how to use this infrared for surveilance hot spot

[magfurr...@gmail.com]

i want to ask, how to use this infrared for surveilance hot spot ?

[Chris Fastie]

Near infrared can be used for surveillance at night if there is a source of light that is only near infrared. People will not know the scene is illuminated by near infrared light but they will be visible to the camera. The source must be one that does not produce any visible light.

[magfurr...@gmail.com]

how to make the camera, just plug the ND filters ?
if i make with like Kogan camera, so i just pull the infrared filter from kogan lens, and i change with ND filter ?

thx, regards from Indonesia

[Chris Fastie]

Yes, the infrared block filter (IR cut filter) must be removed. There is no need to replace it with anything unless the photos are not focused. Then you might need clear glass to replace the filter.

[Chris Fastie]

A colored filter is required if the camera is to be used as a single camera plant health camera. A colored filter is not required for night time surveillance. The filter could reduce the effectiveness for surveillance by absorbing some of the NIR you want and also might reduce the crispness of the images. Clear glass of the same thickness as the replaced IR filter is to maintain the optical characteristics. It is not always required.

On Wed, Nov 11, 2015 at 1:07 AM, magfur ramdhani wrote:

If i look in the public lab,, the camera lens was plugged with NGB filter ?
Why use clear.glass to replaced the filter ?

Thx