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Two globulars at the edge

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#1 Jef De Wit

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Posted 15 September 2009 - 02:57 PM

Hello sketchers

Here are two sketches I made this summer on a nice dark place in France. I started in astronomy with a 7 cm refractor (Meade ETX-70). My first project was (of course) seeing all the Messiers. I have still one to go (M83)...
It took me one year to realise that it was impossible to see stars in a globular cluster with a 7 cm scope (even M13). I think I looked to much to APOD! The fact that I observe from light polluted areas (my home has a typical NELM of 4,5 mag, a 40 minutes drive take me to a 5,5 mag site) doesn't help much.
Great was my surprice when I looked to M4 in France (much higher in the sky than my hometown). I could see details! At low magnification (x10) M4 looked uniform round. But by higher magnification (x89 and x150) a central bar was visible. It looked like a backbone with different brighter knots.
M13 was also a mighty view. I could detect the globular with the naked eye and averted vision! At x89 and x150 there were individual stars visible at the edge of M13. The globular looked very granulated. At the edge of seeing stars in the globural.
All sketches are made on printing paper with a HB/2 pencil, scanned and inverted. Hope you like them.

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#2 Jef De Wit

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Posted 15 September 2009 - 02:58 PM

and here is M13

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#3 TenthEnemy


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Posted 15 September 2009 - 03:26 PM

You've captured them both very well.

Just a few weeks ago I was shocked when I stopped my XT10 down to 80mm and could still see stars in M13. The whole cluster appeared as fine grains of sand with a few distinct point sources standing out. This was from an NELM of around five.

#4 asteroid7



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Posted 15 September 2009 - 05:19 PM

Nicely done

#5 lunartic65



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Posted 16 September 2009 - 06:39 AM

Lovely images Jeff.

#6 frank5817



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Posted 16 September 2009 - 08:39 AM


Very nice sketches of these fine globular clusters. These are very challenging sketches to make and especially if they look as accurate as these two. :bow: :rainbow: :cool:

Frank :)

#7 CarlosEH


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Posted 16 September 2009 - 11:37 AM


Excellent observations of M4 and M13. You have captured both globular clusters very nicely. They do exhibit the appearance in your renderings at those magnifications. Thank you for sharing them with us all.


#8 Kris.


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Posted 16 September 2009 - 12:53 PM

great sketches Jef, a while ago i had the best view i've ever had of M13 thru my 12" with the bino. it was just like the pictures, better actually cause it looked really 3D. couldn't believe my eyes...

#9 kraterkid


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Posted 16 September 2009 - 04:36 PM

Beautiful sketches Jeff, Wonderful renderings of these two obviously carefully observed globulars. :bow: :D :bow: The central bar in M4 is a very cool capture, makes me wonder what produced that kind of pattern. Great job! :waytogo:

#10 Edwin Quiroga

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Posted 16 September 2009 - 05:26 PM

Did you see that detail in a 70mm scope? Yes, I confirm the awesome views that a little refracto yields from very dark sites. With my 85mm scope I have spotted G1, an extra-galactic Globular at 13.7 magnitude.

Very beautiful sketches!

#11 JayinUT


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Posted 16 September 2009 - 09:52 PM

Jef, terrific captures of M4 and M13. You nailed them I think given your magnification. Thank you for sharing them.

#12 geminijk


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Posted 16 September 2009 - 11:39 PM

I wish I had the patience to draw like that. Working towards it, your certainly encouraging all of us, and thanks for sharing.

I love the way M13 really shows the individual stars.


#13 Jef De Wit

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Posted 17 September 2009 - 09:42 AM

Thanks to all for the kind words. It is indeed fun to push your telescope to the limit of what is possible. Normally I observer with a 12" dobson, but I Like observing with my 7 cm as well (like splitting the Double-Double or observering some tricky Messiers-galaxies).

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