cachecreekcctv 0 Posted January 3, 2007 Just a quick question to ask those on this forum who are more knowledgable in the area...what actually is the "filter" which is mechanically/electrically moved out of the way of the CCD in "True" day/night cameras? Is it an IR glass filter of a certain NM range? I have seen them up close, but no one I have met can actually tell me what they actually are. OOPS!! 2nd part of question: What is its' purpose? Thanks!! Share this post Link to post Share on other sites
galen 0 Posted January 3, 2007 I'm probably wrong on this but I think a mechanical cut filter is when the photocell switches from day to night. It does it mechanically and instantly. Not like some that linger and you have a degrading in the image while the other way of switching is done which can take some time. Just a better grade of camera. Share this post Link to post Share on other sites
CollinR 0 Posted January 3, 2007 I don't know the specs but yes it is a visable light bandpass filter that blocks UV and IR light from the CCD. In night mode the filter (or mirror) is moved to allow all light through. This is only on color cameras, BW cameras don't need a filter as they don't reproduce colors that would be scewed by the other light frequences our eyes can't see. If you don't want to pay for a REAL day/night camera just go with a quality BW model. Share this post Link to post Share on other sites
Metal Shaper Man 0 Posted January 3, 2007 While the human eye can only register light between the blue and red spectrum, a color camera's image sensor can detect more. The image sensor can sense long-wave infrared radiation and thus "see" infrared light. Allowing infrared to hit the image sensor during daylight, however, will distort colors as humans see them. This is why color cameras are equipped with an IR-cut filter -- an optical piece of glass that is placed between the lens and the image sensor -- to remove IR light and to render color images that humans are used to. As illumination is reduced and the image darkens, the IR-cut filter in a day & night camera can be removed automatically to enable the camera to make use of IR light so that it can "see" even in a very dark environment. To avoid color distortions, the camera often switches to black and white mode, and is thus able to generate high quality black and white images. Share this post Link to post Share on other sites
galen 0 Posted January 3, 2007 As I thought, I wasn't even close. Share this post Link to post Share on other sites
