As a result of my primary mirror now being 17 years old, and never having been re-coated, I decided to replace it. I could have it re-coated, but that would mean shipping it overseas plus paying for the coating and the return shipping. And then I would be without a mirror for a while...
Instead, I applied for funding from the
Kingdon-Tomlinson Fund and the Auckland Astronomical Society. And now together they have generously approved to fund my purchase of a Royce 12.5" f/4 conical mirror
This is really all thanks to my Beta Pictoris image from last year. I have been very fortunate to get to know the good people of the Auckland Astronomical Society and in particular Dr. Grant Christie. This has been very rewarding and since December 2011 I have been invited to give talks on Beta Pictoris and image processing to both the Auckland Astronomical Society, Tauranga Astronomical Society and latest at Auckland University of Technology.
I also picked up my first awards recently by winning the Scientific and Deep Sky sections of the
2012 Harry Williams Astrophotography Competition. In addition I also won the Beaumont Prize for writing, for an article about... you guessed it: Beta Pictoris
So now I'm building a larger scale version of my Serrurier truss Newtonian to house the new mirror. This is the same design as my
10" Serrurier truss Newtonian build from 2011 (See also this thread:
http://www.iceinspace.com.au/forum/s...ad.php?t=74690).
12.5" was the largest I could fit in the observatory since I didn't want to go too low on focal ratio. Also, I want to keep the weight at a minimum because my current setup is tracking beautifully. For this build I'm applying some weight savings here and there and I hope the 12.5" OTA with a conical mirror will weigh more or less the same as the old 10" did with a standard mirror.
So far I have completed the main structural elements: Upper cage, central brace and mirror cell. I'm now working on the details around the secondary holder and wire spider.
The mirror is expected to be ready in January. In the meantime I aim to finish everything else and just leave the trusses to be cut to the correct length once I have the mirror and can balance the OTA properly.
Check this gallery for all the images. I will add images there as the build progresses:
Link to image gallery of the build so far
I will post more updates when there is some progess.
Regards,
Rolf