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Walking on the Moon

The Universe in a box....


Stu
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This is a bit of an observing report combined with a bit of an equipment review. I’ve been a bit ‘acquisitorial’of late, some items that came up for sale in an awkward order but I’m happy with what I have got at the moment and may rationalise again in future once I see what I use.

The scope is a Sumerian Alkaid 14” Truss dobsonian with a John Nichol mirror. My back is pretty shot, so man handling a big dob is not something I can or will be able to do. This scope packs down into a perfectly manageable box with a handle and goes easily into a small corner of the boot of my car. It will easily go on a trolley to take it distances to a site too if needed.

The only part that doesn’t go into the box are the Truss poles. The scope represents quite extreme ultra portability, with inevitable compromises but for me it is about being able to access some decent aperture under dark skies in a way that I find fits into my lifestyle and capabilities. The design is very clever and much thought and effort has clearly gone into getting it all to function well whilst fitting into the compact storage box.

My club had been wanting to do a dark sky trip for some time, and we somehow managed to get organised to plan in a couple of possible dates for this new moon. The forecast looked promising for Friday so we decided to head for Bignor on the South Downs which can offer skies of mag 21+. I work near Dartford, so headed straight there after work, arriving at around 7pm as I wanted plenty of time to set the scope up as it wasn’t something I had had a practise run at.

The pictures hopefully tell a thousand words. Basically it is a case of unpacking the box to see what is what. The base of the box remains as the base of the dob, with the Az axis built in underneath it. I then screwed the Truss poles together to get that job done, very easy. They are very lightweight so I did have some concerns about rigidity which turned out to be unfounded.

Next step was to bolt the alt bearings onto the mirror box. This turned out to be a bit of a nightmare as the holes in one the bearings do not line up with the threaded inserts in the mirror box which is frustrating and hadn’t been pointed out to me when I bought the scope. The fix should be simple ie enlarge one of the bearing holes very slightly but for last night I could not fully tighten down one of the bearings so it was slightly out of line so the alt axis was a bit stiff.

Putting on the Truss poles and the UTA was very simple and quick, the clamping thumb wheels working effectively at both ends. There is a built in RDF which stays on the UTA even when packed down. My biggest concern all along had been collimation as the secondary has to be removed and refitted every time the scope is packed away/assembled. I am sure that with some minor modifications the process can be made easier than it was and a better alignment possible, but still, using a fancy collimating eyepiece (which shows concentric rings to help align the secondary) I was able to get it reasonably centred and round. I had also bought a Hotech laser collimator which made finalising the secondary and aligning the primary quite easy. The Sumerian has two collimating knobs at the front of the mirror box so you don’t have to reach around the back, very easy.

I adopted a ‘good enough’ approach last night, wanting to get maximum observing time and knowing that I was more interested in low power observing of nebulae where collimation is a little less critical. Practise, and refining mods will make perfect in future.

Balance is managed by an elasticated cord system which generally works well. It is a quick process to add or reduce tension, but still, managing a heavy 2” 30mm grenade in the focuser when low down to the horizon was too much so I need some stronger cords I think. Finally, the Moonlite focuser is smooth but not tight enough for my liking, I could not find out how to adjust it last night, need to check this in daylight.

Bignor is a nice site to observe from. It is quite exposed but has a reasonable southern horizon, not perfect but fairly good. The skies were clear and transparent last night apart from some occasional light cloud coming through. Depending on which SQL-M we used it got down to between mag 20.8 and 21.1, I suspect more towards the 20.8 end, not sure why it was not as dark as last time we came which was 21.3.

So, observing! With the naked eye, the Milky Way was very prominent, particularly my favourite part around the Cygnus Rift. M31 was relatively easy with the naked eye, and looked huge with averted vision. The DC was equally obvious, but M13 was out of reach, skies not dark enough. That said, through the night we saw numerous satellites, and some lovely meteors, some leaving trails.

I decided to be gentle in terms of targets for my first session, so many lovely, well known objects I enjoy looking at, so why not just enjoy them with a bit of aperture?

Even before dark, and without any filtering M57 was fabulous, and got better later on as the sky darkened and I added the OIII. Strongly defined ring with the softly filled inner section. Nice.

