An electronic digital camera works a lot like film camera in that light comes in through the lens and it is captured to develop a picture. The way the image is captured is what makes a digital camera totally different compared to a film camera. On a film camera, you press the shutter button which opens the shutter letting in the light. The light entering the lens is exposed to the film and results in chemical reactions on the film to create your photograph. In a digital camera the image is captured using an image sensor that converts the light rays into electronic signals which are then kept in a file inside buffer memory.
The light detector or image sensor is known as charged couple device (CCD) and it is comprised of individual light sensitive picture elements popularly known as pixels. Digital cameras tend to be measured in megapixels or millions of pixels. A camera having a 3000 x 2000 array of pixels within the image sensor would contain 6,000,000 pixels and is known as a 6 megapixel camera. When the light hits the CCD it breaks it down into the millions of pixels and measures the amount of light and color to generate a number for each pixel. Your digital picture is really a long string of numbers that is stored at a file in memory. The LCD screen on the back of the camera shows you the picture which the CCD is capturing.
Digital photographs have to be compressed or the file size would be enormous and fill up way too much memory. The most frequent compressed format is JPG which stands for Joint Photographic Experts Group. The higher the amount of photo information is kept the better the picture quality and the bigger the file. The more compressed the photo is, the lower the quality and the smaller the file size. The smaller file size makes for shorter load time plus you may store more photos in memory. One does sacrifice quality however.
The fact that digital images are stored digitally ensures they are easier to store, share and manipulate. When you open a photo inside an editor such as Photoshop, you’ll be able to change the quality of the photo by simply clicking on a setting. When you do this it changes the numbers which the pixels are storing to generate the effect. For example, if you need to make the picture 10% brighter, the image editor would change the pixel numbers by 10 percent to show increased light or brightness.
Some digital camera models have built-in effects and you may produce a photographic effect inside the camera right after you take the picture. Something you can′t do with film cameras.
Find out about the new Hybrid Cameras on the market and check out my lens on Hybrid Cameras too.