Resolution

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Resolution

The resolution of a camera measures the amount of detail the camera’s images will pick up. In standard digital video, the resolution is measured in pixels. Our Camera's ability to display clear details, however, is a product of the 22x optical zoom and doesn't need the high resolution that a purely digital zoom camera would need.


A more old-fashioned way of looking at resolution involves looking at the lines of resolution. Analog transmission of a video signal is based on lines, and the TVL (TV lines) number represents how many lines can be resolved on a display (TV, VCR, etc.). Drawing a comparison between analog and digital measurements, the TVL will be approximately half the number of horizontal pixels. And, indeed, we see that the (H) pixels are 811 and the TVL measurement is 480.


480 TVL is about the same resolution you get from a VCR. Our camera doesn’t have a strong need for a high resolution because the image quality is already high. The quality and clarity of the image is brought to you by the 22x optical zoom. While standard digital video recording would simply crop and enlarge the image you wish to get a close-up on, ours will actually zoom in to bring you closer to the image, producing a much clearer image than could be achieved by simply raising the picture’s resolution.


Optical? Analog? Digital? What does this all mean?

Analog:

The principal feature of analog representations is that they are continuous. For example, clocks with hands are analog— the hands move continuously around the clock face. As the minute hand goes around, it not only touches the numbers 1 through 12, but also the infinite number of points in between. Similarly, our experience of the world, perceived in sight and sound, is analog. We perceive infinitely smooth gradations of light and shadow; infinitely smooth modulations of sound. Traditional (non-digital) video is analogue.


Digital:

In contrast to analog, digital representations consist of values measured at discrete intervals. Digital clocks go from one value to the next without displaying all intermediate values. Computers are digital machines employing a binary system, i.e., at their most basic level they can distinguish between just two values, 0 and 1 (off and on); there is no simple way to represent all the values in between, such as 0.25. All data that a computer processes must be digital, encoded as a series of zeroes and ones. Digital representations are approximations of analog events. They are useful because they are relatively easy to store and manipulate electronically.


Optical:

An optical sensor that turns the light coming through a digital camera lens into an electronic signal which can then be recorded onto tape is called a CCD (charge coupled device). The quality of video a digital video camera can produce depends on the amount of detail the CCD can detect. This detail, or resolution, is measured in pixels. The higher the number of pixels is, the cleaner and more detailed the video will be.


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