the pixel was the smallest unit of light-gathering hardware. Maybe I'm wrong and that's at the root of my confusion.

I also said that the low-light pictures on that website are simply superb, and largely persuaded me to get my own 5D. Time has moved on since that article (it's about four years old) and two of the class-leading full-frame cameras are now from Nikon, the D3 and D700. If I were starting now I'd probably get one of those. But when I bought my 5D Nikon didn't make any full-frame-sensor cameras.