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Pleiades last night


mikeDnight

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Attached is a sketch of the view of M45 through my 4" scope last night. The field stars are positioned only approximately and not all field stars are shown. The nebulosity was more extensive in reality but too subtle to record accurately.

Mike

post-41880-0-64450200-1446996322_thumb.j

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ya dancer......Thats the business. 

I studied some time ago, have the pencils,  erasers , rubbing stones, just no talent in the art of drawing,  especially in the dark. But the item referenced  a standard drawing,  modified to get the results we now see above.

The original  image above shows good artistry,  just weird /  strange in the fact that the original  becomes the negative. 

Good artistry mikeDnight, thanks  BigSumorian.

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Excellent sketch Mike. You obviously find the UHC works despite it being a reflection nebula?

Im glad you liked the sketch Stu. Even though I was observing from an internally blackened observatory the roll off roof still allows too much light to enter my eye. To try and solve the problem I use a black blanket covering my head and focuser which is a great way of stopping light from entering my eye from the side. It really aids with dark adaption. After about 15mins observing with my 20mm XW the nebulosity was very easily seen. I then decided to try the UHC filter and the subtle nebulosity immediately became more evident. That nebulosity is more evident in the image you altered for me and not as obvious in my own negative sketch. Thanks once again.

I think it's time to design a dome to replace the runoff roof.

Mike

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Very interesting, and not necessarily what you would expect. I guess that with good dark adaptation and the black blanket, the UHC dims the sky background more than the nebulosity so improves the contrast? Just shows it always worth trying new things.

How did you avoid a steamed up eyepiece when under the blanket? As I've mentioned before, that's normally what I mistake for nebulosity [emoji12]

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ya dancer......Thats the business. 

I studied some time ago, have the pencils,  erasers , rubbing stones, just no talent in the art of drawing,  especially in the dark. But the item referenced  a standard drawing,  modified to get the results we now see above.

The original  image above shows good artistry,  just weird /  strange in the fact that the original  becomes the negative. 

Good artistry mikeDnight, thanks  BigSumorian.

Hi Charic.

Personally I never make a finished sketch at the eyepiece. I have a sketch book in my observatory that I use for rough observational sketches, which is full of scribbles, corrections, notes and terrible mistakes. After I've made a rough sketch or number of sketches, I reproduce them as accurately as possible soon after the observation, usually on the same night. Also, its important to recognise that the drawings are only representations of what was seen so as to give an idea of what an instrument is capable of showing. Eyepiece drawings always look a bit ropey, so I'd encourage you to keep at it. The cleaned up sketches you produce can be a pleasurable and valuable record of your observations.

Thanks for your kind comments.

Mike

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They say you see more by taking your time and studying.

I for one, never really saw any reason to draw anything to be honest, couldn't see the point at first, with so much technology around,  but then did Sir Isaac have a camera, nope, had to be drawn.

And as shown above, once the image is digitized, manipulated and finished, some of the images I have seen, well they could put my photography to shame!

I`ll be studying some more soon and my Derwents are still sat here on the shelf, ready and waiting.  This is one of the sites I have recently checked out, there are many more.......  http://www.deepskywatch.com/astronomy-sketches.html

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Very interesting, and not necessarily what you would expect. I guess that with good dark adaptation and the black blanket, the UHC dims the sky background more than the nebulosity so improves the contrast? Just shows it always worth trying new things.

How did you avoid a steamed up eyepiece when under the blanket? As I've mentioned before, that's normally what I mistake for nebulosity [emoji12]

I did accidentally breath on my eyepiece twice while trying to control the scope, hold sketchbook, pencil and red torch, as well as trying to hold the blanket in position. After fanning the eye lens with my hand the eyepiece rapidly cleared and all was well. Breathing through my ears might be an option but I'd have to get lessons from my wife for that.

After seeing the improvement the UHC made to the view its hard to believe the nebula isn't to some extent excited by the stars embedded in it and not just a reflection nebula. Either way however, the contrast was improved slightly with the use of the UHC, as the extent of the nebula away from the stars was more easily seen. I found moving the scope now and then brought to my attention nebulosity not immediately obvious.

I think changing the run off roof for a dome may improve dark adaption still further.

Mike

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I did accidentally breath on my eyepiece twice while trying to control the scope, hold sketchbook, pencil and red torch, as well as trying to hold the blanket in position. After fanning the eye lens with my hand the eyepiece rapidly cleared and all was well. Breathing through my ears might be an option but I'd have to get lessons from my wife for that.

After seeing the improvement the UHC made to the view its hard to believe the nebula isn't to some extent excited by the stars embedded in it and not just a reflection nebula. Either way however, the contrast was improved slightly with the use of the UHC, as the extent of the nebula away from the stars was more easily seen. I found moving the scope now and then brought to my attention nebulosity not immediately obvious.

I think changing the run off roof for a dome may improve dark adaption still further.

Mike

Nice one Mike, funny [emoji3]

I'll give the UHC a go, and the blanket of course [emoji12]

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Wow I admire that 4" I rarely see nebulosity in my 16" ,my 5" triplet is some times killed by the uhc but looks like yours is suited to this scope great work

Pat

Hi Pat

The nebulosity around the Pleiades is a strange one. In 1859 the German astronomer Wilhelm Temple reportedly observed this nebula while using a 4" refractor in Italy. Other observers around the world using larger instruments failed to see it, and many doubted the nebula existed at all. Despite this, many observers using larger apertures have been successful in seeing it, and it has been reported to be visible without averted vision in a 16" scope. In fact it is visible in my 4" without averted vision once I'm properly dark adapted, but only as a subtle haze around the brighter stars.

The night I made the sketch shown above, the sky was transparent and I'd been observing the cluster for around half an hour in complete darkness. So in effect, the sketch represents the total accumulation of the incredibly subtle detail seen through the eyepiece over that time, and not the instant view through the scope. I also suspect that the Pleiades cluster carries the designation M45 because Messier actually saw some of that nebulosity around one of the stars, despite his instruments being grossly inferior to anything available to you and I today. Rather than scope type or aperture, i feel a transparent sky and good dark adaption, along with patience is the trick to seeing this nebula.

Mike :-)

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A beautiful sketch; very inspiring.

I've captured the nebulosity in my 6" frac before, but it's tenuous. I've convinced myself I can see it in the 20x80 bins before on a particularly transparent night, but I suspect that was an over-active imagination because I've never read of anyone else doing that.

In the 12" it's very clear.

Paul

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