How Important Is Color For You At Night?

Typically, users give up color imaging at night to compensate for low light levels, either by using D/N cameras or IR.

How often do you find this as a problem - i.e., giving up color at night?


I have often felt the need for colour under low light conditions, specially when there is a need to positively identify trouble makers in dimly lit crowded bars and similar scenarios. So perhaps one could say that while it is desirable most of the time, it becomes essential only about 10% of the time.

Hello, For an ANPR project, we need to see and detect the color of the number plates at nights.

It is easy to detect the color at day time. But at night the cameras are switching to B/W mode and we are using IR illumination. Any advice?

If you need to detect color at night, you'll need to add white light illumination and keep in color mode. The same manufacturers of IR illuminators typically make white light units. See our test of white light illuminators.

Color can be important for police departments in a state, local or municipal settings or a public safety department at a university. For example, having a color image of a potential suspect or suspect vehicle adds significant value when compared to only having a B/W image. It is also helpful when a victim of a crime describes the clothing or vehicle color and the investigator is able to review archived video to locate the suspect or suspect vehicle on another part of the campus/city.

Mark, good feedback. Thanks!

Is it important enough to not allow night mode and/or IR illumination?

Dear John,

Could you give comments for below image?

Thanks.

1. It's using IR illuminator at night, but it's color. Does it mean the camera remove IR cut filter and use FW to keep color, not B/W.

2 For the case to use IR illuminator at night, is it possible to see license plate with red characters? Please check below image, it shows it cannot see plate information that with red characters. Any comments here?

For image #1, if you are using IR at night and the video is in color, either one of two things is happening:

  • The cut filter is blocking IR light and the illuminator is making no difference at all. This is easy enough to check, just toggle the power to the IR illuminator.
  • There is no IR cut filter and the IR light is increasing illumination for the color image.

As for image #2, I am not sure as I have never seen any license plates with red characters :)

"I am not sure as I have never seen any license plates with red characters :)"

Certain Massachusetts plates use red characters.

IME, the requirement for color at night is somewhat related to how the video is used.

People doing passive recording with a low threat level don't seem to have as much use for color at night.

People using some kind of active reponse (eg: video monitoring where police/guards can be dispatched in real time) have less use for color at night.

However, people wanting to record "evidence" at night to use as followup/investigation video seem to have a much higher interest in full color night time video.

At some point in the 1950's, some Westinghouse guy was talking to an RCA guy and asked "How important is color TV anyway?"

Dear Sir,

Do you have comments for this product?

IR camera from Nanolux declaim their product can see color with the infrared illuminator.

Thanks.

This is the license plate of taxi in my country. Using IR with this plate we cannot see any information.

(1) For license plate color issue: Can you see plates with black characters? Can you share a picture of them?

My theory of why red is likely to be more of a problem is that the luminosity contrast is lower for red on white than for black on white (here's an online ratio analyzer tool). Black on white scores the max 21. Red on white scores a far more modest 4:1 (you need to enter hex codes for each color - here's a directory of them).

It's likely harder to 'see' red on white than black on white.

(2) Thanks for sharing the Nanolux video. I couldn't find any significant new developments in the 2 years following that video's release. I did find Nanonlux's website that does look to be actively maintained.

That said, the demonstration in the video is really not that impressive. Here's a screencap of what they claim for color with no light:

If anyone knows more about Nanolux, I'd be interested to hear.

Also, have you tried turning the camera into b&w mode to see if that makes a difference seeing the license plate characters?

Please check the plate with black on white.


Thanks.

Thanks for the follow. Good to see the difference between black and red plate characters. I am going to stick with my guess that it's the lower luminosity contrast for the red characters. Anyone have any other ideas?

AXIS Lightfinder actual footage [EDITED to reference real IPVM test results]