TheSkySearchers

On the evening of the 18th to the 19th it was nice and clear.Transparency was all right. In an earlier stage a member of TSS and I talked about the visibility of NGC6781 from the city. Some years ago I had seen it from my backyard with a 140mm Mak, if I remembered well. As I had my 120 mm Evostar on the pier, for examining the big planets ( nice as ever) I tried it with the 120mm. Without UHC there was nothing. With UHC and averted vision it was almost impossible. I just had the slightest hint that there was something out there. Couldn't be sure though.

I decided to bring in the 150 mm. With it was not difficult any more. There it was. At 60 X (exit pupil 2,5 mm) it was at its best: contrast between the object and the sky at its biggest. I was a bit surprised that the 120mm had not done better than it did. Never mind, I had seen it.
The above sketch gives an impression of how I saw the Snowball nebula. In my memory it was sharper defined, but as I already mentioned, that was some time ago.


Later that night Mars popped above the far away buildings. Even though the f/5 achromat is not a planetary scope, I had no trouble observing the "egg" shaped form, the Southern Icecap and several darker and brighter surface details. It comes down to not getting distracted or irritated by the colors around it.

That's a nice sketch, John. Thanks for sharing!

Nice sketch John, thanks!

Nice sketch John!

Cool sketch John and it sounds like a very nice view through the 150mm scope. Hope you will be able to get out again soon.

Sweet!

Mission accomplished. Someone in my environment suggested to observe NGC 6781 with an OIII filter instead of the UHC I used the other night. So I did. And indeed, with it it seemed a tiny bit brighter, but that was not the most important. With averted vision the rather sharply defined edges appeared, and that was I was looking for. It wasn't a sloppy blob of light any more, but a strong impression of a nice annular form of light. Found it!

Really good website about comparisons of performance of some filters on several objects: https://www.prairieastronomyclub.org/fi ... n-nebulae/

Very nice John and congrats on picking up NGC 6781. Fine sketch as well. To add perspective to your observation from a brighter city environment with smaller aperture and filter, here is my own observation (sans sketch) using 17.5 inches from a dark site a couple of years ago:

NGC 6781 (Aquila, planetary, mag=11.6, size=111.0”x 109.0”):

Easily swept up at 110x without a filter, it presented a large (for a PN) bright out of round orb of gray light. Its southern rim was brighter than the rest of the shell giving the illusion of a crescent of brightness. It seemed surreal floating in the dark sea of the sky and I found it simply a beautiful object.

Wonderful presentation and sketch John!

Thank for sharing it with us all

Very nice work John!