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Camera
Sensitivity i.e. LUX:
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Another item of general confusion lies in the specifications relating to the
sensitivity of a camera to light.
This is normally specified as a number in a measurement called LUX. Now
we are not trying to get specific and learn everything about light, but
basically a camera's function is to see, and like your eyes, it has sensitivity.
A camera can't see in the dark, but then how does one specify how dark is dark?
Well that's where LUX comes in. It is a number that relates to how
sensitive a camera is, or if you will, how well it sees in the dark.
So, like in golf, here the lower the number the better the camera can see.
Or in other words the more sensitive it is to a lack of light. A 40
LUX camera is not as "good" as a 10 LUX camera, nor as
"good" as a 5 LUX camera, nor as a 1 LUX camera nor as
"good" as a 0.1 LUX camera. Of course to make it
more confusing the numbers are different for a black/white camera versus a color
camera. So first of all, don't compare black and white cameras to color
ones. Keep you comparisons as oranges to oranges and apples to apples.
So if you are looking for example at a camera that's rated at 10 LUX
and one that's rated at 5 LUX. The 5 LUX camera is a technically superior
camera, and one would normally expect to pay more for it, than the 10 LUX unit.
But as always that's not the end of the story. You do not use a camera
without a light. There is currently no measurement in common usage that
combines the camera sensitivity and the amount of light output to make it simple
to compare.
All camera manufacturers provide lights with their camera's. One
assumes that they do their due diligence and provide sufficient light so that
their camera will provide a proper picture, based on the type of camera they
use. Just because the specifications say one camera uses a 5 watt bulb
while another uses a 12 watt or a 20 watt or 50 watts of power, you are not
going to know whether that is necessary or not. It all depends what type
of pipe (material), whether it's clean or not, what size, etc.
As in any thing, the more you get the more you pay for it. Few things
are free. The buyer needs to know what they are generally going to run
into, and do they want to pay the price for something that will do almost
anything, or pay a reasonable price to cover 95% of what they will run into.
So look at the end product, a view in a pipe on a video cassette. That's
what your video camera provides.
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