First Light Report (well sort of) on my new/old 12" Orion Optics UK Dobsonian

[Moonshane]

This first light report and is a little behind my actual first use but I wanted to give it a good try out and didn't really have time the first time out as the clouds rolled in! This report is therefore a bit of a mix of my first few uses. Sorry but as usual I realise I've gone on a bit. Not very scientific but more a 'user's' guide'.

I bought this Dob off a SGL member and paid £550 for it. This might seem a little steep for a used 12" dob but I took the view that the quality of the OO base, the renowned optics and the slightly longer focal length would mean that the scope would be a good buy and last me a long time. A nice surprise was that it came with a Telrad affixed to it, a friction brake and also new caps for both ends. More importantly, the scope has been flocked internally for most of its length, has a cross-primary fan and one of the thinner mirrors previously used by OO. This means that it cools down surprisingly quickly with the fan on and I have run the fan constantly on the few occasions I have used it. There is another nice modification which is a small drilled hole on the opposite side of the focuser which allows a pin to be inserted so that you can ensure the focuser is completely centrally mounted from time to time.

An addition made was a new 'retaining ring' which is basically a single OTA ring fitter on the inside of the bottom of the two rings. This performs a couple of important functions; 1) It allows the tube to be turned if required without the tube dropping down. This ability to turn the tube (and indeed add tubes from other manufacturers of the same diameter) is another feature of the OO dob base - most dob designs do not have the facility to turn the tube and therefore if you find the designed angle not to your liking you cannot do much about it. 2) It adds a little weight to the bottom half of the tube. This enables you to move the tube slightly upwards which gives more flexibility when adding weight at the top end with lenses etc.

My first impressions (having never actually seen a 12" Dob before I visited the seller) were 'wow, this is awesome'. This view has not changed at all since.

The tube itself is surprisingly light. I am tall (6'3") and reasonably strong but find it is easily lifted off the base and carried into the garden. For carrying purposes, the design is excellent (although this may be 'accidental/incidental'). There is a cradle with rings and so called trunnion blocks which allow the OTA to be picked up at the balance point by very sturdy fixings. I usually lift the tube off the base, stand it up and the after carrying the base outside, then carry the OTA out and set it straight onto the mount. I then let then fan do its job and within 45 minutes to an hour I can be viewing - not bad for such a large dob from what I read. Actual set up time is about two minutes - i.e. the time it takes to carry the OTA and the base the length of the house.

I was originally going to store it in the shed to reduce cooling times, but paranoia about theft, dirt and bugs, and the fact it is so easy to carry and has a small footprint, as well as the quicker than expected cool down times from 'warm', mean that I have no issues leaving it safe in the house.

As with most people probably, one of my first targets was the Orion Nebula. This was really lovely though the viewfinder and with a 14mm Televue Radian eyepiece I was able to see E, and F (just) in the Trapezium with direct vision. These are much more readily seen when using my newly purchase 2.5x Televue Powermate. With the 18mm Radian the nebula seems to go on forever and there's a lot more detail than I have seen before. I also found another small patch of nebulosity lower down than M42 and am still trying to work out what this was. A word of warning when using the Powermate; it sticks out a fair bit with an eyepiece in and be careful not to smack the side of your head on it - this will do you or your equipment no good at all - yes, I am speak from personal experience!

I then decided to try and split some stars. Obviously most were easy targets but Castor, Polaris, Rigel, Mizar and the two doubles in Orion's belt were very nice indeed. Double stars and planets are not generally what this scope is designed for but being inexperienced, I find the faint fuzzies still hard to track down.

Mars was excellent with far more detail than I have seen previously - the main ice cap very obvious as was a fair amount of greenish 'mottling' on the main disc - sorry for the rubbish terminology. Later in the night Saturn eventually appeared. Simply stunning with at least four moons visible as well as great detail on the rings; the Cassini division was obvious with the 18mm Radian in the Powermate and even more so with the 14mm Radian although you lost a little definition on the planet disc at the higher magnification. Some darker bands were noted on the disc itself.

I have found that the combination of a Telrad as well as a 90 degree 6x30 finder brilliant for locating targets quickly and with no fuss/less neck craning, even when using quite high magnifications (when I cannot be bothered taking out the Powermate and 18mm Radian for example, to then use a 'finder' eyepiece and then put everything back. This gives magnification of about 220x and personally I am really impressed with this. It really makes the initial fine-tuning of the finders worthwhile.

