??? megapixels

[nuts and bolts]

Greatings all you photojunkies

I am trying to understand the whole pixel good and bad scenario better.  I have read a fair amount on it now and am getting the overall impression that less pixels can give you superior pictures due to size of photosites (better processing of the absorbed light ) and hence (e.g) the Nikon D2H still running at 4 MP as a pro camera.  The limitation coming in when you enlarge it.

 I have read a lot to suggest that 4 MP could give better pictures, but surely when a manufacturer produces a 12 or 16 MP CCD or CMOS chip they do so with improved technology and thus a 12 MP chip on a camera you buy today will equal the quality of the 6 MP camera you bought 2 years ago in relation to noise etc.  Of course one assumes this new technology will also be used in the 4 MP camera to further improve it.

When you are looking at CCD's and CMOS (or other chips like JFET - what else is there) what are the things you consider when you want to rate them.  Is there a definitive on which technology is better (personally from what I have read FOVEAN technology makes the most sense) and short of hours of wasted internet searching (a liberty I do not have) where are the best places to get the information?

I know there is a lot to consider when it comes to buying a camera, I own a D70, its capabilities are superior to my current level of photography, but as I love photography I wish to learn as much about the equipment I use, or may choose to use in the future as possible.

Look forward to your input.

[BernardLanguillier]

A lot has been written on this already, you might want to spend a few days browsing forums...

Overall though:

- There is a fairly good correlation between pixel count and actual image detail when the sensors are used at their base ISO. At higher ISO, things become more complex, but the latest CMOS sensors appear to retain a better signal to noise ratio than CCDs,
- There are however some variations that mostly result from the use of more or less strong AA filters in front of the sensors. No AA filter means more detail, but also more moire,
- Image detail isn't the only important dimension of image quality. Dynamic range, shadow noise, highlight roll out,... are all critical as well,
- Selecting a camera based on the sensor technology it uses doesn't make a lot of sense IMHO. There are many varieties of CCDs, just like there are many varities of CMOS, signal treatment plays a huge role in final image quality,... the sensor is just one part of a complex system that should be evaluated as a whole only.

Cheers,
Bernard

[nuts and bolts]

Bernard

Thanks for your input.  I expected there would be stuff I missed on this forum, I am new to forums and work on a boat, so internet time is limited.  Thanks again

Sean