Ambient light color sensor tips?

Using Arduino Sensors
1

Hi,

I would like my Arduino to be able to sense an average ambient color. RGB Color sensor TCS34725 works only for items put close enough to the sensor. ISL29125 look like it might do what I want. Do you have any other tips?

Basically I want to point the sensor the same way I am looking and I want it to tell me the average color of the scene the sensor can see. Looking towards a forest will give me an average green.

2

Camera + image processing software.
But that's out of reach of an Arduino. Teensy or so may work.

3

Create a pinhole camera. But the hole can be much bigger, which will blur the image a lot. The focal width and the diametre of the hole define the sector or the cone from which you gather light.

4

Thanks for the tips! I kinda hoped there would be some simple l2c sensor I could hook up to my Arduino, seems like ill have to do it an another way.

5

Unfortunately, no.

I'm also interested in the overall idea, primarily to measure PAR for growing plants. For that you basically need a spectrum analyser, and while those are readily available for sound, they're not available for light (I don't really know why, my best guess is light is too high frequency for sensors to create analog signals of, that can be frequency analysed).

Detecting whether you have light, is easy. Detecting what frequency of light you have exactly, is a whole different ballgame.

6

Maybe a Pixy?

7

wvmarle:
Detecting whether you have light, is easy. Detecting what frequency of light you have exactly, is a whole different ballgame.

You need a mirror to focus the light, a diffraction grating (maybe a CD would work), and a photodiode array. Light hits the grating and you get a rainbow coming off. That gets focused with the mirror onto the PDA in such a way that it covers the whole strip of photodiodes. Takes a bit of calibration to figure out which wavelengths each diode is seeing. Probably get a good lesson in instrumentational amplifiers in the process. I know I did.

I built a PDA based spectrophotometer one weekend as a rainy day project. It's not terribly difficult. But I used a low end PDA that probably isn't good enough for what you want to do. Better PDAs can be had if you got the money. I posted it on another forum but unfortunately all the pictures have disappeared from that post. So it's not very helpful.

I think the code to drive the PDA is even on my github still. Same name on github except a hyphen instead of underscore. Delta-G instead of Delta_G.