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Uwe Glahn
January 16th, 2021, 09:15 AM
Despite the lockdown restrictions, heavy snowfall in the mountains and freezing cold I tried to observe and sketch the "Pleiades Bubble", Mel Bartels (https://www.bbastrodesigns.com/drawings.html#Pleiades) and Howard Banich (https://sites.google.com/site/howardbanichhomepage/observations/observing-notebook-scans/notebook-11) already documented. The faint background nebula are almost related to photographically discovered nebula from E. Barnard [1894] and M. Wolf [1900], which were registered in the IC II (here: IC 336, 353, 354).

I used a homemade 4-inch binocular-telescope with a field of 4.9°. The sketched field is around 4°x6°. The magnification was 14x and the naked eye limiting magnitude near 7mag.

The sketched nebula were not as hard as I thought they were. Despite the nearly 5° field of the binocular-telescope, I had to move the telescope to notice the brightening. But all brighter sections were clearly to reproduce and separable from regions with higher star density. The brightest (in contrast to photographs of the region) section and a good starting point to see the nebulas was an east-west elongated glow around 1.5° SW of the center of M 45 (= IC 336/LBN 773).

4172
home (http://www.deepsky-visuell.de/Zeichnungen/M45_IFN.htm)

wvreeven
January 16th, 2021, 10:24 AM
That's an incredible sketch Uwe. It looks like a photo to me.

Wouter

Uwe Glahn
January 16th, 2021, 12:41 PM
Thanks Wouter for your response. Although the stars of the Pleiades were only embellishment, I made sure that the impression of the stars were as real as I could illustrate. Everyone knows the look of the Pleiades, so the stars have to match also.

Howard B
January 16th, 2021, 09:38 PM
Excellent sketch Uwe, and your observation shows how important a wide-field instrument is to see the Pleiades Bubble nebulosity - you need a lot of space around the brightest stars to see the subtle nebula well.

akarsh
January 16th, 2021, 10:30 PM
Exceptional sketch, Uwe!

Paul Alsing
January 17th, 2021, 02:16 AM
That's an incredible sketch Uwe. It looks like a photo to me.

Wouter

I agree, it looks just like a photo!

Uwe Glahn
January 17th, 2021, 08:26 AM
Thanks Howard, Akarsh and Paul.
Howard, I wish I had just more room around the stars. Maybe 7° could be a sweet spot, where IC 341 comes also into the field.
Paul, I tried to become a realistic copy of the visual impression so I made a time-consuming sketch of the limiting magnitudes especially inside and in the direct neighbourhood of M 45. But to my experience it is nearly impossible to sketch the logarithmical brightness sense of our eyes, so yes, it looks more like a photo.

cloudbuster
January 17th, 2021, 04:08 PM
Great observation and wonderful to see a sketch of the area around M45 this large. Unlike the Merope nebula, I had a hard time to see the Maia nebula (LBN 772) myself. In your sketch it appears only slightly more difficult. I'll pay attention to the surrounding nebulosity next time. Thanks for sharing your hard work.

Norman
January 25th, 2021, 03:30 PM
Hi Uwe,
at first a wonderful New Year for you.

I have no idea of how hard the background nebula is - but alone your sketch of the Plejades itself... is the most natural one i have ever seen of this object.
You may know my respect to you and your level as visual observer. But with this pic you really dropped the bomb... It´s nice and interesting to see that even for you there is still something to improve in comparison to former sketches. Your stars in this pic are just beautiful.
For me - this is technically your very best sketch. Congrats to that unbelievable drawing Uwe.
How long did it take to sketch all these stars?

CS
Norman

kisspeter
January 26th, 2021, 08:53 AM
Beautifuf drawing, Uwe! I've only seen the brightest parts of the nebula so far with my little 4". Around the main stars of M 45. I have a very old and pretty ugly drawing. Next time I'll try to take a deeper look.

I very much agree with what you said about drawing the stars. I also find it basically impossible to capture what I see in the telescope. I think we as visual observers are very much privileged to see the beauty of the sky live. The razor sharp and tiny stars ranging from extremely bright to very faint. A simple graphite dot cannot really do justice to the beauty of the stars.

Uwe Glahn
January 28th, 2021, 03:53 PM
Martijn, Norman and Peter,

thanks for your nice words.

Martijn, although the Maya Nebula is the second brightest glow of all Pleiades Nebula, it was not easy to see because of the small size (with 14x) but it leak out in northern direction within a rich star field, which looks nebulous at all. In the sketch, the Maya Nebula is turns out a little bit to bright. In your 16-inch the nebulas should be much less a problem, when the transparency is good enough - see my past try with 16-inch. (http://www.deepsky-visuell.de/Zeichnungen/M45_16.htm)

Norman, the main goal were the background nebula and not the stars at all. But to redraw the stars in the fine sketch was the harder work. I don't look at a watch but I guess I needed around 1-1.5h to sketch all the stars in the fine sketch (format A4). But of course there are always things to improve, also for me after nearly 30 years of sketching experience. To see other observers with technical better sketches is a motivation to get better.

Peter, you are right, it could only be an approach to represent the visual impression. Maybe it is possible to work with intensities (different greyscales) with all stars instead of the size of the stars. But this means a very work-intensive digital rework of every single star. Maybe I will test it in a sketch with muss less stars.