How to find cheap light sensors

Many online vendors sell Photoresistor light sensors for $2 or $3 each.

I found a cheap source of them in my hometown. Go to a dollar store and find an auto “Nightlight”. Those are the small lights that plug into your wall socket and turn on automatically at night so your small children do not get afraid of the dark.

Only $1 each at the dollar store and contain a photo sensor. Remove it and use it in your own projects.

the electronic goldmine usually have a grab bag of different photo resistors for a few $$$

here (20 for 3$)

yes that is cheap. But a $50 min order + shipping and border crossing fees makes it not worth the effort for me.

oh well, I guess I'll have to wait until the US asks to join Canada.

Parlez-vous français?

bien sur

(that will be 35 bucks - US please) :-)

I'm on the other side of te atlantic, so i also only order from the states when i have more than a few things on the shopping list.

Better do it soon. Most of those photoresistors contain cadmium, don't meet RoHS act requirements, and are being replaced by other technology (for instance, the latest version of the Atmel Butterfly does not include the light sensor.) Phototransistors will probably show up in most of the things that just need to detect dark/notDark, but they're not nearly so linear and easy to use to gauge intensity levels.