PixInsight: best 28 of 60 3 minute exposures graded, selected, stacked, and exposure stretched with linear noise reduction and sharpening
Topaz DeNoise: AI based noise reduction
Photoshop: final crop and exposure

Ides of March Rosette Nebula. There is a wealth of deep sky beauty hidden behind gray urban skies that appear to show only the brightest stars. Longer exposures, sky glow filters, and image processing can lift the veil on deep sky wonders. The Rosette Nebula (NGC 2237) is a stellar nursery high in the March sky. It and its newborn blue spangled open cluster, NGC 2244, are about 5500 light years from earth. This image shows what can be captured with a small 2" telescope and a few hours exposure time using modern image processing to remove the urban sky glow in a Bortle 6-7 urban sky.