Dob 12’’ Explore Scientific, SW, or Meade ??

[JoseLuis]

Good evening everyone.

I’m planning on picking up a 12’’ Dob and I have to decide among the Meade Lightbridge 12’’, the Sky-Watcher flex tube 12’’, or the Explore Scientific Ultra Light 12’’.

I have read here (http://stargazerslounge.com/topic/163412-lightbridge-or-flex-tube-dob/) comparing the Meade with the SW, and it seems the winner is the SW.  I have also read here that some people already have the ES, so they must know its performance under the sky, compared with the other two.

I’m especially interested in deep sky galaxies, therefore, the most important points for me are the optical quality and the portability to transport the telescope to dark sky sites. The best portability is for the ES but I don’t know if I have to pay for it some loose in optical quality with respect to the SW or Meade.

Also are there any build quality issues or any problems right out of the box with any of them?

Which one would you recommend me?

Thanks for your advice.

Jose Luis

[Tinker1947]

If you were after a GoTo Dob i would recommend the SkyWatcher 300P, the GoTo is really accurate and tracking after 45 minutes it still had a DSO in its FOV ( Nagler 17mm) i can say the optics are good but better than your other  2 choices a can't say as i haven't used them....Good Luck with what ever you settle for.....

[John]

Hi Jose and welcome to the forum !

Here is a thread from the one member of the forum who has an ES 12" dob:

http://stargazerslounge.com/topic/214494-explore-scientific-305mm-12-ultra-light-dobsonian/?hl=+es%20+dobsonian

There may be others but Russell is the only one I know of.

I've owned a Meade Lightbridge and found it OK but it did need a fair bit of improvement out of the box, eg: replacement primary collimation splrings, a better finder and some counterweighting at the back end when I used heavy eyepieces. The primary mirror coatings seemed not to be wearing too well either.

I've owned the Skywatcher 8" and 10" dobs and found those good scopes. I've used a few of the Skywatcher 12" Flextubes and those seemed pretty good to (apart from the unfortunate name !).

I think all dobs need some fine tuning out of the box though, in all honesty.

In terms of optical quality I don't think there will be much between them. They are all around 1/4 - 1/5th wave PV I believe with the odd one that is better and occasionally one that is worse.

[Michael11]

Hi Jose,

I would not recommend a Lightbridge. The mirror cell is simply awful and I've already seen a 12" Lightbridge mirror full with corrosion.

A motorised Skywatcher would be nicer - much better mirror cell, faster setup (telescopic truss) and the GoTo option of course which works quite well. Also Synta mirror coatings aren't known to have issues.

Regarding the Explore Scientific - there is a thread about it somewere around here.

[JoseLuis]

Thank you very much for your answers,

Then, after reading your answers, I would choose the SW or the ES, and the ES is much better in transportability than the SW, so the Explore Scientific seems to me the best option for the use I am going to give it.

I've read the thread John recommends about the ES and it seems that Rusell was not very lucky with his telescope, since he had to do some fixing. The thread finishs in May when Rusell had not tested the telescope in a clear night without Moon. John do you know what happened after that? I'm specially interested in the deep sky objects performance?

What do you think about choosing the Explore Scientific telescope?

Thanks.

Jose Luis

[Michael11]

Regarding portability - the Skywatcher is indeed larger and takes a single car seat at the back. However it is faster and eaiser to setup. But if you want to keep all of your seats free - you are probably right to go with the ES.

[JoseLuis]

Thank you for your answer Michael,

Could you upload a picture of the SW in a single cat seat to make me an idea if I would be able to do the same in my car? How many centimeters the packed telescope make in each of the three sides?

Jose Luis

[John]

Thank you for your answer Michael,

Could you upload a picture of the SW in a single cat seat to make me an idea if I would be able to do the same in my car? How many centimeters the packed telescope make in each of the three sides?

Jose Luis

Jose,

To save Michael doing that, have a look at this link. The dimensions of the Skywatcher 12" Flextube are given and there are some photos at the bottom of the page of it being loaded into a car and on the back seat of one. I hope that helps:

http://www.opticstar.com/Run/Astronomy/Astro-Telescopes-Skywatcher.asp?p=0_10_1_3_280

[Charic]

I personally wouldn't have a flex-tube. I just don't like the idea of collapsing the focal length every time I wanted to store the telescope, having to check collimation EVERYTIME I extend the OTA,  and I feel that at some time in the future wear & tear might be an issue?

