Orion Optics UK 6" f11 Dobsonian Review

[Moonshane]

Hi all

This is going to be an 'emerging' thread as I have not yet used this scope having collected it from Russ near Winchester yesterday. Great to meet other SGL members (also met Kim (and Di) - Brantuk - on the way down to see Russ). Russ was kind enough to collect and store it for me as it was located close to him - cheers matey!

You may think I am slightly bananas :iamwithstupid:traveling 400 miles to collect a scope but I really didn't fancy trying to get a 5 foot tube up to Manchester via courier, especially as it came with no packaging. In the end the fuel costs of £46 plus £115 for the scope, still amounted to a bargain for a £399 new unit which had the additional bonus of a single speed GSO Crayford already fitted.

So, my first impressions of the scope:

General condition

This is to all intents and purposes a new telescope. There is a single large scratch on the tube near the rings (see below) and the end cap is somewhat damaged (see below) but otherwise it is in excellent condition. A bargain for the money.

Size and weight

Compared with my 12" dob by the same manufacturer, this is a seriously lightweight scope. The tube can be carried in one hand and it's no trouble to lift the whole thing and move it as one.

The tube has the same focal length as my other dob (1600mm) and this is one of the things that attracted me to it as my current eyepieces will have the same magnifications.

The tube easily fitted into my car through the boot and the half folded back seat (as does my 12" dob).

Build quality

OO seem to have a reputation for variable build quality in their scopes and to some extent this is unfair in my view. The general build of the scope is just the same as my 12" dob and this is of high quality, being an attractive and well designed scope and base.

The gauge of the aluminium is the same for the OTA and the base as my 12" dob. All of the fixtures are aluminium, stainless steel or brass.

All of the touching/moving surfaces run on blocks of teflon.

The scratch referred to above was caused by the projection of one of the tube ring bolts through the felt and this should have been checked at the manufacturer's to prevent this damage. The end caps are notoriously poor quality with these scopes and I am not sure why OO have not sorted this out sooner. I understand they have now done so and that the new caps and replacement parts available are of a better quality - I will be ordering one of these in due course.

The base on this scope seems to have been put together (by the purchaser) on an uneven surface and it seems a little out of kilter - this will be remedied shortly - probably by a simple dismantling and reconstruction of the base on an even/flat surface.

Design of the base

Not so much the design of the base, which is excellent but the dimensions. This is a major weakness of this scope in my view. The base is extremely tall for the footprint and for the length of the tube. It looks as though it would blow over if there was a sudden breeze and as a result, one of the first modifications I will make is to add some weight and some width to the feet/base.

The above comment may be unfair and inaccurate but I'd certainly not be happy at the minute leaving it unattended for long outside as I do with the 12".

Optics

The optics look in perfect condition with the tiny 1" secondary and a tiny primary that looks lost at the end of the long tube! The primary has a centre ring which helps with collimation of course.

Collimation of the secondary is via three small screws (I'll replaced these in due course with some kind of thumbscrew (M4) if I can find one with a small enough head!

Collimation of the primary is via three bolts which project through the end of the metal end cap which remains permanently in situ. I presume it was the previous owner and not OO that 'fixed' the collimation with locktight nuts! These have been replaced with M6 threaded rod connectors which I had in the shed, as a tool free option. Perhaps the theory of the locktight nuts was that if this was done the collimation would hold better. As it happened the collimation of both elements was well out - now sorted.

Based on the price stated by the seller as paid (£399) I assume this scope has standard (better than) 1/4PV optics - I am informed probably nearer 1/5 PV. Eventually I may possibly replace these optics with at least new coatings with HILUX (£100 approx) or even sell the optics in at the moment and buy a set of 1/10PV (£289-current optics). I'll certainly be seeing how it performs first though and am hoping for a first light tonight when I'll compare this with my 120mm achro refractor and also my 12" standard optics dob on Jupiter, the moon and some doubles; this being the purpose for which this scope was bought.

Balance

I can see this will be the major challenge of running this scope. The primary is so light that anything weighty on the viewing end will make it sag. Therefore I have two choices, use only lighter EPs (I have a Panoptic 24mm, Radian 8mm and Nagler 6-3mm zoom so this should be ok for the above purpose) or design a weighting system/buy the OO friction brake. I may well end up doing a mixture of the two.

