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GuLinux

Sumerian Optics Alkaid 12"

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After a long wait (ordered on May, received it on August) I finally received my new baby :D

The scope is the Sumerian Optics Alkaid, 12 inches version (300mm).

http://www.sumerianoptics.com/products-price/

It was ordered from Teleskop Express (DE)

 

It's a bit expensive for a dobsonian telescope, but I was really looking into something very portable.

The "fold into a hand-luggage compliant suitcase" feature is really amazing.

Not many airline companies do actually allow so much weight (16 KG), but still you can find a few, and I'm gonna see what happens on my next trip in Italy in a couple of days.

 

I haven't yet used it a lot, due to weather, moon, and laziness :D but these are my first impressions:

Unboxing

The scope was very well packaged, it was a mess to cleanup the house with all that foam peanuts :D

This of course is all very nice for transport, what was less nice is that all this, and the protective cotton over the mirrors, did create a lot of dust and filaments all over the mirrors.

Nothing serious, cleaned most of it with a little air pump, but they might think of a different protection layer for the mirrors.

 

Assembling

The first time you read through the provided manual, get it wrong on a few steps, but overall instructions are clear enough, and most of the pieces can be mounted in one way only, so it's quite straightforward.

Mounting the suitcase back requires some attention too, but there are instructions for this as well, so it's easy.

After doing it a couple of times, you can really assemble and disassemble the whole thing in a matter of 5/10 minutes.

 

Collimation

This is where I'm still having some problems. Some of them due to the scope it self, but some might also be because of my inexperience with it, and with the Cheshire tool (I was previously using laser collimators on smaller newtonians).

The secondary collimation is quite straightforward. I'm still having some minor issues in aligning it to the focuser, but with more experience it should get better.

The primary is what troubles me most. Both the secondary and the primary use a two screws system. The third one is fixed, and you should align it by moving the other two.

This in theory should work, but it seems that the two screws don't have enough run to compensate for major misalignments.

Also, the screws movement is quite irregular, and after a few tries, one of them became very very hard to move. I will try again using some grease, otherwise I might think of replacing them with some plain old allen keys.

 

Movements and stability

Movements seem to be quite smooth. The scope is also provided with a shock cord "counterweight" system for balancing heavier eyepieces. I don't have any (yet), but I'm planning to buy a 1KG ep with a big FOV, so I tested balancing with a 1KG counterweight attached to the focuser, and it seems to hold on quite well. I also bought a third shock cord in addition to the two provided, just in case I need more traction.

 

Red dot finderscope

Mixed feelings with this: it certainly looks nice, and it also has a green setting (for daily usage/bright objects I guess?).

But to align it you need an allen key (included), which feels a bit uncomfortable, and the window doesn't seem clear enough, blocking too much light, so it's a bit difficult to point at faint objects/stars. The finderscope is also too close to the tube, so it's not very comfortable. I will have a few more runs, and then decide if I want to replace it with a different one (I have a Celestron Starpointer Pro, which I have used with quite some satisfaction).

 

Light shroud

There is a little shroud provided, but honestly I haven't even tried it, I really didn't like the idea of an open truss.

Instead, I sewed a full length shroud using some lycra cloth. I added some magnets to the top and bottom of the telescope, in order to keep the shroud in place.

 

First light

I had a quite unlucky first light, actually.

There was too much dew, and the moon rose slightly after 11 pm.

I just made it to view a couple of objects (easly resolved polaris b, the ring nebula), but the eyepieces got quickly covered with dew.

In a way that was also useful though, since I both tested that my light shroud protected quite well the primary mirror (no sign of dew in there), and the built in anti-dew of the secondary, that in 5 minutes cleared it out.

 

Overall impressions

I still have to familiarise with it, particularly with the collimation, but I am really satisfied with this setup.

The portability side is quite amazing, I could put it in the back of a quite small car, with lots of room to spare!

