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View Full Version : M 45 Pleiades, where are you ?



Bertrand Laville
September 18th, 2018, 06:46 PM
Hi All,

Am I wrong ?
I do not see in DSF any drawing of M 45, neither in "sketches & Images" nor in OOTW...
Moreover neither with small nor big scope...
Only Merope and Barnard's nebulae, which are only parts of it.
Could you help me?
Thanks

Bertrand
http://www.deepsky-drawings.com/

Howard B
September 21st, 2018, 07:22 AM
Hi Bertrand,

I haven't looked for drawings of M45 here, but here's my drawing:

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These drawings were part of my January 2017 article about the Pleiades in Sky & Telescope magazine, and depict the view through my wife's 8-inch f/3.3 Newtonian. You'll also notice faint nebulosity all around the main stars of the cluster, which Mel Bartels re-discovered a couple years earlier at first light with his 6-inch f/2.8 Newtonian and dubbed the Pleiades Bubble. His scope and sketch are here: https://www.bbastrodesigns.com/6inchF2.8/6%20Inch%20F2.8%20Telescope.html

I imagine you have a wonderful drawing to share and look forward to seeing it.

kisspeter
September 21st, 2018, 09:06 AM
I only have a very old and bad drawing of M 45 with my 4" from 2000-2001 (2 nights). I would like to make a better one but I've not yet figured out how exactly I would like to do it. I think I'll need to find a very small scope with a big field (I don't like drawing with binoculars) + a bigger scope for the details. But not a really big one because I don't want to spend a whole winter with M 45. So I think this project will have to wait.
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Bertrand Laville
September 21st, 2018, 02:38 PM
Hi All,

Thanks Howard and Peter for your answer.
Actually, my question to know if there were some post about the Pleiades was not for a question of drawing, but a question of color, depending on how big the scope is.

Here is the matter*:
When I observe M 45 with a rather small scope, and a DS Lumicon filter, all the nebulosities are seen with a weak blue light, the color of which is the wellknown blue of reflection nebulae. http://www.deepsky-drawings.com/m-045-l80/dsdlang/fr

But when I observe the field with a large scope, the colors are different*: without filter, stars and nebulosities, all of them, are white, or rather show no color.
But with the DS filter, all nebulosities are light blue, the same blue as previously described (scaled C 130 / 135 in color scale of Photoshop or Paintshop Pro, or any other file), EXCEPT Merope nebula.
Merope nebula is obviouly not blue, but a kind of dirty white, more or less brownish (that I scaled C 15 / 20)
http://www.deepsky-drawings.com/m-045-t635/dsdlang/fr

I've never heard about this difference of color in Pleiades' nebulosities, and it is why I asked my question, and waited for your observation reports.
What do you think about that*? Is it possible that there is a part of H alpha in the light of Merope nebula*?

Clear skies
Bertrand
http://www.deepsky-drawings.com


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Howard B
September 22nd, 2018, 07:57 AM
On the best nights I've seen a warm hue to the curved part of the Merope Nebula, but I've not seen a blue-ish hue in the other parts of the Pleiades nebulosity. The brightest stars have are wonderful brilliant white with a slight blue hue though. The warm hue of the Merope Nebula may be from H alpha - I don't know - but I've thought that it was that it showed the color difference between nebulae that was far enough away from the brightest stars to reflect light from all the cluster stars. This APOD photo shows it pretty well: https://apod.nasa.gov/apod/ap150617.html

Howard B
September 22nd, 2018, 07:58 AM
Beautiful rendering of M45 Bertrand, that's the loveliest drawing of them I've ever seen.

Bertrand Laville
September 25th, 2018, 01:27 PM
In addition with this discussion, here is an old drawing of IC 349, Barnard's nebula
with very detailed report here: http://www.deepsky-drawings.com/ic-349/dsdlang/fr

Bertrand
http://www.deepsky-drawings.com/


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Tom Axelsen
October 26th, 2018, 12:50 PM
Hi All,

Thanks Howard and Peter for your answer.
Actually, my question to know if there were some post about the Pleiades was not for a question of drawing, but a question of color, depending on how big the scope is.

Here is the matter*:
When I observe M 45 with a rather small scope, and a DS Lumicon filter, all the nebulosities are seen with a weak blue light, the color of which is the wellknown blue of reflection nebulae. http://www.deepsky-drawings.com/m-045-l80/dsdlang/fr

But when I observe the field with a large scope, the colors are different*: without filter, stars and nebulosities, all of them, are white, or rather show no color.
But with the DS filter, all nebulosities are light blue, the same blue as previously described (scaled C 130 / 135 in color scale of Photoshop or Paintshop Pro, or any other file), EXCEPT Merope nebula.
Merope nebula is obviouly not blue, but a kind of dirty white, more or less brownish (that I scaled C 15 / 20)
http://www.deepsky-drawings.com/m-045-t635/dsdlang/fr

I've never heard about this difference of color in Pleiades' nebulosities, and it is why I asked my question, and waited for your observation reports.
What do you think about that*? Is it possible that there is a part of H alpha in the light of Merope nebula*?

Clear skies
Bertrand
http://www.deepsky-drawings.com




Hi Bertrand,
On the night 15. to 16. October I was out observing with my 20". One of the last objects I observed was M45, no filters and with a TV 35 mm Panoptic (EP=7mm). At that time I had not read this thread.

Apart from the impressive brilliance of the stars, it was the impression of colors in the nebulas that made an lasting impression in my memory. Merope Nebula was a bluish white close to Merope, farther away the nebula was a dirty brownish hue, weak, but clear enough, that I took notice of it.

Clear skies
Tom