ASNSW Astro-imaging meeting, Wed 15th June 7:30pm

[tlgerdes]

At the Epping Creative Arts Centre, see website www.asnsw.com (http://www.asnsw.com) for more details.

[tlgerdes]

Preliminary Agenda:

Marc Aragnou has been extraordinarily busy over the last month, with the Prawn (Emission nebula near zeta scorpii) in H-alpha and the Ara shoreline region (NGC 6188) in O-III, and as most of you know has combined these and many others into a giant annotated panorama or map of the southern Milky Way with inserts showing many deep sky objects.
It will be good if Marc can take us through both the new pix and the panorama. One use of the panorama is to get a feel for the interconnectedness of all things, as Dirk Gently would have put it. Another is to use it as a sort of map. A third is to get a feeling for the relative sizes and brightnesses of some of the embedded favourites. We might discuss what other areas are worth mapping similarly.

In similar mapping spirit, Richard Carmichael has had a first go at a very wide field shot (not a mosaic) of the tail of Scorpius in H-alpha using a modded Canon EOS 20D.

During photography of these objects, two interesting questions came up:

(1) How long do you need to photograph in H-alpha or O-III or S-III to get a nice, sharp, grit-free image. This obviously depends on focal length, camera efficiency, the brightness of the object at those wavelengths, binning, and other things. I think that Fred Vanderhaven and I both feel that many many hours are required to get good detailed shots at long focal length, especially for O-III and even more so for S-II, but many of the team have gotten good results in H-alpha using short focal lengths on bright objects. Please bring one or two of your favourite narrowband objects to help get a feeling for the answer to the "how long with what" question, especially with O-III and S-II where you have it.

(2) How do we process narrowband images taken with a colour camera?

Let's discuss general principles, tools and detailed techniques.

Still on the mosaic topic, Geoff Smith has a spectacularly beautiful colour shot of the region from the Gem Cluster through what I call the Chinese Chef and on to the outskirts of the Eta Carinae nebula. This is a seriously lovely shot and I hope Geoff will tell us about how he took it and take us through the result.

Michael Samerski has a most intriguing and salutory set of pix showing the effect of body heat on the steadiness of the image. Again, we can talk about how important it is to keep yourself out of the line of fire, to let the scope equilibrate, the use of fans, the effects of hot roofs and the like.

I've been working (as usual) on the observatory, and mostly just have some funny stories to tell about (a) builders, contracts, insurance, and the like, and (b) the accuracy or otherwise of technical engineering drawings from certain well-meaning dome kit suppliers, and what happens if you believe them, and drill bolt holes where they said to. I also have a slightly more detailed drawing of where things are to go in the dome, which looks at things like how to balance the scope-mount combo over the pier (important when the scope and mount together weigh over 200 kgs), and how far to the north one can hope to photograph with a fork mount. A parallel question for the group: what is the most northerly object you've successfully (a) seen, (b) photographed, either locally or overseas?

One of us (Perhaps Richard - forgive the Alzheimers and remind me) recently took a shot of the Sombrero, in which a number of globular clusters were visible. I dug out a Hubble shot of the Sombero (the "answer in the back of the book" and registered it with my own shot of the same area. Similarly, I registered a photo of part of the Lagoon from Gemini South with one of my efforts. The results were shall-we-say humbling, but it was interesting to see how much could be seen.

[qld]

Trev ,you omitted to mention the annual exuinox dinner held at Wiruna last weekend where the Dining room setting was decked out with candles silver ice buckets and fine cuisine including imported desert,and of course the excellent dinner music provided by Saxaphone Musican and astronomer db ,this is just one of the many events that crop up at wiruna annually and bring a sense of belonging to the astro community, how about a report Trev a second opinion gives veracity to the first

[tlgerdes]

This is just about advertising the AI group, if you want advertise the antics of 40 odd drunken astro bums on a cold Wiruna night, you can write your own thread :lol::lol::P