 

I'm looking forward to a few more detailed tests over the next few weeks, in a fairly darker spot. I'm a bit worried about the airplane trip, but we'll see about that... :)

 

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Your interested public demands photos! :icon_biggrin:

 

Very interesting first report.  Look forward to reading more about your experiences with it.  As you say the weight is a bit much for airline cabin transport, but the idea of a 12" scope that could go to a dark site is a very intriguing one...

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32 minutes ago, DirkSteele said:

Your interested public demands photos! :icon_biggrin:

Will do :)

32 minutes ago, DirkSteele said:

Very interesting first report.  Look forward to reading more about your experiences with it.  As you say the weight is a bit much for airline cabin transport, but the idea of a 12" scope that could go to a dark site is a very intriguing one...

Well, there are a few airline companies that allow "as much as you can lift" (easyjet) and up to 23 KG (BA).

I'm much worried about airport security, though :( 

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Yes pictures please. I have an 18 inch made by Michael (Sumerian) and it's a fantastic scope, I always found him helpful too, TS I have not had so much fun with though.

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Another satisfied Sumerian Dob owner here (16").

The primary collimation can be a pain but I would seriously advise you do not replace the adjustment thumbscrews with allen bolts. If the allen key slips (and it will), it's only going to land in one place and you don't want that!

Another tip to help collimation, if using a laser, is to push the mirror cell underneath gently to see which direction to adjust the primary as you'll see the reflected dot (cross in my case) move on the secondary.  Also, do this with the scope pointing low down.

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Thanks for the tip.

Fortunately I just found out what was wrong with my thumbscrews: when I first tried the collimation, I probably did tighten one of them too much.

As result, the little nut that's between the mirror cell and the support go tighten too much as well, basically creating loads of friction.

 

IMG_20170814_205953.thumb.jpg.702eac2e2ca14c811b7f85199b86f85c.jpg

Just loosening it a bit had a massive improvement.

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I love my Sumerian too, if only I could get a chance to use it :) Hope you get some more opportunities to try it out soon, I'm sure you'll get some great views.

 

Edited by Scooot
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Congrats on the new scope :thumbsup: The Sumerians are beautiful looking, and very clever compact designs!  Will be interested to hear how you get on + pics please :)

Best of luck,

-Niall

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Well, this is a first "preview": telescope close to my luggage and laptop backpack. As you can see, it's just slightly bigger then the latter (although much much heavier... almost breaking my hands... I need to add wheels :D )

I was expecting troubles at the security checks, but surprisingly they didn't even ask me for further inspection.

Ready to go :headbang:

L'immagine può contenere: persone in piedi e spazio al chiuso

Edited by GuLinux
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I found some unpacking/first light pictures, I forgot they were in my girlfriend's phone :p

IMG_20170803_173149.thumb.jpg.b3d0b553bede133baf596b6d83443624.jpgIMG_20170803_175308.thumb.jpg.ed2bca7264bcfff29aa8800c51b4d265.jpgIMG_20170803_175620.thumb.jpg.9bcdccbdca77fc6a96f3f803678de410.jpgIMG_20170803_181531.thumb.jpg.b17e14ea853e054c4716e889b04044cc.jpg

IMG_20170803_182806.thumb.jpg.de9686f145432020b10eb5047f560f2b.jpgIMG_20170803_182753.thumb.jpg.6ffee72d07779fffb3ee3add044e38d8.jpgIMG_20170803_183535.thumb.jpg.e63fc22c3c19cd582d1c4634e2c3422c.jpg

IMG_20170812_201925.thumb.jpg.16014b65b20e29750b5f63d591dcc21f.jpgIMG_20170812_205359.thumb.jpg.6d425b4f14dfa7681fefe6bf2fbe77ce.jpg

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There has to be more feedback on this one. Cmon! How's the mirror? Do the DSOs pop? How is the primary fan working? How smooth is the hand tracking at high powers?

Edited by BGazing

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Sorry for the delay. I really haven't used it much, mainly because of the weather.. :(

I just took it to a 5 days trip to the Alps. Quite a dark place, although the weather wasn't that great there as well.

