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Sumerian Optics


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I'm lucky enough to live in deepest, darkest Cumbria, but unfortunate enough to live in a village with more streetlights per head of population than anywhere on the planet. That might not be strictly true, but for a village for a population of fewer than 250 people, it's a bit annoying that my back garden is lit up with 8 orange streetlights. I've normally had 8-12" Dobsonians, and on clear nights would pop it in the back of the car and drive a couple of miles to a green lane which is far from any artificial light. However, I wanted something more immediate, and that I could take just half a mile, on foot. So I started looking for a grab and go refractor set-up. I was worried though that the massive reduction in aperture would always frustrate me, and greatly outweigh the convenience of its portability. Then someone mentioned a telescope maker in the Netherlands called Sumerian Optics. Michael of Sumerian makes a variety of great looking truss dobsonians, including a version which weighs less than 10kg for a 10" version and packs away into a case measuring 15" x 12" x 5". That includes a primary fan, finder, red dot finder and secondary heater. So I ordered!

5 weeks later, it's arrived, and whilst I've only had a quick peek through due to cloud, and the scope was very roughly collimated by eye, I know the optics will be good as I opted for Orion Optics 1/6pv mirrors. The movements however, are silky smooth and my second time assembling it took less than 15 minutes.

Anyway, this isn't a review, so here are the photos.

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I think that's something that's going to be worth their while sorting fairly quickly.

You can run the dutch pages through babelfish, or email the owner, Michael, who's very helpful....and patient! I had many questions! By the way, you can have any colour you want.

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True that, I think it would help. My very limited Dutch was enough to navigate around though. Will have to have a look again maybe with a translator too.

It all looks really nice, one of those times when you really want something but don't really need it. Will definitely remember this site for future reference.

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Oh, I've got an honours degree in justifying things I don't really need. What I did with this one was decide that for my son's education, we needed a grab and go scope. So I decided that as education is the most important gift you can give a child (apart from an xbox) that I should buy a Televue NP101. However, on finding the Sumerian Optics site, I realised that not only could I get something much bigger, but it would also be several thousand pounds cheaper. So, when my wife asked how much it was, I could tell her that, in all honesty, I made a profit of £2500 by buying it.

Clever eh?

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Superb looking instruments at quite a competitive price too,

Write out 100 times

I MUST NOT BUY ANOTHER TELESCOPE

I MUST NOT BUY ANOTHER TELESCOPE

I MUST NOT BUY ANOTHER TELESCOPE

I MUST NOT BUY ANOTHER TELESCOPE

I MUST NOT BUY ANOTHER TELESCOPE

I MUST NOT BUY ANOTHER TELESCOPE

I MUST NOT BUY A...........................

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Wow! That's a beautiful scope. Man I can feel the desire for a compact truss tube building.

I'm curious about the secondary mirror. I don't mind tweaking the collimation of the primary using a barlowed laser because that's easy, but secondary mirrors are really fiddly - there are so many degrees of freedom. How does the secondary connect to the spider and how easy is it to get it lined up?

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That is a nice looking 'scope and to have one with such a large aperture and yet be so portable must be amazing. It looks like the truss tubes would be the bulkiest component but not overly so. My eyepiece case probably takes up more space than that 'scope collapsed down :glasses1:

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Aye, the trusses don't fit within the case, but what I'm going to do is simply keep them connected and carry them about in an old drawing tube I had from the days when us landscape architects used to draw on paper. They're only about 8mm in diameter though and weigh next to nothing. The trusses do splay-out from the primary to the secondary, while I imagined they'd be parallel. I don't know why I imagined that though!

My son and I have been pondering how to carry this about to our favoured observing site. It's less than a mile away and is half tarmac to the edge of the village and then grass paths with just a couple of stiles to negotiate. It might be that one of us (me) carries the optical "tube" with bearings while the other carries the base. Or we might simply (and probably) pack it away as designed and reassemble in location. I'm SO glad I didn't opt for a 3" refractor, and I'm not even sure a 3" would have weighed less. It would certainly have been more cumbersome.

I'm curious about the secondary mirror. I don't mind tweaking the collimation of the primary using a barlowed laser because that's easy, but secondary mirrors are really fiddly - there are so many degrees of freedom. How does the secondary connect to the spider and how easy is it to get it lined up?

Well, remembering that I've not really had a chance to observe through it yet, and that I might be doing it wrong.....the secondary has a spindle on it which sits in a recess on a small disc in the middle of the spider. It then stays there thanks to a very strong magnet and what I do is rotate it until I can see it's lined up with the primary through the focuser...just like a normal Newtonian. There's no backlash at all. Then, with my laser (or I imagine a Cheshire) I ensure it's pointing at the middle of the primary with the normal three adjustable screws, but made easy through being three knurled knobs. I had the whole scope aligned (according to my HoTech collimator) in around a minute. Next time I have it assembled (so next time it's clear, which might not be any time soon) I'll take some close-up photos for you.

The one thing I'm going to have to learn to live with is seeing all the little dust flecks and marks on both mirrors and get over it! With a normal Newtonian, they're tucked away so you only really see any marks or flecks at night if you shine a torch down it. With this one, they're there, right in front of you! I did take delivery of an Astrozap cover this morning. Having measured, I opted for the model designed for 6-8" Dobsonians, but frustratingly it's a bit too tight around the bearings by no more than an inch. It's perfect for the optical path itself, but won't quite cover the base. This might not matter, but I'll see if the Widescreen Centre will let me swap for the 10-12" model, although this will be about 18" longer than I need.

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Jao, Looked at the site a while back and the scopes are very nice but the prices are without the mirrors and focuser. They come extra.

You buy the size of bare scope you want and then get the mirror and bits as additional items. So maybe not so competitive.

Worked in Holland for a few years so learnt to read a bit and the lack of "optics" was a bit obvious.

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Hi Capricorn, yes I did realise that they list the structure price without the optics or the focusser! Google does an OK translation.

I should have made it more clear in my original post suggesting that these scopes were competitive, I was comparing to other commercial lightweight highly transportable instruments like the Obsession UC.

Supplied to the UK, including shipping and taxes I was quoted £4,200 for the 15" UC. The Sumarian 14" Alkaid, shipped with taxes and including an Orion Optics mirror will come in at around £3,300.

I agree that compared to a more traditional design dob this is expensive, but compared to another ultra light dob I do think it is a good price and competitive.

I guess these scopes are for a particular market where the buyer is looking for something that is easy to store and transport, so not every bodys cup of tea. But if you want that scope to take on the family holiday to the south of France where space in the car is at a premium they look good to me!

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I paid just shy of £1000 for my scope. For that I've got a 10" scope with very high quality mirrors which I can carry to pretty much anywhere I can walk to.

When you add up the cost of something of above average quality and a mount, in the grab and go refractor market, you very quickly get up to that amount of money, for something just 3" in aperture.

I know it's like comparing apples and pears, but with the criteria I had, this offered massive value for money.

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