Check out this post;
http://www.candlepowerforums.com/vb/showthread.php?t=291391
Like you stated, what you have is a photocell. All it is, is a resistor that changes with light input, nothing else, so it won't really do anything by itself unless you know what to do with it... As the most futile starting point, you should get a multimeter and meter the resistance in total darkness and sunny light so you know what you're dealing with.. In a device that's already set-up and ready to go, it might be easier (than the aforementioned post), but a photoresistor isn't the way to go... what you want to do is control the light output (current) depending on the ambient light.. Depending on the output of your flashlight you MIGHT be able to get a photo-transistor/diode/resistor to "plug and play" suit the circuit... It all depends on the numbers... Is there any way you could tap into the LED circuit of your flashlight and give me some voltage/current specs?? Without any serious damage?? Not from the battery contacts, I need the LED output itself... I need to know what is cruising through and across the led's themselves!
Honestly, It's a KICKASS idea... imagine a ultimate light, one that would dim to read a book, light up to illuminate a room, then explode with light once you're outside in total darkness. Like in the post i mentioned at the beginning, somebody mentioned using this in a caving situation... It is TOTALLY doable, and would rock major ***... Still, it's quite an undertaking... An "ultimate" version would take alot of technology, and at a minimum would require a user input for different modes or sensitivities..... I just don't think there's enough light reflected back to make a circuit like this work for every situation... Maybe caving, at most, but it's still going to end up with a bypass switch to get full brightness, i can just tell......
^ What happens when you want to shine your light at something close, and have it bright?? what happens when the light reflects off certain materials, glass/water/dirt?? Surely you'd have to revamp the design for specific intended uses; caving, home, outside, boating, even snow, rain or sand dunes could mess up the effect... also, a "home-made version" would probably just use 1 or possibly 2 "detectors"... An ideal light would have an omnipotent detector, that works regardless or orientation.. What about walking down a hallway or tight spaces?? Would you ALWAYS want to hold the light in a certain position so the ONE or 2 photoresistor(s) is aimed right??
I hate to say it, *again*, but something like this just REQUIRES a PIC and alot of knowledge.. You'd never meet the space requirements and have it useful in multiple situations.., unless you had a PIC, and a totally revamped light...
However, if you are driven, I am confident you/we could make something work, but I think it'd be limited in modes, for example; as a house light, 3 modes, (book/close up---smallroom/closet----big room/outside) or as an outside setup, 3 modes (map/close up----at feet/kinda close----far away/open space)... It's be really complicated and a large circuit to design something with a smooth response, in say -feet from target....
Am I making any sense??
. check out the latest Arc LS
