If you have mains voltage, or whatever you are powering the door with, you could attach a neon or led, and have it lit permanently (Behind the door).

Regards, bear..

Colin … if you use mains power, then why not try a mains door bell transformer …somewhere about 5 volts output … fit a switch if needed, on the secondary side, and feed this to a cycle headlamp … a small one normally powered by 3 x AAA batteries … they have about 3 LEDs for the light output … in the space where the batteries would normally live you could fit a resistor, 4 diodes in a bridge, and an electrolytic capacitor to smooth out the supply if it is an AC output … the lamp units normally fit on the pushbike handlebars with a clamp … this should be easy to cannibalise to accept a woodscrew and fasten the unit to the wall or woodwork … all the bits are fitted in a ready-made box … and no need to worry about batteries going flat.

martin R

When you say you've got a camera watching it, why didn't you just choose a camera with IR illumination? You don't say how it's viewed – is it USB, video or IP? But either way they aren't expensive these days. Given that the camera already has a power supply, this would avoid the need for additional batteries and power supplies.

Murray

Why not buy an camera IR emitter? If you are powering the PTZ, then you could split the power to the emitter and off you go.

Given that you have wifi there and also mains power, get yourself a wifi smart switch like the Sonoff S20. You can then use it to turn a light on and off from anywhere in the world (or your house) to illuminate the door. You can then view the door through the camera, then turn the light back off.

I've got a smart switch in the workshop (actually a TP-Link) that is scheduled to turn off every night at 11pm, regardless of whether it was ever turned on manually. This means I can't accidentally leave my equipment turned on overnight. With these devices, you can program scheduled events from your smart phone.

The TP-Link model I've got (HS110) is a slightly snazzier version (than the basic smart switch), that reports back the power consumption and energy useage.

These wifi enabled devices are becoming much more affordable. You can now buy a range of devices for remote ("smart&quot access and even make your own domestic alarm system, complete with cameras, sounders etc.

As ever, you need to be wary of buying mains gear directly from abroad. It almost looks as if the Itead (Sonoff) gear has proper safety approvals for Europe and they appear to be available from recognised UK outlets eg Amazon. However, some brands might present shock and fire risks, so there is a strong argument for sticking to reputable brands such as TP-Link if you want to play safe.

Murray

Worth trying to see if your camera detects IR. Many do – the filters aren't bullet proof. In the dark, point the sending end of a TV remote at the camera. If you can see it glowing when buttons are pressed the brightness will give you an idea about the camera's IR sensitivity – or not!

I like Neil's tritrium suggestion best. A small glowing light on a door would make me think it had an alarm fitted. And the light would show up well on camera when the door is closed.

Dave

I would use an old phone charger to power a 10 mm led ( with current limiting resistor fitted ) then use a magnet / reed switch combo ( same as what an alarm uses to detect an opened door or window ) to turn it on when the door is open . Power usage would be negligible and cheaper than buying batteries .

I voted for it! I'm going to get a blue one to scare the socks off a friend who's nervous about radioactivity. I'm going to mention Plutonium. With friends like me who needs enemies…

My plan is to turn a scary looking container up from some 38mm diameter steel and paint a red band on it. When the hefty lid's removed using a pair of sausage tongs he'll see thick walls surrounding a tiny glowing object. If it goes really well I'll be on News at Ten in handcuffs.