Emission Nebula IC5146 Wide Field - AR 21h 48m 28s DEC +47° 25' 57"
Date/Place2020-08-21 at Elijah Observatory
ScopeSkywatcher 80ED
CameraModified 350D
IntegrationIt's an LRGBH composition with the following integration times:

- Luminance: 50 x 600 sec.
- RGB: 25 x 600 sec. for each color channel
- H-alpha: 25 x 1200 sec.

Differently to what I usually do in the processing workflow, I have inserted all the color channels (including H-alpha) at the beginning of the processing. The result immediately seemed to me better than the same version using the system I normally use to mix the H-alpha (in the final non-linear phase), almost at the end of the treatment.
CommentIC5146 is an open cluster with associated an emission nebula, located at about 4000 a.l. from the Earth. It has a diameter of about 15 a.l. Superimposed on the beautiful gem of the nebula it is possible to see a darker "stripe", cataloged as Barnard 168. Close to IC5146 we find the reflection nebula VdB147. The star that enlightens it is known by the initials BD + 46 3471 and is a blue star of main sequence with spectral class B9.5Ve. It has got strong emission lines in the hydrogen band and is classified as a Be star. It is also a variable star of the Orion type. Its distance is equal to 3300 a.l., therefore quite close to the same IC5146. In the same field we can count several dark nebulae from the Lynds catalog, they cover practically the entire field of view. Among the main ones we have LDN1035 and LDN1040.