Cameras in mobile phones are well past being a low-grade gimmick. The quality of camera phone images has increased significantly, and the sheer convenience makes cameras an indispensable feature in mobile phones today.
2. Image sensors and the megapixel myth
3. Features to look for
|4. Issues and pitfalls
6. 5-megapixel camera phone showdown
Image sensors and the megapixel myth
Megapixels is the word on the lips of the marketing folks who represent imaging technology the world over. The number of megapixels just keeps getting bigger, and these numbers are commonly misinterpreted as an indicator of the quality of the images the cameras can produce. In camera phones, while most are still either 1.3 or 2-megapixel models, we are starting to see 3-megapixel and even 5-megapixel. This is great, right? Because bigger is better? Not necessarily.
Megapixel refer to the total number of pixels collected by the image sensor during an exposure. It's a measurement that, amongst other things, defines the potential maximum size of the final image. The problem is that as the pixel count increases, the size of the image sensor in camera phones remains the same -- it has to, to maintain the overall size of the handsets. This means the pixel size gets smaller to accommodate more pixels on the image sensor, and can result is an increase in noise; which appears in your images as "fuzziness".
The most commonly used image sensor in camera phones is known as a CMOS (Complementary metal-oxide-semiconductor) chip. You may have heard of CCD (charge-coupled device) chips used in digital cameras and camcorders, and in simple terms CMOS chips are similar in application. The main advantages of CMOS over CCD are size, cost and speed of processing, all of which make them a better option for camera phones. To date, the downside has been increased image noise, however, as the technology improves so does the quality of the images produced. For further detail be sure to read More megapixels, better photos: Fact or fiction?; an excellent look at the megapixel question that focuses on digital cameras, but with information that is also pertinent to a discussion about camera phones.
The quality of image sensors varies depending on the manufacturer. In our reviews we have seen 2- and 3-megapixel camera phones outperform the 5-megapixel shooters from their competition. The better camera phones will incorporate better image sensors in conjunction with higher quality lenses and flashes.
When shopping for a camera phone you'll notice that the more expensive models will have the larger megapixel counts. Just remember not to make your decision because it's bigger, try and test the camera to make sure it's better.