MegaPixel Myth

Some interesting articles on MegaPixels & what they mean.

David Pogue's Deconstructing the MegaPixel Myth

Ken Rockwell's MegaPixel Myth

TechLounge on MegaPixels

I just bought a Kodak EasyShare V1253 digicam that boasts 12 megapixels. This is higher than the vaunted Nikon D200 in the 10 megapixel range, one of the standard bearers of professionals in above and below water imaging.

But let's take a look at the actual size of the image capture device between the two cameras.

The Kodak V1253 lists the imager as 1/1.72. This is gobblegook for .172" Canon does the same thing and has about the same specs for their 12 mp pocket digicams. Nikons pocket digicams use the same bizarre sizing method.

.172" means if you divide an inch into a thousand parts, it is 172 of those. Expressed as a fraction, this is about 3/16" of an inch.

BUT, this figure is most likely on the diagonal, just like when they measure TV screens.

Pro camera specs don't use such bizarre spec listing protocols, so Nikon lists their Pro D200 imager size as .930" wide x .622" tall once converted from metric.

Expressed as a fraction of an inch, this is close to 1" wide x 5/8th" tall. This is HUGE compared to the .172" CCD imager, yet the D200 is about 2 megapixels less in production.

So, my friends, do not be fooled and buy a digicam solely on the basis of megapixels, check those imager sizes amongst all your other specification homework.

As an update, here is an accurate deconstruction of the ridiculous correlation of small consumer CCD sizing.


The designation given to toady's CCD sensors dates back to a set of standard sizes given to TV camera tubes in the 1950s. These sizes were typically 1/2", 2/3" etc. The size designation does not define the diagonal of the sensor area but rather the outer diameter of the long glass envelope of the tube. Engineers soon discovered that for various reasons the usable area of this imaging plane was approximately two thirds of the designated size. This designation has clearly stuck (although it should have been thrown out long ago). There appears to be no specific mathematical relationship between the diameter of the imaging circle and the sensor size, although it is always roughly two thirds.

On the camera's specifications sheet, it mentions that the CCD size is 1/1.172". Simple mathematics will give us the approximate proportions. 1 divided by 1.172 is 0.8532. One inch is 25.4 millimeters. so 1/1.172" is 21.6724 mm. Since the sensor diameter is roughly two thirds, the sensor diameter is approximately 14.4482 mm, and that makes the length and width of the sensor 11.5586 mm and 8.6689 mm respectively.

I find it best to compare Resolution, Size of the picture in camera, and How many pixels in total per picture based on setting! At the highest setting!