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Raul Leon
July 14th, 2021, 12:32 PM
Messier 17 aka the swan nebula in Sagittarius; magnitude: 6.0 ; size: 20'x15' ; large and bright, this nebula is beautiful in all apertures. Using a DGM narrow pass band filter, this object shows bright and dark patches. I used a 21mm Ethos at 115x with my 14.5 Starstructure Dob f/4.34389

Ciel Extreme
July 15th, 2021, 04:33 AM
Great sketch!

Howard B
July 15th, 2021, 07:36 PM
Very nice Raul - how long did it take you to sketch it?

Don Pensack
July 15th, 2021, 08:09 PM
A couple recent observations with the 12.5":
Using an O-III filter and 130x, I tracked nebulosity all the way from M17 to M16, verifying visually that these are just bright points on the same nebula.
Using a DGM NPB filter at 140x in a 45' field, I saw nebulosity completely filling the field and spilling out of the field. The "Swan" was only a bright knot in the full-field nebula.
Incredible view, and matching this photo, only in B&W: https://en.wikipedia.org/wiki/Omega_Nebula#/media/File:VST_image_of_the_spectacular_star-forming_region_Messier_17_(Omega_Nebula).jpg
Of course, not with that many faint stars in the field, not the great visibility of filamentary details as the photo.
This is an object whose appearance varies a huge amount with transparency. Some nights it appears like the sketch, others more like the photo.
The variability of appearance keeps me coming back to it year after year.
On that night, the DGM showed more nebula than the Lumicon UHC, Astronomik UHC or TeleVue Bandmate II Nebustar.
This pic shows that M17 and M16 are linked:
https://pages.astronomy.ua.edu/gifimages/M16-M17-CD-rpos.png
I would note that the nebula in between is more visible than the photo indicates.

Raul Leon
July 15th, 2021, 08:36 PM
Hello Mr. Banich, I normally don't spend alot of time on sketches, because I like to just get a quick feeling of what I see....but in this case there was so much faint nebulosity, that I spent a little more time, maybe 40 minutes tops. Raul