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Re: IR Illuminators



Thanks, Robert!

"Robert L Bass" <no-sales-spam@bassburglaralarms> wrote in message
news:wISdnSiJwKe03PXbnZ2dnUVZ_gudnZ2d@xxxxxxxxxxxxxx
>> I have several day/night cameras, some really cheap,
>> one is somewhat expensive.  They work great.  But I
>> also have some very expensive high end cameras,
>> such as the Sensormatic Speeddome Ultra VII, and
>> the Axis 213 which are not day/night, at least not
>> automatic day/night.  These are the ones I need the
>> extra illumination for.  What would I need illumination
>> for on cams that already have day/night?
>
> Day/Night usually means (among other things) that the
> camera is equipped with a IR filter that disengages during
> the night.  The IR filter's purpose is to prevent IR light
> which is abundant in daylight from overloading the imaging
> sensor.  Without IR filtering the image would be washed
> out by all that IR light because the sensor sees it almost
> as well as it does visible spectrum light.  At night, however,
> there is very little natural IR light or visible light.  By
> removing IR filtering at night the camera can see objects
> (they look black and white) which would not be viewable
> due to the lack of visible light if you provide auxiliary IR
> illumination.
>
> IR illuminators are like visible light sources as far as the
> camera is concerned.  The more IR light the easier it is
> for the camera to see when there's little or no visible light
> available.  The problem with non-day/night cameras with
> IR filters is they get no visible light at night AND their
> fixed filters block IR.
>
>> I bought an IR illuminator on ebay thinking that I could
>> use it with the Speeddome Ultra VII inside my house so
>> that my daughter could not sneak back to her room
>> after being out half the night, but I can't see squat
>> because it's so dark.  It has 48 LEDs, but doesn't
>> illuminate worth a damn with that camera.  I tell the
>> seller, he says "you need low lux camera to take
>> advantage". That's like giving Dolly Parton a boob job
>> if you ask me.
>
> Heh, heh, heh...  An apt comparison.  :^)
>
> The seller is not giving you an adequate explanation,
> possibly because he doesn't really understand it himself.
> How far is the illuminator from the subject (in this case
> your daughter)?  It's possible the IR light isn't bright
> enough.  It's also possible (though I'm not certain without
> looking at the spec sheet) that the camera is not set for
> day/night operation.  If that is the case, a filter might
> be blocking the IR.  I'm not expert on that camera so I
> can't say for sure.
>
> --
>
> Regards,
> Robert L Bass
>
> =============================>
> Bass Home Electronics
> 941-925-8650
> 4883 Fallcrest Circle
> Sarasota · Florida · 34233
> http://www.bassburglaralarms.com
> =============================>




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