An Insider's View at How Your Digital Camera Works

You may have already taken thousands of digital photos through your cheap, mid-range, or expensive digital camera. But you likely have almost no idea of exactly what happens when you do; instead, you're usually just thrilled if the great shot you took actually comes out looking halfway decent by the time you transfer the photo into your computer or take its Flash storage disk (the tiny card found within many cameras that can be removed) and plug it directly into your photo printer without having to diddle with your computer at all.

But for those with a thirst for knowledge, and an appreciation that different cameras do offer some real variations in how they operate and actually handle your image, understand that the process boils down to a certain number of essential steps. With this in mind, and considering there are all types of digital cameras with many differing features, let's look at a basic rundown of the steps that occur in the operation of a digital camera once you choose to take a picture, aim, make adjustments to focus or flash, as needed, and click the snap button called the shutter release:

1. The digital camera tries to achieve the best focus possible.
2. It takes a reading of available light then sets the aperture and shutter speed accordingly.
3. The camera's sensor resets itself. The proposed image may pass through an optical pre-filter before the sensor gets it.
4. Once reset, the sensor is exposed to light and builds up an electrical charge until the shutter closes again.
5. The converter (ADC) takes a quick measurement of the electrical charge produced in Step 4.
6. The converter then begins to produce a digital signal reproducing the values of each pixel of the electrical charge it examined in Step 5.
7. The camera's microprocessor begins to interpolate the data and apply color in the depth it believes is an accurate representation of the image you shot.
8. If the camera has an LCD, the image may be viewable at this time.
9. The image is compressed using the desired compression format (either one you pre-selected or what is created by default) by the microprocessor.
10. The image is stored to the storage media.
11. The image is transferred from the storage media (or directly from the camera's built-in memory) either to the PC or directly to a printer.
12. If transferred to the PC, the image is available for direct manipulation either through the software included with the digital camera or any other applications that support its use like Microsoft Office or Paintshop Pro.