[OneCosmos (Chris)]

Friday 19th Feb 13:00

Life is a smorgasbord of experiences and with the passage of time they often fuse together like some complex and interconnected diorama. Every now and again, however, a momentous event takes place that easily stands out as a defining moment; there is a before and there is an after and life is never quite the same again. I count myself lucky to be confronting such a moment on this cloudless day in the astronomy capital of Australia, Coonabarabran. The domes of Siding Springs just 20 minutes to the north west.

We can no doubt all remember the Christmas Eve feeling we had as small children, filled with wonder and expectation of an almost palpable nature for what was to come. You’re doing well if, as an adult, you can once again conjure up that same feeling; I am most definitely lucky today.

‘First light’ through the dream telescope I ordered as far back as September 2019 threatens to take place within hours. The genesis of the scope has taken an eternity to manifest in physical form. There have been a few mishaps (such as Pack and Send losing the mirror only for it to turn up in Cincinnati). A few people other than myself have expended a good deal of time and energy to bring it to this moment, so you’ll have to forgive this indulgent post as I enjoy the anticipation, with much the same level of excitement of those Christmas Eves of so long ago.

First a word about the telescope. The beating heart of the ‘scope is a 28” TechnoFusion sandwich mirror made by the French-Canadian mirror maker extraordinaire and thoroughly decent human being, Normand Fullum. I cannot fault his commitment to this project and his willingness to accept responsibility for delivering the best mirror possible. One of the reasons for the heightened sense of anticipation of this telescope is the promise the mirror holds for superlative results. The mirror test report shows a mirror whose figure barely deviates from theoretical perfection, but as anyone with experience of telescopes will tell you, the test report is only a piece of paper, the real test is under the stars.

The construction of the mirror is different to most telescope mirrors. A typical mirror will be a single piece of glass of varying degrees of thickness depending on the material used, for example Plate Glass, Pyrex or Quartz as well as some more exotic and expensive options. A single lump of glass takes an age to cool down but the best results are only possible once the delta between mirror and ambient temperature is very small. Normand’s mirror has a quick to cool 1” thick top piece of glass, a second bottom piece and, between the two, numerous pillars for support. Air can therefore flow around the mirror helping it to cool down very much sooner than a traditional mirror.

The best mirror in the world however is worthless without a telescope build to match and I don’t think it is too contentious to suggest that Peter Read of SDM telescopes, right here in Australia, can be considered one of the greatest telescope makers of our time, perhaps of any time. His telescopes are a work of art and in fact Peter devoted no less than 450 hours to making my scope. That’s dedication to quality control.

It seems to be something of a tradition that SDM telescopes have a name. The name of mine came to me very easily because I was looking for something that could bring together my two passions of astronomy and music. The scope therefore has been christened ‘Nocturne’ which literally means ‘night song’ so it is more than apposite. For the non-musicians, a Nocturne is a musical form made famous first by the Irish composer John Field (1782 – 1837) and then taken up by the far more famous polish composer, Frederick Chopin (1810-1849).

Today Pete and I are also joined by Matt Saarikko who is now the owner of my much celebrated (by me at least) APM/TMB 152mm LZOZ triplet refractor. Matt has many years of experience in visual astronomy and knows a good mirror when he sees one.

Before dark we knew there was much to do.

With some ceremony, the rocker box emerged from Pete’s trailer. Once the awe and wonder at the sheer beauty of the rocker box had been absorbed, I had a nasty sinking feeling because something told me this would never fit in my trailer! But how can that be? I had measured the distance between the wheel arches a hundred times and purposefully relayed those to Pete so he could be sure he would ensure his design would meet the strict physical requirements. It didn’t take me long to realise where I had miscalculated. My motto in life (usually) is to never make assumptions, but on this occasion, apparently, I did make one that nearly proved disastrous. I had spent so much time focussing on the limitation of the gap between the wheel arches that I had completely missed the fact that the width of the door opening was in fact smaller and, holding the tape measure with some trepidation my thoughts were confirmed – it would not fit through the door!

