On 8 Sep, 22:35, Owain wrote:
On 8 Sep, 21:58, Recyclist *wrote:

A photo-sensor to switch a light on?
Yes, it's a cupboard which is a bit gloomy with a door open and very
much more gloomy with the doors shut. * As long as you have daylight
or other lights on nearby, with suitable tweaking of the sensitivity
there is no reason it won't work.
So, how do you get the light to switch off?

You close the doors. The cupboard is in darkness. Note - the photocell
is inside the cupboard. The light is *outside* the cupboard shining in
(AIUI)

Owain

That, and it is on a timer.