For my video surveillance project I needed special video camera to make video shots in the dark. One local company offered YOKO YK-3B41 or YK-3B43 video cameras. The body, lenses and IR emitting diodes are located in the same box. The box has IP65 class and the manager in that local company told, that it is waterproof.
Inside there is Sony CCD, 12 IR light emitting diodes. 12V external power supply is needed for this device. The diodes starts to glare only then when light situation is poor.
As digital photo camera is sensible to IR wavelength light, you can see how IR diodes glares in the dark. In fact, the diodes are a bit overloaded and you can see red light with bare eye. One interesting side effect from IR light is that you can see blood-vessels under the skin if camera is used in complete darkness and is quite near the human body. Normally vessels are invisible 🙂 .
Camera was recommended as watter proof, but maybe the particular one was defective or it was only advertising myth. I played with video camera for a while, holding it in my hand and suddenly the sharpness the video image disappeared. Short glance to the lenses solved the mystery- there was fog inside the camera body, against the lenses. Somehow, the human humidity managed to enter “waterproof” camera body. The only good thing is that the mist disappeared from it after some time.
Another bad side of this camera (and all other cameras with IR backlight near the lenses) is that all the dust floating near the lenses are reflecting IR light and whole image is full of “ghosts”.
And the last comment- this model of video device is using fixed objective lenses, so it is impossible to adjust sharpness of the image.
Conclusion: expensive toy. Usable only for general surveillance.
