José Carlos Dafonte VázquezFreeDSM (Free Dark Sky Meter)
This DIY photometer is part of the project Gaia4sustainability
FreeDSM is a device that allows you to measure the quality of the sky background during your night observations. It is a photometric instrument that incorporates the TSL2591 sensor, with two diodes: one will make a measurement in the infrared range and the other full spectrum. From those measurements, it provides the measurements in mpsas (its range is 12-23 mpsas).
You can build your own FreeDSM with the information contained here, by assembling very cheap and easily available components and some small parts for the chassis that you can print on any 3D printer. It withstands the elements without difficulties, it is small and incorporates a battery, which will allow you to use it portablely, although you can also install it permanently, even ignoring the installation of the battery inside and its charge regulator. The software is based on Tasmota, making it easy to integrate data across a multitude of environments and to include hundreds of additional sensors.
This device is part of the Gaia4Sustainability project and can provide measurement data to our open platform. We say can because FreeDSM allows the sending of data via MQTT messages to your own home automation platform (for example, Home Assistant), it can also save them in the memory of the device itself and, if you allow it, also send the data to our platform, where You can have your own profile and see your FreeDSM data in it.
We hope you enjoy it as much as we have designing and programming it. We also thank the community for their support during its development, and for them it is the result.