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which wavelength infra red emitting LED's for camera

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You want an LED with a wavelength as close to visible as possible, such as 880nm or 890nm. Anything shorter and it may be slightly visible to the eye.
 
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Sony's first "night view" camera caused trouble because it could see the frequencies of "heat" and therefore looked through clothing.
People's "hot zones" were clearly visible.
 
Sony's first "night view" camera caused trouble because it could see the frequencies of "heat" and therefore looked through clothing.
People's "hot zones" were clearly visible.
Do you have pictures of that?

I believe that's mostly an urban myth, since the IR radiation from the body does not penetrate clothing to any significant amount. It's the temperature of the clothing that you see. I worked on a military FLIR system which operated in the the IR region around 10 microns which is most sensitive to objects near room temperature, and a view of a person only showed their clothing and exposed skin temperature. The clothing was, of course, warmer where it directly contacted the body, but no details beneath the clothing were visible.

One interesting observation was that you could see the inside of a person's nostrils get lighter and darker as the person breathed in and out.
 
Do you have pictures of that?

I believe that's mostly an urban myth, since the IR radiation from the body does not penetrate clothing to any significant amount. It's the temperature of the clothing that you see. I worked on a military FLIR system which operated in the the IR region around 10 microns which is most sensitive to objects near room temperature, and a view of a person only showed their clothing and exposed skin temperature. The clothing was, of course, warmer where it directly contacted the body, but no details beneath the clothing were visible.

One interesting observation was that you could see the inside of a person's nostrils get lighter and darker as the person breathed in and out.

Actually, from what I remember, it had to do with people wearing certain kinds of clothing (mainly white and fairly thin) that allowed ambient IR light to pass thru, rebound off the body, then back out to the camera; the CCD may have been sensitive in that region, but I believe many CCDs have the same sensitivity profile, but most cameras have an IR filter in between the sensor and the lens. Sony's camera allowed you to go into "night mode" which disengaged this filter. Some cameras today have such a filter, cheap cameras typically don't.
 
The clothing that the Sony camera looked through was extremely thin bathing suits. Maybe the kind of cloth that allows the wearer to still get a suntan while wearing it.
My new eye lenses after cataracts surgery see thru bathing suits. (smilie)
 
The clothing that the Sony camera looked through was extremely thin bathing suits. Maybe the kind of cloth that allows the wearer to still get a suntan while wearing it.
My new eye lenses after cataracts surgery see thru bathing suits. (smilie)

LOL - that's funny! Although I expect you probably wish you had that without needing the cataract surgery...

Regardless, it must be interesting; I take it these lenses replaced your natural lenses (IOW, they aren't contacts, but artificial lenses)? Is it something about our natural lenses that block IR, vs your new lenses, I wonder...?
 
The new lenses inside my eyes are plastic with UV protection so I don't need sun glasses. Very sophisticated tests allowed the manufacturing of the lenses to make my distant focussing absolutely perfect so I can see the details on pretty young ladies very far away. Yum.
The close-up vision is the same as my original lenses so I use the same reading glasses I had before.

For a few thousand dollars more I was offered synthetic lenses that have adjustable focussing for near and far. But they are poor at night and sometimes get "stuck". I am very happy with my new lenses.
 
The new lenses inside my eyes are plastic with UV protection so I don't need sun glasses. Very sophisticated tests allowed the manufacturing of the lenses to make my distant focussing absolutely perfect so I can see the details on pretty young ladies very far away. Yum.
The close-up vision is the same as my original lenses so I use the same reading glasses I had before.

For a few thousand dollars more I was offered synthetic lenses that have adjustable focussing for near and far. But they are poor at night and sometimes get "stuck". I am very happy with my new lenses.

Did you have to go to the States to get the implants? The anti-Obama crowd down here would have us believe the Canadians have the worst health care in the world (because it is government run) :D
 
Hes not only infallable now hes got xray vision . Has this man no limits ?
 
Did you have to go to the States to get the implants? The anti-Obama crowd down here would have us believe the Canadians have the worst health care in the world (because it is government run) :D
Canadians have excellent health care. It is mostly paid by income taxes.
I just came back from another 6-months checkup with my local eye surgeon in his huge eye clinic in my city here in Canada. The eye clinic has the latest and best test equipment for analysing eye problems. The Canadian government pays for my visits but they pay only for the oldest and most basic lenses that are huge so the eyes take a long time to heal, and they give poor night vision. I got the latest improved lenses plus surgery to correct astigmatism so I paid about $1000 for each eye and my government paid about $500 for each eye. I couldn't claim the $2000 as a deduction on my income tax because I am retired and don't pay income tax any more. They pay me (old age pension).
 
Canadians have excellent health care. ...

I know this for a fact. My wife is Canadian, so we talk to her siblings and extended family about it. The Sarah Palin and her Tea Party buddies spread lies about health care in other countries in order to help their buddies who run the US Health Care System.
 
Well ur pretty lucky to be there I suppose . If u were in Australia you could at best claim an offset deduction for medical expenses if u did have an income to claim it against and that would be 20% of the amount over $1500 so u might get $100 on that sort of medical expense here but to top it off if u had medical insurance and they paid u say $500 you would get nothing . Now the really Government greedy bit is atm eye surgery of that kind does not even qualify as medical expenses here.


Geez when I was a kid of 5 my parents were going on in the boat to Canada and unfortunately were talked into getting off in Sydney instead. What a blow , I too might have had Xray vision and superhuman electrical construction powers. Just a small flip of the cards of fate ehh
 
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