The mirror is pretty good, particularly for being a simple GSO optics. I was able to spot Stephan Quintet, although I didn't resolve all the components. Brighter objects are very enjoyable, and the scope does feel quite "bright". I was used to a C8 for visual observing, so you can probably guess it's a nice upgrade for me.

I haven't tested much the primary mirror fan, just one time I think, since I never really had temperature problems on the primary mirror, which I guess it is a plus.

The movement is actually very smooth, and the bunjee cords system is an excellent solution to counterweight bigger eyepieces.

Another plus is the assembly, it's really quick once you get used to it.

A couple of minuses:

 - After some time, the closing locks are getting more and more slack. I'm getting a bit worried they might open when transporting it, so I'd better hurry doing some maintenance  soon.

 - Collimation is really a mess. I really can't see why they insisted on 2 screws only instead of 3 for both primary and secondary mirrors. Adding a third screw on the secondary was very easy (I took one from the included small shroud, which I replaced with a full sized shroud from the beginning anyway). I'm going to add a third screw to the primary as well, as soon as I find one of the correct length.

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10 hours ago, GuLinux said:

Collimation is really a mess. I really can't see why they insisted on 2 screws only instead of 3 for both primary and secondary mirrors. Adding a third screw on the secondary was very easy (I took one from the included small shroud, which I replaced with a full sized shroud from the beginning anyway). I'm going to add a third screw to the primary as well, as soon as I find one of the correct length.

I found that on mine too, and have added a 3rd thumbscrew on the secondary, which makes it much easier.

I haven't on the primary yet, because I don't think it's needed if the scope isn't moved about much.

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Oh my oh my, what a fine scope you have.

Are the pictures from Italy, looks an interesting spot.

Your thread has just fed the I want a dob monster again though.

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31 minutes ago, Alan White said:

Oh my oh my, what a fine scope you have.

Are the pictures from Italy, looks an interesting spot.

Your thread has just fed the I want a dob monster again though.

https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F302858169218

....whistling innocently to himself.... ;) 

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Sale is nothing to do with me by the way, I just noticed it a little while ago.

I have just joined a similar club which is exciting, I will post about it separately when I get the chance to take some pictures.

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Yup, it's indeed a very nice scope.

I'm still on my way doing  a few little mods to improve usage even further.

I added a plate for the Rigel QuickFinder replacing the original finderscope, plus an additional finderscope base for a generic one.

I also added ball castors to make transportation easier, not so sure about them though, they're very noisy.. We'll see.

 

Here's a timelapse of the scope assembly:

 

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4 hours ago, Stu said:

Sale is nothing to do with me by the way, I just noticed it a little while ago.

I have just joined a similar club which is exciting, I will post about it separately when I get the chance to take some pictures.

Naughty, naughty Mr Stu, you must not put temptation in my way........ ?
Thankfully its beyond my means at the minute, so tempt as much as it might, I will resist.
I will resist.
I will resist.
I will resist.
I will place it on my watched list............

 

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There are currently two threads on Alkaid 12, the other is mostly about various mods (here), so I will chime in in this one.

My Alkaid 12 has just arrived. F5, Quartz mirror. So some impressions...after just one assembly in my study. No first light yet, sorry, weather is terrible.

It really is compact, unbelievably compact and clever. Perfect portable little godzilla. Assembling it, I feel, will be snappy once I get a hang of it, disassembling is unbelievably fast.

Its stable and smooth. Compared to what? Compared to SW flextube 12s (two of them) which I perused, it feels actually solid with considerably less flexion. Not to mention the wonderful Moonlite focuser. I inserted laser, roughly centered it on the primary, moved it around...nothing, nothing moves. Perhaps I am doing something wrong :). Paragon 40 causes no balance problems. Will revisit this matter once Paracorr arives. 

Truss tubes feel like you have to 'find' the proper pairing. Some combinations look not so straight. I could be wrong...but the are sufficiently rigid, I feel.

Unlike the photos on the website, there are actually three primary cooling fans. Neat.

Mounting secondary ring is my biggest peeve, feels like RDF is too close to one of the 'slots'. 'Its not a bug, it's a feature', I guess. But I do not like it.

