Jesper wrote:A computer magazine here (Computer X) published an article about ten megapixel myths. Here are the myths (which are, obviously, not true):
* More megapixels means better quality.
* Eight megapixels is twice the resolution of four megapixels.
* Digital lags behind analog photography.
* You need at least six megapixels to be able to print at A4 size (210 x 297 mm).
* A compact camera is as good as an SLR.
* The more megapixels, the less noise.
* An eight megapixel camera is better than a four megapixel camera.
* There's a demand for consumer cameras with more than eight megapixels.
* 23 megapixels is more than 5600 x 4100 pixels.
* For a 10 x 15 cm (4 x 6 inch) print you need at least two megapixels.
Read the article
, but it's in Dutch!
Can't read the article, but many of the statements are just blanket statements without the proper qualifiers. For example, more megapixels certainly, on its own, doesn't mean better quality. The obvious comparison would be the images from the 300D/Rebel compared to the Pro-1. Both are good, but the Rebel will give a much cleaner, lower-noise image. On the other hand, the 8.2 Mpixel 20D does outperform its 6.3 megapixel predecessor in most ways, even if only modestly.
Some are more obvious - more megapixels does not equate to less noise. In fact, if nothing other than pixel density changes, you could expect an increase in noise with more megapixels (of course, other advances come with newer cameras so no direct comparison can be made). And, a 2 megapixel image is approximately 1200 X 1800 pixels which gives you 300 ppi, which will give a great 4X6 print.
As for RAW and JPG, it depends a lot on what you're going to do with the image. An 8-bit JPG, if exposed well, will be identical to a converted RAW image. But, if you desire to tweak the exposure and/or white balance, you'll not have much room to play with the JPG. The other side of that coin is that RAW is time and space-consuming. So yes, as a blanket statement, you can't say RAW is better than JPG, but if the specific use calls for the increased flexibility, you would be better off using RAW.