PeteCress 0 Posted August 11, 2012 This is just idle curiosity, but I keep wondering why all surveillance cams with IR seem to use visible vs invisible IR. I know invisible is possible bc I have a game camera that uses it. Seems to me like that little ring of glowing red dots is just screaming "Steal Me!" to every passing crackhead. What am I missing? Share this post Link to post Share on other sites
Soundy 1 Posted August 11, 2012 Camera sensors are sensitive to IR, which is why it works in the first place... however, the sensitivity drops off sharply not far into the IR range. The longer the wavelength, the less visible the LEDs, the less effective and efficient it is, unless you get into more specialized, and more expensive sensors. The longer-wavelength IR LEDs tend to cost more as well - not a big deal if you're talking about one or two in a remote... adds up fast if you're talking a couple dozen in a camera. Share this post Link to post Share on other sites
mike_va 0 Posted August 11, 2012 The other problem which is a PITA is that the new LED's high power surface mount even at 940nm give off a red glow... The old 5mm 940nm devices had a tighter spread on wavelength and were not visible. Share this post Link to post Share on other sites
stephanovich 0 Posted August 12, 2012 The other problem which is a PITA is that the new LED's high power surface mount even at 940nm give off a red glow. kinda defeats the whole point of 940nm doesn`t it ...I just love the 940nm I use Share this post Link to post Share on other sites
Soundy 1 Posted August 12, 2012 The other problem which is a PITA is that the new LED's high power surface mount even at 940nm give off a red glow. kinda defeats the whole point of 940nm doesn`t it .. Physics is a ***. Share this post Link to post Share on other sites
