Video camera are amongst the most frequently used tools of the amateur paranormal investigator, many use one of the Sony models that offer the ability to record images in zero visible light conditions - the ''NightShot' mode. This makes us of the inherent ability of an imaging chip's ability to see Infra Red (IR) light almost as well as the visible portion of the light spectrum.
First StepsAll camcorders made within the last 10 years use an imaging chip - most in the form of a CCD type device and so the first step for the reader should be to go back to the previous sections dealing with digital still cameras and re-read it. In effect, all camcorders, regardless of whether they use analogue or digital tape and DVD or even a hard disc are just a still camera that takes a continuous series of pictures. However, there are some subtle differences in the chips and the way the image information is dealt with that needs to be considered.
The Next StepsImage chips in digital still cameras are used to produce a picture that may be viewed on a computer, a TV or printed in a range of sizes. An image chip in a camcorder only has to produce a high quality TV moving image. Actually, it is best to describe the final product as a series of still images as in the UK a television picture is actually a series of 25 still frames per second, so the similarities in the initial stage of the image making process are easy to see and indeed most camcorders also have the ability to act as digital still cameras too - recording the still images to either the main recording media (tape etc) or an additional memory card.
Camcorders do not need to have a lot of pixels, with some recent exceptions most still use less than 1 Mega-pixel. Some makers offer larger pixel numbers - although the specifications need to be carefully looked at prior to making any purchase, some Sony models have '3-Mega pixels' boldly displayed on the bodies of some camcorders, the figure refers to the total number of pixels that are available for use in taking digital stills. The number of used for the video images is 2 Mega-pixels.
The reasons that camcorders do not need so many pixels per chip is primarily because TV screens cannot display very high resolution pictures - even High Definition (HD) is still much lower than a printed picture requires. For a number of years Broadcast resolution video cameras have used 3 chips to improve maximise the quality. This allows each chip to be optimised for a single primary light colour i.e. Red, Green and Blue (RGB). This reduces colour smearing and makes the final pictures appear sharper and better defined. 3 chips are now a feature of many consumer camcorders although their advantage is largely lost at lower light levels and also it is rare to find 'Night vision' abilities on such models, designed mainly to optimise daylight use or use with powerful video lights.
Large image chips do have some advantages though in video photography. As with digital still cameras they usually perform better in low light situations as there is a larger available light gathering area. Unfortunately it's never that simple. Most camcorder manufacturers use developments in image chip design to squeeze more pixels into a physically small design. Some recent 1 mega-pixel designs - even ones with IR Night vision perform markedly worse than previous models under the same conditions - the smaller individual pixels mean less light sensitivity!
A word of caution about these image stabilisation systems regardless of type. If you are using the camcorder mounted to a tripod or other form of solid support - even a table top then turn off the stabiliser. If left on, it can cause the image to appear to move - both sideways and also up and down, as the stabiliser 'hunts'. This can and has caused many unwary investigators to believe that either their camera was being 'played with' by some unseen force or that some other strange paranormal effect was happening.
Another feature of many camcorders is some form of Image Stabilisation, in the top end models this is done optically by a moving lens or prism system, in most consumer models this is done electronically however. The image chip is made with more pixels than are needed to make-up the final picture. The extra pixels are used to reduce the effects of movement of the camera when hand holding. This is an effective system particularly when one is using the camcorder at higher zoom lengths. No stabilisation method will remove all camera motion but having this ability can make a big difference to the final picture quality.