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Here is my first DSO travel report from the south Pacific:
A week ago I arrived at Lizard Island (14°27 S, 145° 27´E) for research on their marine biological station until early January. It must be one of the darkest places on earth. Lizard Island is situated on the Great Barrier Reef about 20 km off the Australian coast and this far north in Queensland there are very few human inhabitants on the mainland and no light can be seen there from here. Closest town is Cairns 200 km to the south.
I have been here virtually every December since 2002 but for the first time I now brought a travel kit for astrophotography. It consists of a SW StarAdventurer and a 300mm f/4 Canon telephoto lens with an ASI071 OSC camera. Having a cooled camera here is essential. I have once tried some AP here with a DSLR with extremely noisy results since the night time temperature here is rarely below 25°C. I also brought my PoleMaster camera for polar alignment. The whole kit with tripod weight 8 kg. The lens is only 1.2 kg.
Focusing a telephoto lens precisely is tricky so I had to invent a microfocuser made from a folded sheet of aluminium cut out from a beer can. I shaped the sheet into a rod that presses onto the edge of the focusing ring by the force of a rubber band. Functioning a a lever it provides both a fine micro movement and fixes the ring so focus does not slip.
Even if Lizard Island is close to paradise there are unfortunately also clouds, but so far I have had two relatively clear nights. First night was spent trying to find the very faint constellation of the Octans and its southern pole star. This was not easy for someone used to the northern hemisphere with the bright Polaris, and I had to print out a bunch of star charts just to get some orientation. When I finally found it clouds moved in of course.
On Friday night it cleared from midnight until sunrise, and PoleStar helped me do what appears to have been a perfect polar alignment. I then aimed at the Large Magellanic Cloud and collected 145 x 90s of data, so about 3.6 hours, which is rather ok with this fast lens. The StarAdventurer behaved perfectly with no star trails in any of the unguided 90 s subs. So, here is the first result from this adventure, processed in PI and PS on a small laptop screen - I will probably have another go at it when I get back home to my 43" screen.
The Tarantula Nebula (NGC2070) can be seen in the upper left corner of the galaxy. Wiki writes: The Tarantula Nebula has an apparent of 8. Considering its distance of about 160,000 ly, this is an extremely luminous non-stellar object. Its luminosity is so great that if it were as close to Earth as the Orion Nebula, the Tarantula Nebula would cast visible shadows.In fact it is the most active starburst region known in the Local Group of galaxies. It is also one of the largest H II regions in the Local Group with an estimated diameter around 200 to 570 pc and also because of its very large size, it is sometimes described as the largest although other H II regions such as NGC 604, which is in the Triangulum Galaxy could be larger.The nebula resides on the leading edge of the LMC where ram pressure stripping, and the compression of the interstellar medium likely resulting from this, is at a maximum.
Hopefully I get the chance to add more images to this thread soon - the weather report for tonight looks promising.
I was lucky enough to spend Easter in Mauritius and managed to get a night of imaging in despite the tropical night time clouds! As someone who lives in the Northern hemisphere, the Carina nebula has always been a target I've coveted, but during my holiday, I also loved Crux as prominent constellation in the Southern sky. So when I ran into polar alignment issues with my Skyguider Pro, I decided to play it safe and go for a wider field, capturing both those targets rather than focusing purely on Carina as was my original goal.
This was shot from my father in law's rooftop in Bonne Terre, Vacoas, Mauritius and my basic polar alignment meant significant field rotation, but I still got some usable data. Cropped, processed and finally upsampled.
Data was shot at f/2.8 with a 50mm lens, unguided on an unmodified Sony a6500. 174 lights at 30 secs each = 1.4 hours of integration. Bortle 5.
From the colours it looks like these objects sit right on the disc of the Milky Way and I know there is more in the picture I haven't mentioned!
Thanks for looking!
A photo of the Carina Nebula taken using a 8" SCT at F6.3 (1280mm focal length) with a Astro modded Canon 40D, ~59x39 arc-minutes FOV.
During an imaging session of Eta Carina close up, one sub on 9th March had an extra star on it, only lasted for a few minutes at most and vanished. I suspected either a GRB, CR or perhaps a Shock Breakout.
In between the meridian flip of imaging another object, I slewed the scope toward the Carina Nebula to see if the point of light reappeared... if it was a SB than perhaps there was a chance that a supernova would have happened, but no such luck.
The Carina Nebula (NGC 3372) also known as the Grand Nebula, Great Nebula in Carina, or Eta Carinae Nebula, is a large complex area of bright and dark nebulosity in the constellation Carina. The nebula lies at an estimated distance between 6,500 and 10,000 light-years from Earth.
Total exposure time was 1 hour 57 min 30 seconds. Subs captured are 15x30s, 10x60s, 14x150s, 13x300s at ISO800 on 27th March 2018.
This is the photo of the Carina Nebula taken using a 8" SCT at F6.3 (1280mm focal length) with a Astro modded Canon 40D, ~59x39 arc-minutes FOV, to try and verify whether I spotted a supernova.
During a imaging session of a closeup of Eta Carina which I started at the beginning of March, one SII sub (9th March) had an extra star on it, only lasted for a few minutes at most and vanished.
After eliminating noise and/or a reflection, I suspected it to be either a GRB, CR or perhaps a Shock Breakout.
In between the meridian flip of imaging another object, I slewed the scope toward the Carina Nebula to see is the point of light reappeared... if it was a SB than perhaps there was a chance that a supernova would have happened by now, but no such luck. I should get a T-Shirt made that says "I was looking for a Supernova, but got this lousy photo instead." :-D
This is a quickie image that I took to check for changes in the location where I thought I caught a supernova (or some flare) on 9th march that I thought would be of interest to someone.
This was imaged in between a meridian flip of imaging another Nebula near the Carina.
This is through a focal reducer and imaged at f6.3, 1280mm FL using my 8" SCT.
Consists of a dozen 300s and another dozen of 150s ISO800 subs.