dSLR tech. links needed

[felix_ing]

Hi there,

 

Could someone be kind enough to forward me technical information in

detail on:

-relationship between sensor size and MP (read that more MP doesn't

equal better pix unless senor's bigger?)

-relationship between ISO and noise

 

(I need very technical info so that I can understand more of digital

cameras)

 

Thanks.

 

Cheers

[ulrich_brandl]

At a given sensor size, an increase of pixel count makes the pixels smaller, increasing resolution. Current lenses, at least the best ones, yield higher resolutions than the current sensors have. A smaller pixel, however, catches less light during a shot than a bigger pixel. The light generates the signal you want, the signal amplitude is therefore higher with bigger sensors. The visible noise in your image depends on the ratio of this signal and the sensor noise. Therefore bigger pixels tend to give a better signal-to-noise ratio. High ISO settings work like an amplifier and thus amplify the noise too. But this all is true only if you compare sensors at the same level of technology.

 

You can find more technical info under:

 

http://www.photo.net/equipment/digital/basics/

 

Ulrich

[mark u]

There's a lot of good info here:

 

http://www.kodak.com/global/en/digital/ccd/products/fullframe/fullframeFamilyPublications.jhtml?id=0.1.4.8.10&lc=en

 

Of course, you aren't going to get something that really tells the whole story for a particular comparison between cameras without looking at reviews such as those at dpreview, which provides some measurement of actual noise levels on reviewed cameras.