Planned Mods

I have the following modifications planned:

Immediate/soon

• Weighting / extending the feet on the base.
  
• Sort out balancing with either a friction brake or a weight system.
  
• Flocking the interior after lining with 1.5mm foam.
  
• New end cap.
  
• Collimation 'Shane's knobs' for secondary.
  
• Dob knob.
  

Longer term after assessment

• New set of 1/10PV optics
  
• Fan (not decided if this is needed yet)
  

I have added some pics below.

[Chris H]

Have had my eye on one those for a while, looking forward to the first light report.

[Moonshane]

cheers Chris

me too! (and me too!).

[John]

Very interesting scope - thanks for posting the report and pictures. I talked to Ade Ashford about that scope shortly after he reviewed it here:

Orion Optics OD150L De-luxe

He was very impressed indeed with it.

By co-incidence, I hope to be shortly obtaining the other scope he mentions in that review - the MN61 mak-newtonian.

[Doc]

I have been contemplating one of these for ages and you have picked it up for a great price Shane, I wonder how much better the 1/10PV will be then the 1/5 PV you have, will it be worth the added expense. Make sure you keep us informed.

[Moonshane]

cheers guys - I certainly will update when I get a chance to use it.

BTW apologies to the previous owner. looking at the photos on the review, locktight nuts seem to be fitted as standard - quite bizarre.

I am just completing my second mod - I have added a bit of foam to act as a buffer where the scope 'hits' the back of the mount when vertical, and also I have some 1kg dumbbell weights and am adding one to each foot to provide some ballast.

even if maybe not required, hopefully the latter will help reduce the stress of leaving the scope outside to cool.

[Moonshane]

OK! First light.

A good start as the ISS passed over as I was checking it had not started raining about 10pm (ish).

Pre-use Modifications

Before I got started I made a couple of mods:

1) Added a small chunk of camping mat foam to the base where the scope 'hits' the base. This makes for a softer impact if it tips or when packing up etc. I didn't have anything more suitable and will make a batter job when I can find something.

2) Added some weight at the feet of the base. I had some 1KG dumbbell weights I bough for about £1 each at TESCO a while back (I knew they'd come in handy one day) and used these, bolting through the bar hole with a longer bolt and using the original feet and a large washer. It seemed to work well and as they are black they blend in, although the base looks a little like Mickey Mouse (who cares in the dark eh?).

Pics of both mods below.

General Use

As expected the balancing of this scope was an issue and it was tricky to use without the friction brake which based on a single night's viewing is likely to be essential for anyone buying this scope. The scope was constantly sagging and tipping back to vertical as eyepieces were added and removed. Even the 8mm Radian and the 24mm Panoptic has this effect.

So, my next mod will be a friction brake. I'll be making this myself and have ordered some 10mm x 30mm aluminium flat bar and 10mm teflon rod for this purpose. This will be about £10 altogether and a lot less than the £39 OO charge.

However, I managed to find (and keep in view!) a few suitable targets and compared my three scopes on the moon, Jupiter, Uranus, Neptune (seen for the first time tonight!! ), Albireo Beta Cygni and the double double Epsilon Lyra.

The night was very clear and my wife commented that there were many more stars visible than usual (Julie chilled out for a while in a lounger spotting satellites and meteors - there were actually a few Perseids knocking about still during the night). Unfortunately the seeing was apparently quite poor (did anyone else find this last night?). I tested this on Delta Cygni and could not split this star in any of my three scopes. There was a lot of dew in the air and maybe this affected things?

I was using all of the eyepieces stated below and the three scopes, 12" and 6" OO dobs and a 120mm Celestron achro. The focal length of the dobs is the same at 1600mm and the achro 1000mm. Therefore to be fair I tried on occasion to use the 6mm Nagler zoom in the achro and the 8mm Radian in the dobs. This gave magnifications of 166x in the achro and 200x in the dobs which was as close a match as I could get. I also used the 8mm in the achro from time to time giving 125x and in truth this gave the best achro viewing on the night. The dobs easily handled 200x with the 8mm and sometimes 260x+ with the 6mm end of the zoom especially on the moon. Both the newtonians were collimated prior to the observing session but after they were cooled. All scopes were outside for at least two hours before observing started.

