Owl Nebula, NGC 3587

Most data in this image were obtained with the reflecting Zeiss telescope of 1.23 m at Calar Alto Observatory, in official time of the Andalusian Network for Technical and Scientific Public Outreach (RECTA), through an agreement with the Documentary School of Astrophotography (DSA). Some data come from the 2.2 m and 3.5 m telescopes placed at the same observatory. Images with different integration times were obtained with filters Strömgren b, H-beta, O-III, Strömgren y, and H-alpha, completing 300 minutes as a whole. The information from those filters was distributed among the three colour channels (blue B, green G, red R), as indicated in the attached figure. Strömgren data were used to compute the fluxes of continuum emission at wavelengths of 450, 550 and 650 nm. Also, each emission line was assigned a concrete colour hue. 

processed by Vicent Peris, José Luis Lamadrid, Jack Harvey and Steve Mazlin with the program PixInsight.