IC 5146 – The Cocoon Nebula in the Constellation Cygnus
IC 5146, better known as the Cocoon Nebula (also catalogued as Sh2-125 and Caldwell 19), is an emission and reflection nebula with an embedded open star cluster in the constellation Cygnus (the Swan). The cluster carries the designation Collinder 470.
This image was taken over several nights between the end of May and September 2026. It is the first time my new camera, a ToupTek ATR2600M with Antlia LRGB and 7 nm narrowband filters (here only Hα), was put to work. The corrector on the Lacerta FN250 telescope with its 1000 mm focal length is a TeleVue Paracorr Type II, which extends the focal length by a factor of 1.15 to an effective 1158 mm (f/4.6). Adapting the corrector, together with a rotator inserted between focuser and camera unit, called for individually machined adapters. After a few learning steps, this is now the first light of the new setup.
The Cocoon Nebula in the Constellation Cygnus, Telescope 10" Newton f=1000mm, Camera ToupTek ATR2600M, Total Exposure Time 31h42min