I’ve noticed previously that it never gets truly dark at the Boulder Flatirons. Even on a moonless night, light from the city illuminates the rock and any clouds above. Tonight there were light patchy clouds drifting south, which tempted me to try another stacked exposure but this time with the added element of the clouds. I think this might have been better if the cloud had been low enough to roll over Green Mountain (in which case I’d have gone for a tighter shot), but happy with the result.

Technical details: 20 x 30s exposures, 18mm, f/3.5 at ISO 400, stacked with StarStax.