Core Electronics Forum

Low Light condition Light sensor

Hi I’ve been using a BH1750 https://core-electronics.com.au/light-sensor-bh1750.html and find its OK for general daytime monitoring, its less useful in low light conditions. About 30 mins or so from dusk its drops to 0 lux readings. I’m trying to capture artificial lighting - spotlights and the like but the BH1750 fails to register the light from them. Any ideas ro suggestions for a better option? BTW I’ll be connecting to a RPi.

Many thanks in advance,

Wayne

Hi Wayne,

Sorry to hear you’ve been having trouble with your sensor! While the DFRobot wiki page seems to show that it can be used for low light conditions like you say, it also mentions mounting a reflector on the sensor in order to magnify the light hitting it would be a good idea.

It does seem odd though that it can’t even pick up artificial lighting…

Keen to find out if you get anywhere with a reflector!
-James

I looked up the specifications on the chip used by DFRobot; I don’t think it is capable of doing what you want. It states LUX levels from 1 to 65535. Night time light falls to less than 1 LUX. You need something that works with levels less than 1 LUX.

Regards
Jim

Hi Jim,

Reading the datasheet, I agree, even in “high-resolution mode” it seems it’s resolution is far too coarse:


We should do some testing of our own I believe, but in the mean time I’ve marked the product for a review as the DFRobot resources do not correlate with the datasheet

-James