Easy Basic Photography
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Digital Camera Pixels and Megapixels
The word Pixel is a twist on the words "picture" and "element" combined. A pixel in digital photography is a single point
in a picture or image that we view. By itself, it is nothing more than a minute dot or square of color. A digital
photographic image consists of millions of these pixels or picture elements in different colors and different color
intensities. One million pixels equal a Megapixel.
Any discussion of digital camera pixels goes hand in hand with a discussion of the digital camera image sensor. Check
the tutorial Digital Camera Image Sensor for additional information about the function of pixels.
The pixels are created by light captured through the lens of the digital camera into a device called the camera image
sensor. The image sensor has millions of light capturing wells or cavities called photosites. Each of these photosites
have specific locations and are arranged in rows and columns similar to a spreadsheet. The information about the
qualities of the light captured in each of these photosites is recorded to the camera memory. When the information is
reproduced, the pixels are shown as continuous varying tones and colors that we view as the final image or "picture".
How many pixels do you need? The short answer is, more is better. Each pixel has information about the color and
intensity of the color at its location. The more information that is gathered as a whole and reproduced as an image, the
clearer and sharper the image will be. This image detail is also known as the image resolution. For example, a 10
megapixel camera should produce a better image than a 4 megapixel camera. However, there are other factors that
affect the image quality such as, but not limited to, sensor and pixel size, camera lens quality, and the overall quality of
the camera.
Pixel Size: The size of a pixel definitely affects the quality of the digital image. A larger pixel will contain more absorbed
light or photons during an exposure than a smaller pixel. This translates into more digital information being recorded
during the exposure which means the photographed scene will be reproduced with more accuracy. Digital Single Lens
Reflex cameras have larger sensors than Digital Compact cameras and therefore have the capacity to contain larger
pixel sizes. A 10 megapixel Digital Single Lens Reflex camera with its larger sensor and pixels size, will produce a
higher quality image than a 10 megapixel Digital Compact camera with its smaller pixels and sensor size.
Do not let this information discourage you if you are a Digital Compact camera owner or were thinking about
purchasing one. The quality of images in most Digital Compact cameras is excellent for the average user and the
larger pixel size in the Digital Single Lens reflex camera probably wouldn't be necessary in most cases. I suggest you
should get the most megapixels available in a camera that fits your desired camera style and budget. However, do not
become obsessed with the number of megapixels. For instance, you might be considering a particular camera you like
with lenses and other features that are perfect for your use, or style of photography. Do not forsake useful and desired
features in a quality 12 megapixel digital camera, to buy a lower quality digital camera just because it has 16
megapixels. Remember, the number of megapixels is not the only factor in determining image quality.
