so, something I had thought about for some time, but got new inspiration from reading Gina's all sky camera revisited thread, I decided I'd have a go at re-purposing one of the mini IP CCTV units I have laying around. It's a tiny mini cube with Sony IMX291 starvis sensor with WiFi and micro-SD capabiity and HikVision compatible, sourced from AliExpress a year or more ago. I had a few of these but replaced now with Annke HikVision cube types for the main CCTV system.
I will say that these mini cams are not weatherproof so I'd need some means of housing it if I want it aiming up at the sky and that's one reason I'd not got around to it so far. I do have one of these outside as a hedgehog cam, under a makeshift rain shield (an old ready meal container lol) and looking downward, all I did with that one was to cover any ingress points with silicone dielectric grease and 6 months down the road its still working great 🙂
So, how to test this sky cam idea. Well I purchased a dummy CCTV dome off ebay for a couple £ with the plan to install one of these mini cubes into it which has a 2.8mm starlight lens with IRcut filter afixed (no auto IRcut in these tiny cams). Didn't think to take any piccies as I did this, but easy to figure out. I used a metal bracket under one of the securing screws inside so the camera is held central and coiled the cables under it in the housing. Hole drilled in the lower section to feed the LAN cable in and then dielectric grease in the connectors just in case. Add a silica gel pack and duct tape over the hole, then clear RTV around the clear dome and the top plate and there you have it, a cheapo test rig...
Now I will say that the dummy dome is pretty poor optically, its not nicely smooth so there are ripples in the view and more so at the very top of the dome. But this is a test rig to see if this might work. Wasn't expecting something fantastic at that price, my expectations are low in terms of this "project" at this stage 🙂
The other issues I have to deal with are:
A large oak tree that will obscure the view to the SW and could well add a sap drip issue over time;
IR lighting for the security CCTV setup, can't shift those either so need to try shielding some of the impact to the sky image;
Camera limitations: 1/25s slowest exposure, for example
The garden is reasonably dark so in theory this may work ok, unless folk turn their garden floodlights on of course, time will tell...