Unihedron Sky Quality Meter SQM-L with lens

If you are not standing in a completely open place, then lights, trees or buildings on the edge will soon be included in the measurement. The Unihedron sky quality meter SQM-L has a lens for this, allowing it to look at a smaller part of the sky. This way you can more precisely determine the brightness of the night sky, in magnitude per square arcsecond.

This also allows you to measure in a certain direction, for example towards the skylight of a city. This way you can see how strong the light pollution is in your area, which helps with decisions like whether to install a solar panel or not. filter against light pollution or a darker area of observation.

Keep the meter still during the measurement and take a few measurements in succession; then you will automatically see whether the value is stable. When comparing measurements, always aim for the same height and in the same direction.

If you also want to measure with a filter, there is a filter adapter for the SQM-L. If you prefer to measure automatically all night long, then look at the SQM-LU with USB.