The dobsonian design really does what it says on the tin. Very easy to set up and use with intuitive pointing and with the wider angle/field of view of the Radian series (60 degrees) very easy to keep targets in view even at high magnification. I find that getting the image in one side of the view and then letting it drift slowly across is the most enjoyable method. The ease at which things can be found and tracked was proven recently when I was just scanning about near Ursa Major with my 24mm Panoptic (67x) when a small satellite (not visible to the naked eye) zipped across the view. I put the scope to where I thought it should be and there it was. Despite it moving very quickly, I managed to track it for maybe 30 seconds or more until it went out of view. Based on this, I should be able to manually objects at high magnification eventually.

Even with a long 1600mm tube, a chair to observe is essential in my view as I have to stoop to view even at the zenith. I have made a Denver Chair out of odds and sods - will make a better one eventually I think but it works a treat for now.

In terms of collimation, I do this every time I observe and use the barlowed laser method. This takes just a couple of minutes each time as it's generally quite close. I did some practicing on a smaller 6" Celestron Newtonian which I sold in part to pay for the dob so hopefully have it pretty well sorted now.

Although I still really love my Celestron OMNI 120mm Refractor (which is also a 'keeper') I am now a big fan of Newtonians and dobsonians in particular and Orion Optics UK dobsonians specifically. I'd strongly recommend anyone looking to get the most out of their available time to try and look through a large dobsonian. The larger aperture increases the resolution and allows things to be seen in much more detail that I have seen before. Being still pretty much a starter in this hobby I can genuinely urge anyone to not worry about collimation - this can be picked up quickly or the size of these scopes - just get the largest you can handle. For me the views I have had in the short time I have had this scope have been better than anything I have tried previously. I think it was Mick (The Doc) who said that a large dob and premium quality lenses is as good as visual observing gets - I tend to agree!

Please find attached a few photos of the scope which show some of the features mentioned.

[PaulB]

HI Shane,

Thank you for posting. I have some questions for please, that hope you could answer.

I am, at present looking to buy a large dob, for visual use of DSO's and the Moon and Planets.

Is it a pain having to keep moving everything to keep the object in question centred? And what was your highest power that you've used with this 12" OD300?

I also wanted to ask you please about collimation. How difficult/easy is it. And does you're OD300 need collimating when you use it?

I've been serious about buying a Skyliner Flextube 10" Auto, because of it's motorised dobsonian mount. But because I am already well known at Orion, I have owned three of there telescopes, and I am currently on my fourth. I feel that I would do better to buy ether a 10 inch or 12 inch OD from Barry rather than trust in a company that mass produces telescope's, and who's mirrors might not be up to the standard of Orion Optics. But I am sure that those mirrors are equally as good!

Does this telescope transport easily. My society and JBO host four stargazing events during the year. So it is important that I can take this telescope with me. Also I'd like to be able to go to one of my local DS observing sites in the Peak District.

Thanks again for you're review.

[Moonshane]

hi Paul

cheers for looking. I really enjoy writing reviews as others have helped me in the past and it's one of the only ways I can really give something back. I am really still a complete novice but a little bit down the road so maybe others even less experienced can read my experiences and it possibly helps. Reading your comments though I don't think you fit in that category but I'm glad to answer your queries.

Firstly though, I see you live in Cheshire as I do (I'm near Stockport). You'd be welcome to come and see my scope in the flesh as you could then gauge the size better (it's big but this wears off after a while and it's really quite manageable) and even 'have a carry' if you like.

As long as you are 'normally fit and healthy' I can wholeheartedly recommend a Dob of this size. It takes up less room than the tripod for the average refractor and is easy to move about and set up.

I can track objects very well after just a couple of uses and I would say it's very easy - initially you push or pull the wrong way but eventually you just 'know' which way to go to keep something in the eyepiece. I use the TV Radians mostly which are great and have a decent field of view of 60 degrees but I reckon even with a 40 degree plossl you'd be OK. Looking at your other gear I reckon you probably have good quality eyepieces though? I have comfortably used it on Saturn at the maximum mag. I can get with my current lenses 286x. I get the target in on the edge of one side and it floats across the view. This is one of the main reasons I got Radians - sharp edge to edge even with a f5.3 dob.

