Megapixel BS
If you were considering buying a new digital camera (and as a trannie this may be more often than joe public) you would more than likely go for a camera with a higher pixel count - as in, “Well, more pixels means better quality, yeah?”.
Wrong, wrong wrong. The marketing guys are selling the consumer a pup.
The marketing/advertising machine is using this as the major selling point in the compact digital market… and it’s misleading.
This is what it’s really like. The size of the sensor in the camera is going to have the biggest influence on picture quality in conjunction with the number of pixels in the sensor.
So if you take a compact digital, the sensor size could be as low as 5 x 4 mm. Now smaller sensors are cheaper and also with a smaller size camera it could make sense to use a smaller sensor.
So what happens when the manufacturer ups the pixel count from say 6mp to 8mp? Assuming the sensor size stays the same, the manufacturer crams more pixels onto the sensor; this means each light gathering pixel covers a smaller area.
And what does this mean? Less light capture through each pixel means reduced clarity and detail through greater digital “noise”. Now, the manufacturers can increase the digital “noise reduction” so the picture appears less pixelated, but this in turn softens the image providing less detail.
I’ve been toying with the idea of buying a Canon Powershot S5 IS because it has a 36-432mm lens - no additional lens to buy and no lens changes. Also, it’s significantly smaller than a DSLR.
The S5 has 8 megapixels as opposed to its predecessor the S3 which has 6. And this is where the principles I’ve been talking about can be illustrated very nicely.
Both cameras have the same size sensor (5.76 x 4.29 mm). Now take a look at the DP Review comparisons of image quality between the two models (new Window). The S5 image has greater digital noise. Just take a look at the vodka label comparison. Canon could have applied more noise reduction to the S5, but for various considered reasons have chosen not to.
The real answer to better quality images (all other things being equal) is to buy a camera with a bigger sensor. The bad news is to do this you’re probably looking at moving up to a DSLR - more expense, bigger/heavier to lug around, won’t fit in your handbag. Although you could change to carrying a carpet bag. ;)
The Nikon D40X DSLR has a sensor size of 23.7 x 15.6 mm as does the D80. And this is where you’ll get better quality images.
I know image quality may not be everything, but it just winds me up that marketers conceal this sort of information. Grrr!
Anyway, hope this helps and if you want to check out sensor sizes for a camera you may be considering buying then you can go to the model on www.dpreview.com (new window) and look it up under the specifications. I’d also suggest viewing the image comparisons under the full review, too.
That feels better!