question about security camera performance

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Can anybody direct me to some good information to compare camera
specifications ?  For example many cameras will give you a lux rating and
say it will work down to 1.0 lux light or 0.5 lux light, but I haven't been
able to discern what that means in the real world.  I've found the technical
definitions of lux, foot-candles, etc, but have a hard time seeing what that
means in the real world.  Will a 1.0 lux B&W camera show anything on a
moonlit night ?  Moonless night ?  Also how do you convert the lens size to
a magnification power or angular field of view ?  Things like that.

I would appreciate any pointers to info about camera performance and optics
for the embedded engineer layman.



Re: question about security camera performance

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You don't.  Those have nothing to do with each other.  The size of the
lense governs only the sensitivity (basically: the larger the front
hole, the more light your camera collects --> the more sensitive it'll
be).

Cameras don't have "magnifications", anyway.

As to what a Lux means:

http://www.wordiq.com/definition/Lux


--
Hans-Bernhard Broeker ( snipped-for-privacy@physik.rwth-aachen.de)
Even if all the snow were burnt, ashes would remain.

Re: question about security camera performance
On 22 Oct 2004 20:50:09 GMT, Hans-Bernhard Broeker

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The lens "size" is an indication of magnification as used in the
photographic world. a 50mm lens does not imply that the diameter of
the lense is 50mm. In the 35mm SLR world it implies a magnification of
x1. The F-stop of a lense gives an indication of the physical size.
i.e a 50mm lense with an F stop of 1.4 will have more light gathering
power than a 50mm lens with an F stop of 4.

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A camera is a sensor with an element to focus the image onto the
sensor. A CCD sensor alone is NOT a camera.

Regards
   Anton Erasmus


Re: question about security camera performance
snipped-for-privacy@amleth.demon.co.uk says...
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Many CCD cameras are sensitive to infrared.  You can make an extremely
bright illuminator using some IR LEDs that will be invisible to the
human eye.  Many "baby-cams" have them built-in.

--Gene

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