Secondary heater and its packing is really neat. Secondary mounting takes some time to figure out, but once you do it, it is okay. Packing secondary (exposed) gives me jitters, my cassegrain heart fears for exposed mirror surfaces.

One of the pins which holds secondary ring when packing was, it seems, drilled too close to the edge and the wood is chipping, pic attached. Was told by my friends that I should not panic because wood looks durable. The thing is, once the pin falls out packing it would be much tougher.

As @GuLinux mentioned, packing has to be seen to be believed, lots of small styrofoam flakes that float around and attach to pretty much everything. Had to vacuum them to cover my crime before my wife arrives. (You see, I have not bought a new scope, it is just a little wooden suitcase).

photo_2020-01-27_19-25-15.jpg

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Okay, managed two first lights, not at my dark place, but reasonable 20.61 SQM backyard, just to get a hang of the scope. 0 degrees C tests one's patience, and humid conditions are good for figuring out how it will behave under stress.

First, I've contacted Michael re wood chip, he was kind enough to offer to ship it all back so he can make the new cradle (he needed all the parts) but I'll just repair it. He'll ship some novelty of his, truss pole stabilizers. Will post a photo once I receive them.

In the meantime, I was stupid enough to mess with collimating triangle and managed to attach it wrongly. Then peeled it off, attached a new one. Some glue around the triangle and the triangle is again a tiny bit off, perhaps by less than a milimeter vis-a-vis center spot. Gotta say triangle is of immense help when collimating and adjusting in the dark. Not sure how much of a problem that slight off-centering is. I am going to let it be for now, but tips on how to remove it without to having to wash the mirror and whatnot are appreciated. 

Secondary attachment is so far my biggest peeve because it needs twisting around before starting to hit laser near the center of the primary. On the second night I managed to leave fingerprints on the edge of the secondary. So tips on cleaning secondary are also appreciated. 😂

My second biggest peeve is secondary ring attaching. I feel like I am always fighting it a bit, and RDF in the way is not making me like it more. RDF is under review, will see whether it is possible to mount some quick-release shoe and slot in Baader Skysurfer III because RDF needs adjustment after every collimation and doing it in the dark with the Allen key is not really fun. Also Baader has more clearance.

Scope is smooth and works the biz. It is not super stable, so needs to be handled gently. It tracks well and is buttery but if you swing it quickly (as I did) it might jerk and lose collimation. On the second night I had the feeling that it lost collimation once without me being able to pinpoint why. Also, as you might expect, if you collimate at 60 degrees it will not be the same story at 20 degrees and the laser will show it...but that is, again, not surprising.  Here, any tips from the owners are appreciated, but I guess those are the limits of the design.

Fans are silent (three of them, unlike GuLinuxes) and one can observe while running them (no vibration and low to medium powers). Seeing was not that great the second night, so I tried some low power targets (M42, duh, M48, Beehive, Pleiades, Double Cluster, M38, Thor's Helmet). Given that I do my DSO observing normally under much darker skies I cannot easily compare (e.g. Thor's Helmet with OIII is MUCH better in SCT8 at 21.40 than in a 12 incher under 20.60 sky). Of course all of the above are nice in a 12 inch scope. There's some coma, I am still learning to discern coma, collimation, heat plumes and astigmatism of the eye. Work in progress, but not too different from SCT (except for upside down effects of the heat plumes). It was fun, cannot wait to test it at my favorite site, although I feel the biggest problem there will be finding some proper flat piece of ground.

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Here's the update. The pin is fixed (pic attached), with the help of my friends. Michael went out of the way and sent all the tools necessary (although we had them) and, to repeat, he offered to repair everything himself first.

I moved red dot 5mm to the side, as advised by Michael, now it does not interfere with the attachment of the secondary ring. 5mm is really the maximum, one mm more and it would not go in when packing. 

I'd like to think that I am getting better at collimating, but honestly I do not know. What I do know is that it will take quite some time to figure out a quick way to collimate secondary. :)

pin repaired.jpg

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