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Norman
August 21st, 2016, 10:24 PM
Hi folks,

this is one of my favorite groups - that´s why i finally made a sketch of it...

I made it a few days ago with my 12“-Dob, NELM 6m5+, seeing 2.

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My approach was just going out and trying to catch whatever comes into view after a while. I did not use any help as DSS or somethin. I guess there are a few galaxies more within reach of 12“ when having any print at ones knees or better conditions and so on.
One of the tiny two stars with the little smudge between is actually no star but a little round galaxy itself too. And another smudge actually is a star :D ... But i didn´t change this in my sketch because it was my impression at that time. Named tiny star(s) have been easily visible with averted vision but were not to hold permanently.

The object is just entering best observing time – i am interested in your results! :-) Hope you enjoy my sketch so long until moon is vanishing...

CS!
Norman

Uwe Glahn
August 24th, 2016, 08:33 PM
Hey Norman,

not an easy job to see the faint smudges in the NGC 70-group with 12". Must be a good mirror :) I have some difficulties with your sketch, especially the orientation (very important for a sketch) and the approx. field size.

Norman
August 25th, 2016, 08:18 AM
Hi Uwe,

good mirror... maybe ... or good site ;-) Thx 4 your reply :-)

Orientation: my goal is to sketch good enough that north arrow is not necessary - obviously i failed ;-)

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Just turn pic 120 degrees counterclockwise. Field might be around 0,6 degrees in original sketch.

CU and CS
Norman

Uwe Glahn
August 28th, 2016, 11:14 AM
Thanks Norman, now I got it.

As I said before excellent result with 12". I remember the NGC 70 group as a more difficult group in my former 16". Nothing bright there.

I re observed the group yesterday and despite 5x larger aperture my very first impression was very the same as your sketch showed. Good work!

Norman
August 28th, 2016, 07:10 PM
Hi Uwe,

thank you again :-)

12" is perfect size for Arp 113 - with an area of 113²inch... ;-) Calculating this way bonus object for 16" is Arp 201 - also object of this season :-)

To get serious again - Nice that you observed this group again! I am very curious about your result then!

CS
Norman

mdstuart
September 3rd, 2016, 07:05 PM
Well done Norman. I observed this area a while back with my 16 inch in mag 5 skies. I could only pick out NGC 68 and NGC 71 with averted vision. I tried for the others but could not get them. I suspect dark skies and an accurate mirror 1/10 wave or better? helped you.

Mark

Norman
September 4th, 2016, 11:57 AM
Hi Mark,

thank you. Transparent skies are basic requirement to see all these galaxies of course. Just like said, sky was of good qualitiy (NELM 6m5+), rather 6m8. So having 5mag-skies it is not suprising that you saw much less with even bigger scope.

Mirror quality doesn´t play a significant role at this low power (170) i´d say. But yes - mirror is of very good quality with figures you mentioned (1/13pv) :-)

CS!
Norman