Many decisions go into purchasing a digital camera.
The physical size, shape, color and zooming capabilities may be a few of your determining factors. If you’re concerned about image quality, then you want to compare sensor sizes. The sensor in a digital camera is made up of thousands to millions of light-sensitive cells that capture information for your photographs. In general, the bigger the sensor, the better the image quality.
It’s similar to film. 35mm film has a 36-by-24mm image area. 120mm film, also known as the 2 1/4-inch-by-2 1/4-inch square format, has a 56-by-56mm image area, about four times that of 35mm film. If you really want quality, load up with sheets of 8-by-10-inch film at 228 by 254mm.
Equal-sized prints from these three format sizes would show that the larger film size, the better the image.
Larger digital camera sensors, like large film formats, lead to better image resolution, ability to hold finer detail in enlarged prints and better quality when shooting in low light with higher ISO settings.
Your basic entry-level point-and-shoot camera has a sensor size of 5.76 by 4.29 mm, or 1/2.5 inches. Note that some models use sensor measurements in millimeters while others use inches, but all camera models will list sensor size. This is good information to have to make side-by-side comparisons with other models you might be considering.
I’ve made a list of sensor sizes, all in millimeters, for some cameras I use along with some other models popular among amateurs and pros. All of these cameras have different functions and features that set them apart, but by comparing sensor size, you can get a good indication of which ones will offer better image quality.
It shouldn’t be a surprise that the larger the sensor size, the more expensive the camera.
• Canon S100: 7.6 by 5.7 mm
• Fuji X10: 8.8 by 6.6 mm
• Nikon V1: 13.2 by 8.8 mm
• Fuji X100 and Sony Nex 7: 23.6 by 15.8 mm
• Nikon D800 and Canon EOS 5D II: 36 by 4 mm (This is also known as a “full-frame” sensor because it is the same size as the 35mm film equivalent.)