M8, M20, M21, M17 and M18 were all lovely as usual, although tricky to get so low with the dob. It meant scrabbling around on the floor. Nebulosity very clear and complex in M8, my old style Lumicon has fabulous transmission levels and great contrast.

M11 was a stunner. It really does benefit from some image scale, the V shaped lanes clearly running through the ‘flock’ of stars.

Equally stunning was Peter’s suggestion of Caroline’s Rose, one I often overlook. Like M11, the image scale and brightness showed it off beautifully, the dark lanes swirling in the stars giving it a truly rose-like appearance.

M31 showed me one of its lovely dust lanes, a first for me really., whilst M32 was clearly a Galaxy, not a fuzzy star, and M110 had a nice oval shape to it.

M27 was huge! I’m more used to a faintly apple core shaped object but in the Sumerian it was far more oval, the outer shells filling in the shape more that I’ve seen before. I had to up the power to get some definition of the classic Apple core shape whilst keeping the outer shells, the 20mm APM doing well here. What is clear is that I need something ultra wide in 13mm too :shocked:

M13 looked incredible, so much resolution into the core. The propeller was visible, just about, but for some reason it didn’t jump out at me. Perhaps I should have tried more power? For some other reason I just could not find M92, despite several valiant attempts!! No idea who had stolen it!

M71, very nice loose globular, more like a tight OC

M15 was a cracker too, a tight,  brighter core fading noticeably out to the edges, nice resolution still despite the smaller size than M13

I caught M51 earlier on, two cores clearly visible and the haloes of the spiral arms there too. It was not fully dark at the time, and when I tried later on the transparency in that area seemed to have dropped off so it was worse. To be revisited. M101 was elusive for the same reason, and whilst I caught M33 it was not a particularly stunning view, in a brighter part of the sky. M81 and 82 made a nice pair but again, I will revisit them when they are better positioned.

Uranus and Neptune were picked off fairly easily by star hopping and referring to SkySafari. Uranus a tiny disk, greeny grey if anything. Neptune even tinier and bluish to my eye.

Later on I picked up Comet 21P down in Auriga once it got high enough. Quite clear and easily found, showing signs of elongation into a tail. Hopping around the area gave me M36, 37 and 38 which looked good, will be better when higher.

I guess I’ve held off the stars of the show for me. The NAN is too big really to enjoy in the dob. To me you need a much wider FOV to get the overall shape into view although the nebulosity was very clear, and the Gulf of Mexico region well defined in the 30mm eyepiece.

So, almost inevitably the Veil and the Crescent were my two favourites. The Crescent was very clearly defined and with averted vision showed some internal structure, the central bar through to V1770 Cyg and the variations in the ‘shell’ itself. Best in the 20mm APM I think, this seemed to be a better view than I had previously with my 16” Sumerian Canopus at SGL10 although that was a number of years ago obviously so memory may not be accurate.

The Veil was beautiful, probably near the best I’ve seen it. Best framed in the 30mm, the Witch’s Broom separated clearly into two with hints of more to come. Pickering’s Triangle really looked like a triangular peak, broadening out towards the bottom of the fov. The Eastern Veil showed real structure, the two hooks at top of the inverted view looking lovely and plenty more nebulosity extending out from here which I had not seen before.

So, no dramatic new targets, just some fairly stunning views of well known favourites. We had a great night, and made the most of what initially seemed like a marginal opportunity. The scope packed down quickly and without fuss into its box to be popped into the car, ideal for me.

The long trek back was challenging from a tiredness perspective, leaving well after 1am and arriving at home at around 2.25 am. The journey was punctuated with 6 or 7 foxes, a badger and an owl that swooped across the road in front of me and needed a jab on the brakes to miss.

Home safely though, a cracking night, and one to be repeated. The Alkaid will be with me in Lucksall, hopefully with teething troubles ironed out :). I have an EQ platform which I may use too to give tracking.

If you’ve got this far, wake up ;) 

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Great report Stu. Again you’ve surprised me by how many objects you observed through the night. 

Thank you for letting me have a good look at the Veil through it - absolutely beautiful. And M13 was pretty special as well. You have reminded me about the ring, dumbbell and Caroline’s Rose  - I must revisit those. 

I agree that the drive back that late is a bit of a killer but at least I had PeterW with me to post mortem a great evening! 