Albireo Beta Cygni

I chose this target mainly to test the colour accuracy of the three scopes. This is a beautiful double and generally has always been slightly disappointing in the 12" as the colours generally appear a little washed out. It has always been much better in the 120. Tonight however, I found the results in the 6" to be really quite stunning. Excellent colour rendition, bright and sharp. Every bit as good as the 120 and actually just shading it.

double double Epsilon Lyra

This was a bit of a test given the poor seeing but all three scopes managed to split this pair of pairs relatively easily. The results were worst in the 12" and again about equal in the 120 and the 6". The split was a little more obviously/clear in the 6" given the increased magnification.

Jupiter

I had to wait for quite a while for Jupiter to rise above some trees at the bottom of my garden and it had therefore reached a reasonable height - I finished observing at about 3am.

This is where the 120 started to fall behind. The image probably had about the same level of detail but there was a blue halo around the disk and this was somewhat distracting. The contrast was also a level below that seen in the 6" and the lower magnification meant that details were not as obvious. The CA was helped with a William Optics filter but it was still not at the standard of the 6". The moons were actually very slightly crisper in the 120 and this is the one area on this target that the 120 was an improvement.

The 12" was good and the image large and bright but the detail was somewhat intermittent. The 6" stood apart on this subject giving much more maintained detail and with a surprising amount of contrast. These are definitely the best views I have ever had of Jupiter.

I decided to reduce the magnification on the 6" to 123x (using the 13mm Ethos - I certainly had to hand hold the tube to prevent sagging!). This yielded an even sharper and more detailed but much smaller disc, again much enhanced from the 120 with the 8mm Radian at 125x.

The result here was a resounding success for the 6".

Uranus and Neptune

There is never much detail with Uranus and tonight was no exception. However, the 6" also performed best here with a tighter disc than the other two scopes and good colour. I also managed to track down Neptune for the first time ever and the comments here are the same.

Moon

The moon has always been a favourite target of mine and it is so good to just wander around aimlessly looking at different features and not caring where you are. I took this approach with this test rather than comparing fine detail. The reason for this was that the 6" base is not as steady as the 12" or the 120 and I was effectively hand holding the tube for a lot of this session to prevent sagging.

What I can say is that again the 120 fell well behind mainly due to the accuracy of the colour in the image. Whilst the CA in this scope is well managed and easily ignore if looked at in isolation, when compared with a newtonian it is surprising how different the images are. The detail was good but to my eyes was not as sharp as in the 6" or the 12". Also, the magnifications which could be achieved with the 120 were not even close to the newtonians.

It was very difficult to split the 6" and 12" in terms of the actual detail viewable. They both showed excellent images and even though the seeing was not good, it was possible to use the Nagler zoom down to around 4mm (400x) before the image really started to break down. Again I would say the image was more stable for longer periods in the 6"

I ended the night with a long look at the moon through the 6" using the 24mm Panoptic and in the 12" using the 35mm Panoptic. Both scopes and eyepieces framed the whole moon beautifully and at the lower magnification the sharpness and detail was really quite stunning. I found that I much preferred the unfiltered view as although this tends to sock you in the eye initially, once your pupil has contracted to a pinprick (!) it's really nice to see the whole effect in a more natural way.

I have no doubt that the performance of the 6" lives up to expectations. This is the basic optics model of the scope and I assume that with better figure and HILUX coatings this would enhance the views even further. With blackened secondary edges and flocking (either in full or just on the wall opposite the focuser etc) I think my own unit will have even better contrast and if I decide to go for better optics in due course this will almost certainly be worthwhile.

I'll be happier once I can get the balancing issues sorted and mount my Rigel as all of this will mean that more detail and prolonged comparisons can be made. I'll also seek the confirmation of others that what I am seeing is what they see too. Despite me thinking I'd never sell my first scope, it does look as though that there will be a 120 achro, mount and diagonal on the for sale boards quite soon

I'll keep updating this thread as I make further comparisons and hopefully after a night of excellent seeing.

Cheers

Shane

[Moonshane]

Well, I have just done mod 3.

As mentioned the end cap was somewhat cracked and split around the rim. I was going to buy another and then though well, why not just use some back insulation tape?

I did and it's now perfectly serviceable. I did the same to my 12" end caps to as a preventative measure and hopefully they'll last a lot longer now.

