HOW TO MEASURE SKY QUALITY 

In this video I will explain how to measure how dark the sky is where you observe, what an SQM or Sky Quality Measurement is and how it works and what I was referring to in earlier videos when I said I took SQM measurements of the dark sky sites I visited. I will explain what surface brightness is and how it relates to measuring how dark the sky is and I will also explain other methods for measuring how dark the sky is where you observe, the Bortle Scale, NELM, and using the Little Dipper to gauge sky darkness.