Hi All, it has been cloudy here in Auckland lately but on Sunday it was a brilliantly clear moonless night so I got a chance to do another test run of the new Serrurier truss scope. I primarily wanted to test if I could prevent dew on the secondary mirror with a large 120mm fan mounted on the side of the secondary cage. I have noticed varying amounts of dew on the secondary on every single occasion since converting to the open truss tube design, so I knew some form of dew prevention was needed. I was very happy to conclude that the experiment was a success with absolutely no dew in sight when I packed up around midnight
Anyway, while keeping an eye out for any dew I imaged Terzan 9 which is a heavily obscured globular cluster in Sagittarius. The cluster actually lies within the Milky Way's central bulge at a distance of 16,000 light years. The magnitude is listed as 16.00.
I also noticed that the position given by Starry Night was absolutely spot on. Some of the positions for these obscure globulars are unfortunately incorrect in various catalogues.
It was unusually windy on the night so I had to keep the exposures a bit shorter than I normally do, otherwise I could see I would loose over half of the frames due to the strong gusts that kept coming. Still I think I got a decent image of this cluster, and again the stars definitely appear tighter than with my old scope. I used to achieve a resolution just about equal to the DSS images, but here the resolution is quite a bit higher.
The image is available here:
http://www.pbase.com/rolfolsen/image/135964114/original
Image details:
62 x 10 s + 116 x 15s
26/06/2011
No filters, no guiding
Hope you enjoy. All comments and critique is welcome.
Regards,
Rolf