Ok, I had to bite the bullet tonight and undertake a big 'un, Omega Centauri.
Again I used my easy to use (1 min. set up time) 8" f/4 scope. With such a short focal length, I had to use a short focal length EP to get any resolution. The TMB Planetary Type II 9mm I recently bought from Sylvain here on IIS was just perfect.
This GC is amazing. Averted vision with this little scope from home reveals SO MANY STARS. But it also allows for faint concentrations of strands of stars to trace out fine patterns, and variations in density. Near the centre there appears to be a void of stars, but it is most likely a chance line-of-sight fluke, but there are very faint stars that occupy this space.
I did have a lot of fun with this one. Most of the time I was pot-marking the page with tiny dots. It extends so far, and with it's location in the sky, its outer edge blends into the surrounding 'noise' of the Milky Way.
Do I dare revisit this Titan with my 17.5"? , probably.
Object: NGC 5139, Omega Centauri
Scope: 8" f/4 dob.
Gear: 9mm TMB Planetary Type II, 89X
Date: 29 March 2011
Location: Sydney
Conditions: Sydney light polluted skies
Media: white pastel & white charcoal on black paper
Thanks for the comments, lads. Omega Centauri has always scared the heebee-geebees in me to even contemplate as a sketching option. Scott's work on GC's gave me the nerve to have a go.
The stars in the sketch are done in two ways: after making the initial 'ball' with the pastel and brush, the brighest stars were marked. The fainter ones where than 'machine gunned' on to achieve the desired effect of details like the arcs and various compact concentrations.
I don't think an illustrator today would sit and mark down each individual star. These sketches in the end are only a representation, not a photo, so there is a degree of license.
This rough and ready sketch was done in less than 1hr. A small scope and a light polluted sky does much to tone down Omega. That helped.
I think your are leading the way for us Alex. In this day of digital photography there is not a whole lot of point in trying to be scientifically precise with sketches. It is more about an artistic impression and recording as much as you can see naked eye.
Clear skies last night - one of the fruits was some good views of NGC 3242, the "Ghost of Jupiter". Alas not quite as good as during a brief session a couple of nights before when I could observe it at 450X. But still not bad - here is a sketch made with pastel pencil on black paper, photographed with some adjustment to contrast in GIMP.
I like the amount of detail you've put down. The variations in shell brightness, scale, and the slight brightening along the very edge. These are the details that challenge the observer to identify. Not a big target, but the degree of complexity would trip up many who would try to describe this PN in detail. Your sketch has is in 'black and white'.
Clear skies last night - one of the fruits was some good views of NGC 3242, the "Ghost of Jupiter". Alas not quite as good as during a brief session a couple of nights before when I could observe it at 450X. But still not bad - here is a sketch made with pastel pencil on black paper, photographed with some adjustment to contrast in GIMP.
Awesome sketch paddy,
A very accurate representation of what one may expect from this magnificent planetary,nice work.
It has been quite a while since I last observed and I could not miss this clear night opportunity on the 1st of April.
Here is a sketch of my favourite OC,Tau canis majoris cluster or ngc 2362 from the night,
Instrument-12'' dobsonian Eyepieces-26mm plossoll and 15mm plossoll magnifications- 57x and 100x conditions-cold, dewey(My secondary dewed up only 2 hours into thesession and i decided to call it quits,is this normal for a solid tube.) seeing-3/5 Sketch details-Sketch materials used were white printer paper and a 3b pencil and a 3h pencil.I first plotted the main star tau and several other bright field stars to anchor my sketch I then worked my way around the cluster using the stars to gauge distance and try to accurately postion the stars,After I am happy with the plotting of the stars I give more weight to the brighter stars to make them stand out.That is all done at the telescope after going inside I fix up the neatness and then process it on the computer using gimp also adding colour to stars I thought had colour. Object details-Sketch says it all,a Magnificent open cluster a must see for those who have yet to observe it.
Thanks for viewing
Cheers Orestis
ps-regarding cardinal points west is to the right and north to the top.
Lovely sketch of a very beautiful OC, Orestis. Well done.
BTW I found that Scott Tannehill's fan modification for the GSO dob got rid of any secondary dew problems on mine. http://www.iceinspace.com.au/63-400-0-0-1-0.html I found that I didn't need to change the mounting of the fan as the vibration was minimal - I only put the cover around the back of the scope with a gap for the fan inlet to push the air into the tube and stop it bouncing back off the primary and put the baffle a few cm above the primary to direct air over the primary. Neither mirror ever dewed again. I could feel the gentle flow of air out of the end of the OTA. It also meant the primary cooled down much quicker and the scrubbing of the boundary layer meant I could go to higher powers sooner.
Your sketch of the OC is a very good one, particularly as it includes the electric blue of Tau Canis Majoris. Colour is one aspect that is often missing from astro sketches. Sometimes, not because the object doesn't seem to have colour, but we either miss the colourful stars, or we hesitate in using grey or even a pale blue in the item, an white alone doesn't quite do it on its own.
Particularly with galaxies, GC's and nebulae. Grey can soften the otherwise harsh white, and the blue gives an element that white just doesn't have. Our eyes perception of low light isn't strictly 'black and white with shades of grey'. It's a little more complex.
Made this sketch a couple of nights ago. Seeing and transparency were nothing to crow home about, seeing especially was poor. Used an OIII filter which did an excellent job of enhancing contrast.
also...
B33 - Horsehead Nebula. From my last obs seasion back in December! Used the H-beta filter.
These two sketches are positively outstanding, mate!
The Horsie shows that it is observable in sub 1metre apertures,
And the spiral planetary shows such subtlety of touch, and acute observation from a target that lies in one of my favourite constellations, Musca. It doesn't have a great deal of DSO's, but those it does richly reward and challenge observers who care to look.
17.5" scope, three hours and Eta Carina, again from Sydney
Finally, a clear night!
It started looking dodgey, but the clouds parted to reveal stars! Even from Sydney! Woohoo!
Heartened by my attempt at Eta Carina Nebula with an 8" dob, tonight, armed with a battery of sketching implements, I trained my 17.5" dobbie at the same target.
This time, I also used my Grand Daddy of eyepieces, a 35mm Masuyama. A bit long for my f/4.5 scope, but them's the breaks, .
This is such a busy place. There are nebulae within nebulae, multiple shockwaves, burst of star formation both just initiated and freshly kicking off their nuclear fires, and a super massive star about to go supernova.
Man-O-Man, what a nightmare of detail. Three hours of work, and the result is below. My nervous tick twitches at the thought of doing all this again from a dark site, . Ooooh, it's gonna be soooo much fun, !
Scope: 17.5" f/4.5 dob
Gear: 35mm Masuyama, 57X, & OIII filter
Date: April 8, 2011
Location: Randwick Girls' High School, Sydney
Media: White pastel, white & black charcoal pencils, white chinagraph, white and coloured ink on black paper.