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Very nice report Stu and good first light, as you say, adopting a good enough (initial) approach, great scope pictures and location to. Reading your descriptions, I can quite relate to your target selection applied to a 14" dobsonian, combining 30mm (31mm) eyepiece, high transmission Lumicon OIII filter. Had been clear here, but getting over a heavy cough n cold settled for two pints of orange (with straw) at the pub, eagerly watching for next wk-ends weather reports. Yep the drive home can be sometimes an effort and certainly on the backroads out, all manner of wild life seems to become active, I hope to plan an over-nighter up here, taking a tent and monitor the sky brightness, look forward to your follow-up Sumerian Alkaid reports.

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7 hours ago, Davey-T said:

Sounds a good night Stu, look forward to seeing it at Lucksall, thought you had one of those before or was that an 18".

Dave

Dave, I had a 16” Canopus before. A much bigger scope in all respects, aperture, weight and bulk. It was still an ultraportable scope when compared with some of the serious Truss dobs out there amongst the dob mob, but was just something I ended up not using that often as getting it out of the shed and into the car was quite an effort still. With the Alkaid, it is a simple and quick job which won’t put me off. Hopefully more dark site visits to come this autumn.

This was the Canopus for comparison, much more substantial UTA for a start. These shots were taken at Lucksall during SGL10.

Reminds me, I need a shroud!

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I'm lost in wonder at your report and would love the chance to use my 12" Dob at the site in Bignor.  My light-polluted home in Surrey is only about 45 minutes drive from Bignor.  It looks like an open field but is it private land or a designated observing site, please?  If it's a closely-guarded secret I wouldn't blame you for keeping it to yourself, though!

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33 minutes ago, Relpet said:

I'm lost in wonder at your report and would love the chance to use my 12" Dob at the site in Bignor.  My light-polluted home in Surrey is only about 45 minutes drive from Bignor.  It looks like an open field but is it private land or a designated observing site, please?  If it's a closely-guarded secret I wouldn't blame you for keeping it to yourself, though!

I’ll drop you a pm, always welcome to join us as it is quite remote on your own.

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20 minutes ago, Sunshine said:

that's am awesome dob you have there, where can I get one of those nifty compact dobs?

The company that makes them is called Sumerian. I think they are available through TS in Germany and maybe others. I think 14” is a custom size, they do up to 12” as standard.

I’ve just noticed that they do an encoder retrofit kit which is excellent news, with a Nexus connected to SkySafari finding stuff would be so much easier!

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9 hours ago, Stu said:

So, no dramatic new targets, just some fairly stunning views of well known favourites.

Great report Stu, and nothing wrong with stunning views of known objects.

That is a really beautiful dob Stu, seen them arround on starparty's here in the Netherlands. Very clever build and manageable.

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11 minutes ago, cloudsweeper said:

A great read, Stu. Sounds like all your efforts were very well rewarded!

Doug.

Thanks Doug, yes it was a trek, but well worth the effort. We will go back!

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I’m so pleased your aperture plans have come to fruition, Stu. Really enjoyed the report. Seems like a really neat setup for travelling with.

I can see that propeller in M13 but similarly don’t find it obvious. Perhaps I’m thrown off from seeing it in images?

I can wholeheartedly recommend the 13mm APM HDC. I’ve had it a few weeks now and it’s seeing a lot of use. 

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12 minutes ago, chiltonstar said:

Quite a scope & quite an evening Stu!

What is the actual weight handled (I speak as a fellow back-sufferer).

Chris

Thanks Chris, it was fab :)

From memory it is around 23kg. The 12” is 16.5kg so that sounds about right. I find it an easy one handed lift.

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On 09/09/2018 at 08:08, Littleguy80 said:

I’m so pleased your aperture plans have come to fruition, Stu. Really enjoyed the report. Seems like a really neat setup for travelling with.

I can see that propeller in M13 but similarly don’t find it obvious. Perhaps I’m thrown off from seeing it in images?

I can wholeheartedly recommend the 13mm APM HDC. I’ve had it a few weeks now and it’s seeing a lot of use. 

Thanks Neil. Yes I think the 13mm APM would make a lot of sense. It’s funny, my little orthos are quite happy in my Tak, but somehow the small afov makes them much less appealing in the dob. The light weight is nice though, for balance.

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