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Old 29-04-2014, 11:41 AM
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mental4astro (Alexander)
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Join Date: Jun 2008
Location: sydney, australia
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From IISAC '14, wide field sketches

Thank you Stew, Jen and Sab.

This last weekend saw IISAC '14 happen. I arrived late on the Friday, and when I finally settled at the camp it was dark and I just didn't feel like setting up a big scope. The sky was clear, the full brilliance of the Milky Way was arcing overhead, so it was a great chance for some wide field sketching with my little 4" achro.

Omega Centauri and Surrounds

My favourite eyepiece for this little scope is my 30mm 82deg Explore Scientific bruiser. As this scope and EP combination gives me a massive 5deg TFOV, I'm always thinking "hmmm, I wonder how much of that patch I can see...". "That patch" this time was Omega Centauri and Centaurus A. Cripes! I could actually get BOTH in the one field of view!!!

Greed took hold and I wanted to sketch that entire FOV. Exhaustion from the long drive to camp took hold and I could only manage the area around Omega Centauri. But I am still so pleased with the 'cropped' sketch. Omega is seen resolved into a little ball of thousands tiny, tiny pin-point diamonds. Surrounding Omega is the mottle background of the Milky Way, and a lovely large darker patch to the left of the cluster, and another dark but smaller patch to its upper right. This big picture scene is totally missed when we magnify Omega. Blooming brilliant patch of sky,

This sketch represents approx. 4deg TFOV.

Object: Omega Centauri and surrounds
Scope: 4" f/5 achromatic refractor
Gear: 30mm 82deg Explore Scientific, 17X
Location: Lostock, NSW, Oz.
Date: 25th April, 2014
Duration: approx. 2hrs

Jewel Box and the Coal Sack

A little rest and back to it. Some time ago I had made a mental note of a potential sketching target as being the area around the lovely cluster The Jewel Box in the Southern Cross. The great thing about the same scope and EP combination is the TFOV encompasses the Jewel Box, Mimosa or Beta Cruxius, and the eastern edge of the dark nebula The Coal Sack, all set off against the mottled background Milky Way. Gorgeous stuff!

The Coal Sack is also surprisingly detailed. Streamers of darker lines, patches of brighter, and ghostly arcs. These details made for a great challenge as they are, well, black... Another fainter open cluster can also be seen just to the upper right of the Jewel Box. The Southern Cross contains dozens of open clusters within its boarders.

This sketch is very close to showing the full 5deg True Field of View I had.

Object: Jewel Box and the Coal Sack.
Scope: 4" f/5 achromatic refractor
Gear: 30mm 82deg Explore Scientific, 17X, 5deg TFOV.
Location: Lostock, NSW, Oz
Date: 25th April, 2014
Duration: approx. 2hrs
Attached Thumbnails
Click for full-size image (Omega Centauri wide field.jpg)
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Click for full-size image (Jewel Box and Coal Sack.jpg)
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