Considering a general acceptable fact, depth of field decreases, as image gets nearer to camera. This means that as focal point reaches closer to lens, achievable scope of depth of field ebbs. On other side, if image is far enough distant from camera, and for digital cameras, this must not be very far, depth of field approaches out to infinity. Another important point to be noted is that depth of field is proportional to lens opening.

Having discussed above important aspects of light and depth of field of a digital camera, it is clear that minute details make such great subjects whose knowledge becomes equally important for making appropriate use of fantastic device, digital camera! And digital camera, light and depth of field comes out to be such important factors that can make all difference if a photographer remains oblivious about this knowledge. A small factor thus can meal a big divergence!

Taking a look apart, it can be observed that quite a few digital cameras use CMOS (meaning complementary metal oxide semiconductor, a technology of manufacturing these microchips) technology based microchips as image sensors. The basic advantage is that CMOS sensors are appreciably cheaper and simpler to fabricate than CCDs. Another great advantage from CMOS sensors is that these take very less power compared to other technology, which adds up to fact as to their extensive use, and can thus even support implementation of additional circuitry on same chip like ADC, some control units etc. Thus it can be stated that CMOS technology based cameras are small, light, cheap and also energy efficient, yet at cost of some amount of image quality.

However common trend remains that all cameras of mega pixel range and higher up use CCD chips instead of CMOS. This is because of fact of picture quality only, leaving aside price differences.

This is basically fact about how digital cameras work! Having known this much difference would not come in photographing expertise of users, but it always feels a kind of satisfaction on understanding inner depths of a device that is so close to eyes!