With the continuous improvement in scientific field, every electronic/electrical instrument has started to become digitized. Using digital instruments makes our work easier. One such digitalization is for Cameras. However the cost of digital instrument still is a issue to worry.
While u go for a camera, the first issue of concern is the clarity and naturalness of the photograph. It is common for a human to slighly move his hand while clicking. Which will result in blur. At times the subject may be in motion while the picture is being taken. But nowadays the digital cameras have taken these factors into consideration and has tried to get a picture as if everything was actually standstill. But there are a few cameras that say that provide these features(esp SONY) but still have blurs in the photograph even when they are taken in stable position.
The next issue in the clarity is the resolution of the photographs. In photography this is better termed as Megapixel. The greater the megapixel quantity, bigger is the size and better the quality of the picture. so to get a good camera its better to choose a higher megapixel one.
Zoom is the feature that is provided in the consumer cameras where as the ordinary amatuer film cameras dont. There are basically two types of zoom. Digital Zoom and optical zoom.
the digital zoom is provided by the software and the optical zoom is provided by the lenses by changing the point of focus. The greater the zoom level, the closer the object is. U can take a photograph of a distant hill as if u were really close to it. the pictures taken in digital zoom will not be of good clarity and will contain grains or noise. some cameras provide digital zoom for still photogragh and might not provide the same for videos. It is otfen worth to get a camera that provides viceversa or for both. Th cons of zoom(both digital and optical) is that u would have sufficient brightness in the picture. to compromise this most digital cameras provide a setting called Exposure Value(EV) setting. This feature can be used to improve the brightness before the picture is being taken.
The next issue is the focussing capability of the cameras. Most cameras have autofocus. Ie it identifies the object and tried to make it very clear to be taken in the photograph. Nowadays a few cameras can recognize upto 12 faces and focus on these 12 faces. Also the most important factor is the time taken to focus the object. The cameras also try to find the different modes and thereby adjust its setting to take the best photograph. some common modes are portrait, landscape, night mode, sport. The zoom feature literally becomes useless in most cameras when pictures are taken at night. but some cameras does have enough sensitivity to take good pictures at low light.
You can get the display of the photograph on the LCD screen. usually these screens are inbetween 2" and 2.5". the greater the size of the display, the greater is the quality of the picture u can view before and after u take the picture and also higher is the power usage. So its better to go for optimal displays. A few cameras also provide the facility to switch off the display to conserve power.
All digital cameras have memory to store the photo or video. There are various types of memory cards available and each type of camera support different type of memory cards. the internal memory can be used to store a few photos.
The last but not the least is the power consumber by the cameras. usually digital cameras consume more power than normal film cameras. The type of power source is also under consideration. Many cameras allow alkaline and other rechargable batteries. And many cameras also work on adaptors. The lower the power usage the longer is the camera usage and the more picture u can take. When u make long tours, Your cameras might become useless because of the usage.