Omega Centauri versus 47 Toucan

[Bertrand Laville]

Hi All,

To follow the hereabove message concerning Omega, I propose a comparison beetween the two most extraordinary globular clusters that are Omega Centauri and 47 Toucan.
To my mind, the comparison is as interesting as the two globulars are totally different: Omega is a monster, when 47 Toucan is a jewel.
Here is a sketch (and not an image ) with the two globulars at the same scale, seen from the same scope, 20" Obsession, and the same place, Tivoli lodge, Namibia.


47-Tuc-vs-Omega-Cent-T508-BL-Tivoli-2012-2004.jpg

Here are the reports:
for Omega: http://www.deepsky-drawings.com/ngc-5139/dsdlang/en
for 47Tuc: http://www.deepsky-drawings.com/ngc-104/dsdlang/en
for comparing both: http://www.deepsky-drawings.com/ngc-...139/dsdlang/en

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

[kisspeter]

This is a great idea. Before our first trip to the south I had seen a "comparison" with different telescopes and magnifications (M 13 vs. Omega Cen and 47 Tuc). It was absolutely not informative. So I decided to do a proper comparison myself. I chose 40x enlargement (10 mm Delos, 1.8° field of view) with my little 4" Newtonian. I drew M 13 before our trip. And I was very curious to see the big ones.

4", 40x, 1.8° field drawn into a 10 cm circle, 2012, Hakos, Namibia. "Ny" stands for West.
ngc104_kisspeter.jpgngc5139_kisspeter.jpg

inverted:
ngc104_positive_kisspeter.jpgngc5139_positive_kisspeter.jpg

Both drawings started with an empty circle and contain information gathered only at the eyepiece. All stars were drawn by position except for the globulars' members that were impossible to draw by position. On the final drawing I tried to draw the resolved globulars in a way that you can see which stars were drawn by position (small minority) and which were drawn randomly to reflect the overall feel of resolution (I took a lot of notes by the eyepiece).

Omega Centaury is probably my least precise drawing. I had to erase and redraw about 1/3 of the field stars because I misinterpreted something. It was already towards the end of our 2-week trip after about 10 nights of drawing.
Also, as the final drawing of Omega Cen was ready I started to doubt that it is realistic. I processed the sketch more than a year after observing and I was not sure how bright it was. But I took a look at it again in 2016 (same telesope + eyepiece + localtion) and I was relieved that my drawing is realistic.

My drawings of globulars

[Dragan]

Wow! I really don't know what to say.

All of these sketches look like photographs. They really do. I'm so impressed!

[kisspeter]

Thank you Dragan.

Bertrand, I didn't write previously but your drawings are amazing. And I totally agree with the monster / jewel simile.

[IVAN]

Fantastic rendition of these two globular clusters Bertrand, very realistic representation.