Others have confirmed that the seeing was as poor for them last night too so cannot now wait to get another go on a better night - no chance tonight - getting the black looks and work tomorrow.

[russ]

Brilliant Shane. You bagged yourself a bargain there. I was stunned how good that scope was. And that was with the collimation off. Not sure how much you'll gain with the 1/10th PV optics over the current ones, as they are already extremely good. Contrast in that scope is truly amazing and yes, Albireo was about the best i've seen it.

And what a cracker it will be with all those mods completed. You'll have to let me know what you use for 'Shane's secondary Knobs', i can then use the same for Harry's OO 150.

[Moonshane]

I used this scope again last night determined to get another chance to look at Jupiter seeing as everyone has been commenting on how good the seeing has been recently in patches at least.

The views of Jupiter were once again improved and I am beginning to see what this scope is all about.

The seeing was quite poor again generally last night for me and this is made worse specifically from my location as I am observing right over rooftops to see the planet. I did not use any filters as I preferred the unfiltered view after trying the ND filter.

As a result of this, whilst the image of Jupiter was acceptable with the 8mm Radian at 200x, I decided to drop down to my 13mm Ethos to see what I could see at a lower mag (123x). I am so glad I did as the detail seen with this eyepiece was nothing short of spectacular in the moments of excellent seeing that ensued. I was delighted that the GRS was in full view (believe it or not I have never seen this before), really shining out in glorious pink and so obvious.

Above this was a dark and light 'eyebrow' and I agree with others that it appears the SEB may be reforming - it at least looks that way.

I was seeing paler patches of detail within the NEB and banding and darker colouration was really outstanding at the poles.

The image was occasionally 'photographic quality' and I think based on this session (and despite my recent decision to reduce my eyepiece collection to a minimum to prevent me constantly changing and not observing) I think my next eyepiece will be a 10mm Radian and not an 8mm Ethos. This way I can measure the most used eyepiece of the two and eventually replace that on with an Ethos.

The above detail was seen with me effectively hand holding the scope as the weight of this eyepiece was impossible to balance without the friction brake which I will hopefully be able to make for the next observing session.

I eventually dragged myself away from the scope at 1.20am as it's a working day today - bleary eyes again!

[NGC 1502]

Hi Shane, great review, thanks !

I bet O.O. will get some orders out of this,

you should get some advertising money

from them

I too saw a pinkish GRS, first time I've seen

any colour here, confirmed by my wife,

with no prompting from me.

Cheers, Ed.

[John]

...I too saw a pinkish GRS, first time I've seen any colour here...

The GRS definately looks more akin to it's name this year - in previous years "Pale Grey Spot" would have been more apt !.

[Rob]

Agreed.. jupiters colours this year are fantastic. nice scope, nearly nabbed it myself

Rob

[Moonshane]

ha ha glad you didn't as if you had, we'd have both lost in a way (one way or t'other)

I agree this is a great scope and worth trying even with standard optics like mine. truly the views were awesome even at relatively low magnification.

[Moonshane]

OK, knowing that OO usually put stickers and inscriptions on their mirrors, curiosity got the better of me this morning. So I took the primary out to see what it would reveal. I was delighted when I read the very satisfactory markings which read:

"HILUX" and "1/6"

I had been assuming that these were standard 1/4 or better optics as this is what the advert suggested but this better grade and the HILUX coatings explain why both Russ and I felt the performance was excellent. What a result! Effectively, I bought the scope for the price of a HILUX recoat

On this basis I am seriously reconsidering any need to refigure/recoat the optics or buying a 1/10PV set.

[johninderby]

The deluxe version comes with the 1/6 PV optics and Hilux. Maybe the seller was a little bit confused and called it standard as it was the regular delux without any optics upgrade.

BTW as OO's ratings are given as better than this means you've probably got about 1/7 PV.

Even more of a steal you jammy so and so :D

John

[Moonshane]

you may be right John

I was surprised as he also said he paid £399. Maybe it was a hand me down or something and he assumed it was the standard one. Either way I don't really mind and I'm delighted I was 'brave' and went for it, despite the distance to collect!

Looking forward to more Jupiter views - cannot take my eyes off it at the minute.

[kris h]

Great review Shane congrats on your new scope

clear skies