Best surface for sensors

[lshea]

I have a question about the Adafruit TSL2591 high dynamic range digial light sensor- STEMMA QT. I am interested in using the sensors on surfaces that produce the highest differentiation between white and black. Does bright white paper work better than normal copy paper? Does black ink or black toner or marker or electrical tape produce the best extreme?

[adafruit_support_mike]

There are too many free variables to make general statements about different kinds of paper.

At the extremes, I’d say the highest contrast would probably come from retroreflective tape (the high-visibility stuff used on firefighter’s jackets and night/morning jogging suits) and Black 3.0 paint:

https://www.culturehustleusa.com/produc ... aint-150ml

The TSL2591 isn’t directional though. It sees the average of all light in front of it. You can make it more directional by putting it in a box with a hole in the front.. essentially making it the plate in a pinhole camera. You can also use lens syatems to focus on a specific region, which has gotten easier with the market for add-on lenses for cell phones.