Collimation is a breeze actually. I have just posted on another thread my usual method which takes literally a couple of minutes max. I collimate every time I use it. Beware of getting too obsessed will collimation though - it's easy to become an alcocollic. Seriously though if you get it pretty close you'll still get great views. Here's the other thread http://stargazerslounge.com/astro-lounge/100694-laser-collimator.html#post1407032.

I presume that you will collimate your 200 SPX? At f4, I'd have thought that collimation is quite critical?

The OO UK optics are superb in my limited experience but I am not sure they are dramatically better than the others in our skies and seeing conditions etc. BUT the main advantage of the OO UK dobs is the base. This is made of aluminium and superbly robust and solid. Mixing water/dew and chipboard/MDF to me is asking for trouble. If you are deciding between a 10" or 12" I'd personally urge you to go for the 12". As far as I am concerned, I decided on an OO UK and only that would do and you sound the same. I do think though that the flex-tube is a great scope. I am the sort that likes to zip about from one spot to another at will (the best thing about a dob is just this) and I instinctively feel that something controlling this will reduce the enjoyment - I bet there's a hundred others who feel one way or the other though and love the auto flex-tubes!

Finally, transport. I went down to Bedford to collect mine in my wife's VW Golf. It fitted in fine with the back seat down and behind the passenger seat well forward - lots of duvets etc to prevent damage. The base in the boot at the side. You won't get many passengers in but it's an easy fit. Again you are welcome to come and see in person. As long as you have a hatchback / estate then you should have no problems.

Hope this helps and feel free to ask any further questions as needed.

I love this scope and usually choose it over the refractor at the moment as it's so easy to set up.

Cheers

Shane

[John]

Great report Shane and a very interesting scope

F/5.3 is a little "slower" than most 12" scopes and, personally, I'd prefer it if my 10" F/4.8 was a lttle slower - it does make achieving and keeping collimation that much easier.

I think you got a good buy there - the scope would have cost at least twice what you paid when new.

I used to have a 12" Meade Lightbridge. I loved what 12" could do performance-wise but the bulk was too much for me so it was not getting used as much as it deserved. the 10" Orion Optics OTA that I now have is much lighter but I note from Orions website that their 12"ers weigh less than the Meade's OTA did which must make the whole setup more manageable.

Personally I reckon you have a scope there that could fulfil a lifetime's viewing.

Thanks for posting

[Moonshane]

cheers John

I agree with what you say totally. The slightly longer FL was actually another reason I went for OO. Apparently this is the GPDX version which has optics of probably 1/6th wave and possibly better. The seller was really good though and agreed to sell to me at the worst case price as he didn't have a zygo report so assumed 1/4th wave.

Although the coatings seem good at the minute, I'll probably recoat within a couple of years to the new Hilux standard. This should further enhance things I reckon and well worth it as the primary and secondary would be around £200. I also think they (OO) produce a zygo then for free as otherwise this alone costs about 180! (not that it's really essential to know as long as it works OK). On the basis they say Hilux coatings should last 25 years, it's not much per year and the scope will then probably outlast me!

[PaulB]

Hi Shane,

You've certainly given me something to think about now. I like the idea of the OO 12" and the F5.3 model would seem to be OK. I want something that I can just through out side at a moments notice and look through. Last night was a classical example. I had to work today, so I didn't want to start imaging at 10pm. Had I had a dobsonian, then I could have spent a nice hour looking at Saturn and some of the brighter messier's visible at this time of year.

My only gripe with buying from OO is having to wait for it. Perhaps if I do choose Orion, then I'll place my order during June so that it will be ready come the return to darker skies in August.

[Moonshane]

Hi Paul

no problem at all. I am sure you know but in general terms, the larger the mirror, the longer the cool down time so mine takes at least 30-60 minutes depending on the difference between temps indoors and out.

I normally out the OTA and base outside first and then proceed to set up, alinging the finders etc and then collimating. By then it's usually at least 10-15 minutes so not longer before I can start observing. Ideally, just put it out before dusk so there's lots of time to get matters sorted.

If buying new then in my limited experience. OO are worth the wait.

good luck whatever you decide.

The offer's still there if you decide you want to have a look at mine anytime.

cheers

Shane

[PaulB]

Your not a member of Macclesfield AS are you?

[Moonshane]

hi Paul

no not at present. I am a member of a few (unrelated) groups - all entomology related - so cannot really commit to another currently as I'd not be able to 'put in the time'.

I understand they are a great group though.