IC5146 - The Cocoon Nebula

[MarkS]

The Cocoon Nebula taken on two nights (2 & 3 August 2010) from Riberac, France.  Taken early in the night before the moon became too troublesome.

H-alpha modified Canon EOS 350D on Banana Scope (Tak Epsilon 180ED at F2.8 )

33 x 5 min at ISO 800 + 3 x 5 min at ISO 100



Larger version here (2/3 scaled):
http://gallery.orpington-astronomy.org.uk/albums/userpics/10046/cocoon03082010.jpg

Mark

[mickw]

Nice one

Are the stars a little bloated on the large version or are my eyes buggered ?

[Fay]

cannot believe how many stars are in that area. Very nice Mark. Great dark lanes

[RobertM]

Wow!!! that's nearly perfik !!!

Excellent job Mark, though I suspect good data helps a bit

Robert

[Rocket Pooch]

Hi Mark,

Very nice do you know why the stars are a little fuzzy?  Also I did see a picture somewhere with the head of the nebula in the bottom left and the dark tail goes on for ages.

Chris

[MarkS]

Thanks for the comments.

Mick, Chris - I don't know the exact reason for the "fuzzy" or "bloated" stars but it's probably something to do with my processing - I found it difficult to bring out the dark lane without bloating the stars.

Chris - you're right - Barnard168 (the dark lane) does extend even further.  In hindsight I should have framed it with the Cocoon further down and left in the image.

Mark

[Rocket Pooch]

Hi,

It is a great image Mark, I'm wondering what to do next so people go wow, your kinda hogging it all.

Chris

[Tony G]

You could always run naked through the fields, chasing black sheep, I bet that would make a few people go 'WOW!!!!'
Thinking about it, I think thats been done at Tuesnoad.

Tony G

[MarkS]

It is a great image Mark, I'm wondering what to do next so people go wow, your kinda hogging it all.

Sorry mate - I didn't mean to hog the whole Universe! 

The Achilles heel of my setup is that I'm essentially restricted to RGB.  If you pick a subject that looks spectacular in narrowband with false colour (e.g. using the Hubble palate) then I won't be able to touch you!

Mark

[Rocket Pooch]

Good, that means I just need to break Robert's kit then.

[Rocket Pooch]

I thought I'd done this, this was with an HX916 Mark, with an ED80, your FOV is amazing.


Cocoon-20070912 by chrissuddell, on Flickr

[MarkS]

Chris,

The FOV is due to the big CCD.

If you try the Cocoon again with your latest astro-camera on your ED80 with focal reducer, you'll get a field of view almost as large.

Mark

[mickw]

that I'm essentially restricted to RGB

Just curious..........

If you were to set the DSLR to B/W mode then use a narrow band filter could you then process that data as true narrow band to supplement the RGB or is the CCD not sensitive enough ?

[MarkS]

If you were to set the DSLR to B/W mode then use a narrow band filter could you then process that data as true narrow band to supplement the RGB or is the CCD not sensitive enough ?

A DSLR does not have a true B/W mode  -  the CCD pixels each have a permanent  R, G or B filter on them.  So if, for instance, I use an H-alpha filter then only the "red" pixels will react since the H-alpha wavelength is red.  So only one quarter of the pixels will be of any use.  It is still worthwhile to do this (indeed I have taken some H-alpha images) but it is far better to use a dedicated B/W astro-CCD where all the pixels will receive a useful signal.

Mark

[Tony G]

Excellent image Mark,

I take where you are in France helps in the clarity of the image?
I wonder what my 350d will produce when we go in September.
I can only dream of images like the ones above, and many more within the society, but maybe one day I can get somewhere faintly near these.
In the meantime I'll make use of what I have.

Tony G