Fortunately, there was a solution at hand, which meant removing the wheels and changing the configuration from one wheel either side of the axel to putting both wheels on the inside saving just sufficient space to get it through the door. Just for fun I tried to push the 140KG rocker box manually up the ramp, but not being Conan the Barbarian, it was simply impossible. Thank goodness I had the foresight to include a winch in the trailer, which made extremely light work of pulling the SDM up the ramp as though it were a trifling nuisance.

Surely there would be no more problems? Wrong. The ground clearance on an SDM is about the same as a formula 1 car so that ascending the two-piece hinged ramp resulted in it becoming ‘beached’ on the springs. A hefty shove overcame the 1mm obstacle and then it was plain sailing. I’m lying. The top of the ramp was a far more serious problem because the floor of the trailer is about 30mm lower than the top of the ramp and even with a nicely bevelled aluminium flap bridging the gap it once again became stuck, this time far more convincingly and it required the might of at least two of us to lift it over the obstacle. Clearly this would be a problem, especially if I were on my own.

One expedient but onerous option was to accept that I could only ever use the scope after de-coupling the trailer from the car and winding up the jockey wheel to the maximum thus forcing the trailer to tip up slightly to favour the scopes descent.

(The first thing I did on my return was to take the trailer to a place that could make the modifications required).

…………………….

Friday 19th Feb 21:00

Obviously, you can’t assess a telescope or its optics whilst the moon dominates the sky and Peter, Matt and I are all seasoned observers who readily acknowledge that fact so we wouldn’t dream of viewing with the moon up would we? We observed in total defiance of the moon. Sure, there would too be a few hours after midnight with more favourable skies as the moon lost its potency to destroy the darkness, but adrenalin only goes so far and, after a 10 hour drive we were keen to observe with whatever limitations we had to accept.

We did in fact wait until sometime after the sun went down to set up though, which meant that my first solo assembly (with Pete laughing on the sidelines) was done in the dark! Nevertheless I did successfully complete the task.

This was first time using Pete’s auto-collimation method. With my previous 16” I used to have to do collimation in two steps, one at the top and one at the bottom. Now both can be done at the top and it’s a breeze. Following this, I moved the scope to the vertical position to begin the 2 star alignment before moving on to the first target.

The moon was still high so Omega Centauri seemed a sensible choice. Dobs are made for globular clusters and it didn’t disappoint even though after 10 hours in a hot metal oven trailer the mirror temperature was very much higher than the more rapidly falling ambient temperature. In addition seeing was average at best with all stars scintillating more than I typically see.

Moon notwithstanding we could hardly avoid the nebulae. The Tarantula was first off the ranks and my goodness what a sight with the 21mm Ethos (and SIPS). It was only a single eyepiece but looked really quite 3D. The intricate details in the nebula were beautifully presented with lots of faint stars through the gas. One surprise was that switching to the Nikon 17mm it came to focus. All the reports on IIS and Cloudy Nights say this eyepiece will not come to focus with SIPs, but as Peter pointed out, most makers position the SIPs according to Televue’s doctrine, but the SIPs doesn’t need to be placed so close to the secondary and that allowed the Nikon to reach focus easily and room to spare. It is a magnificently sharp eyepiece.

We took a view of Cantaurus A galaxy and although it lacked a bit of contrast due to the moon, all the structure was present in the view.

Eta Carina was magnificent although with this size scope even the 100 degree view of the Ethos doesn’t provide the expansive views I got through the 16” but the detail was fantastic. Again, billowing gas clouds littered with faint stars was worth viewing even with a hot mirror, a moon up and poor seeing. On the right night this will be a fantastic telescope.

The second night was cloudy – well actually we went to bed when it was totally clear hoping it would turn cloudy to make us feel less bad about the decision (and it did go cloudy), but we couldn’t stop up until 04:00 as we both had a long journey ahead of us and I have, hopefully, many years to enjoy the scope. So much more awaits.

I look forward to showing all those within reach of Brisbane through the scope at some point.