Allsky camera build

As an astrophotographer I’m always keeping an eye on the sky to see whats going on. But it’s hard, if not impossible, to constantly keep an eye out for Northern Lights, meteors or just knowing if the sky is clear or not. For several years I’ve had an idea of building an allsky camera that always keeps an eye on the sky for me, but I never got around to build one until now.

I started the build project in late August by ordering the camera I’ve found suited my needs the best, a ZWO ASI178MC. The camera arrived in mid September and since then I’ve been building and testing my ideas step by step, and now one month later the camera is installed and ready to help me out.

You have several different options for controlling an allsky camera. I choose to use a Raspberry Pi and use the Allsky software developed by Thomas Jacquin, a very competent and flexible software. The first thing I did was to test just the camera, Pi and the software to get the basics up and running,

The ASI178MC mounted on a regular tripod for testing.
First test photo from the allsky camera.

Everything worked great and the installation and setup of both the Pi and the Allsky software was pretty straight forward. If you’re planning on setting up a Pi controlled camera with the Allsky software, Chad Sullivan at Patriot Astro has a great guide on YouTube on how to get started – https://youtu.be/7TGpGz5SeVI

Next step was to find a suitable box to contain all the gear and protect them from the elements. I bought a IP67 certified electronic installation box and started planning the layout of everything, where to put the Pi, camera, cables etc. Since these kind of boxes is quite cheap, I ended up using the first one as a test sample for drilling holes etc so I knew what would be best for my final box.

Planning the layout of PI and camera in my trial and error box.

Next step was to order the rest of the gear for the Pi computer. Since the camera will be installed outside and running 24/7/365 you need handle problems like dew, frost and snow building up on your dome. For that my plan was to get weather data from a sensor and feed that data into the Pi. I bought a RPI Relay Board and a DHT22 temperature and humidity sensor for the Pi. With these two components I can measure the dew point and temperature and via the relay board I can let the Pi turn on and off the heater and fans.

Pi, realy board and DHT22 weather sensor.

I hooked everything up using a breadboard to test that I could read data from the DHT22 sensor and be able to control the relays on the RPI Relay Board. The Allsky software has the ability to use plugins, or modules as they are called in Allsky. There is a user created module called Dew Heater that can can be used to read DHT22 sensor data and control relays based on your settings.

DHT22 hooked up to a breadboard for testing.

Then it was time to solder everything together. The dew heater uses 12v and the Raspberry Pi uses 5v so I chose to supply 12v to my box, so I needed to add a 12v to 5v converter inside the box. I’ve seen many other allsky camera builds using POE (Power Ower Ethernet) as a one cable solution to also get the box connected to the Internet. In my case my camera is mounted on my house so I have good WiFi signal and therefore I’m communicating with the Pi wirelessly.

Fitting everything together in the box.

Next step was mounting the dew heater and the camera. I bought the dew heater and the dome from AllSky Optics in UK (https://www.allskyoptics.com). I also ordered the 180 degree lens to replace the original ASI178MC lens that only cover 170 degrees, with 180 degrees you get the entire sky covered in the images.

Camera and dew heater being installed.
Black paint to reduce box reflections in the images.

Last step was to mount the dome to the box and seal it with silicone to protect everything inside. 

Finally the dome is mounted and weather sealed with silicone.

The allsky box is completed and it was time to install it outside. I mounted it to one of my walls using a pipe that extended above the roof top to get above my house and the street lights to get as much dark sky as possible.

Completed camera box installed on top of the pipe.
Final installation done and camera ready to go to work.

The Allsky software I’m using is a really cool software that allows lots of configurations and customizations depending on your need. It controls all the exposures, construction of timelapses, keograms etc.  Here are a couple of screenshots of the Allsky software interface.

This is the live view in the administration web.
There are plenty of different settings you can customize.
All the created media is save locally on the Pi and can be uploaded to a server.

So with everything is place and the camera and software was up and running it was time to start using it and produce some imagery. The Allsky software continuously captures at a interval of your choosing. I’m choosing to take a image every 30 second throughout the night (And day, but I choose not to save those, just use them as a live view). At the end of the night, the Allsky software runs a series of scripts producing different materials of your choice. Besides all the still images you can also get a timelape, keogram (Explained below) and a startrail image for each night.

There are also different modules you can install and one that I’ve installed is a module that can detect meteors in images and save those images separately.

Here’s an example of what the Allsky software can produce. This clip shows some amazing Northern Ligthts that was visible on the 25th of November 2023. 

Another thing that the Allsky software produces is a image called Keogram. That’s a image showing the entire night in one image. In the image below you can see a keogram from the 20th of October 2023. X-axis correspond to time and Y-axis correspond to North to South where North is up and South down.

So from this image we can tell that the Northern Lights started to show up around 21:00 and around 02:00 they almost stretched all the way to zenith (middle of Y-axis). You can also see that the clouds started to roll in around midnight and around 03-04 the entire sky were cloudy.

To summarize all this now that everything been up and running for some time. I’m super happy with the final result! Everything works great and I’m really enjoying following what’s happening in the sky above me, even when I’m asleep. The Allsky software is taking care of all the capturing and creation of material for me to enjoy each morning. It’s so much fun to go through a nights material to see if something interesting was happening.

But the best thing with this camera is that I can keep track of when Northern Lights is actually showing so I can go out and take photos of them. I can also monitor clouds while doing long deepsky photography sessions which really helps evaluating the captured data.

I had some problem with reflections from bright street lights etc. but with some tape I managed to block them out. I can also confirm that the dome handles snow and cold weather really well. The last few weeks we’ve got more than 50-60 cm of snow and the heater is able to melt the snow resonable quick. And my installation allows me to easily take the camera down if I need to fix something or clean the dome from snow or ice if needed. 

So, in the end this was a really fun project and and super happy with the final result. Really looking forward to following what’s happening in the sky and who know, maybe I’ll catch some nice meteors now that the Geminid meteor shower is just around the corner.

Clear skies!

Gear used for the build

– Camera ZWO ASI178MC
– 180-degree FOV 1/2” 1.55mm f2 CS mount
– Raspberry Pi 4 Model B Rev 1.5
– RPi Relay Board
– DHT22 Digital Sensor
– Allsky Camera Dew Heater Module
– DC to DC Converter Regulator 12V to 5V 3A 15W Power Supply
– Allsky Camera Dome 3.5”
– Casing IP66 box
– Allsky software

As for power I’m using a 230v to 12v converter inside with a smart wall socket that I control via Internet if the system for some reason needs to be restarted when I’m not at home.