Also my street light pollution,  would be an issue for me on an open OTA (Optical Tube Assembly )!

I would also choose  the 12" as you so desire in preference to a 10" (considering my present scope f/6 ) The focal ratio on a 10" would be too fast for my needs.

Lastly, I would only wan't a bigger aperture to increase the image scale slightly?

My  8" fits across the back seat with a few inches to spare. Ford Focus, a 10 / 12" should still fit the same sized car.

[scarp15]

Thank you for your answer Michael,

Could you upload a picture of the SW in a single cat seat to make me an idea if I would be able to do the same in my car? How many centimeters the packed telescope make in each of the three sides?

Jose Luis

Here are some pictures of my former 300p Flextube. I transported it across the back seat of my Skoda Fabia hatchback, the base in the boot. Final picture on location. It would have also been possible to transport it upright in the front passenger seat with seat slightly reclined and supported by seat belt had I wished.

[Digger1895]

Could you show me a picture of it in a Mondeo?

[John]

Could you show me a picture of it in a Mondeo?

We'll do a calendar for 2015 - the Skywatcher Flextube 12" in a variety of popular vehicles each month

[JoseLuis]

Thank you very much for your answers, links, and pictures. Even it is a big telescope, it fits pretty well in a car... but I don´t know where to sit my wife and children in the case they want to came with me... I´ll have to choose between family or Dobson... I´ll think about. Or maybe the Explore Scientific will allow to combine both.

I am sure that it is worthy to solve the telescope transportation issues, once you are watching through the telescope in a dark starry sky.

Thank you again for yor help.

[Charic]

I know you mean well, but it has to be the Dobsonian! The Wife & Children's interest will wane far quicker than yours, and on  colder Winters nights, even in Spain,  they'll want to be engrossed in the their game consoles, and the Mrs snug in a Duvet with the nightcap coffee.

You'll do well with a bigger Dobsonian. Not sure how many folk have separated yet due to the size of a mans telescope? You may be the first!

[scarp15]

Yes as Charic has pointed out, large non truss dobsonian's are not really compatible with families, though the 12" flextube was fine for taking one passenger.  For family camping trips I take my binoculars and monopod. Since I replaced the 12" flextube for a 14" solid tube the car space has altered again. But as said stargazing is my thing and not really my Wife and daughters.

[CarolandDom]

We have fairly recently acquired a SW 300 elective. What a great piece of kit. It's a little heavy but definitely portable

[JoseLuis]

Well, I love stargazing, but I love my family too so I guess I´ll have to split the nights... some with the telescope and some with them. But first I´ll try to find more information about the Explore Scientific 12'' to see if it we can fit all together in the car without loosing stargazing capabilities with respect to the SW 12'' flextube.

Scarp it is amazing how could you fit the 14'' solid tube dob in your car, I understand your family stay at home while you travel with that telescope. I am sure it is worthy under a dark sky!!

By the way John when you have ready those calendars, I´d like to buy one.

[John]

By the way John when you have ready those calendars, I´d like to buy one.

OK - I'll get on to it !

[Tinker1947]

OK - I'll get on to it !

I thought it would be cars  not self'is....."OK - I'll get on to it "....

[scarp15]

Well, I love stargazing, but I love my family too so I guess I´ll have to split the nights... some with the telescope and some with them. But first I´ll try to find more information about the Explore Scientific 12'' to see if it we can fit all together in the car without loosing stargazing capabilities with respect to the SW 12'' flextube.

Scarp it is amazing how could you fit the 14'' solid tube dob in your car, I understand your family stay at home while you travel with that telescope. I am sure it is worthy under a dark sky!!

By the way John when you have ready those calendars, I´d like to buy one.

OK - I'll get on to it !

Yep more cars n' scopes please sounds like a cracking calendar in the make. The profile of 14" scope appears deceptive, whilst not exactly light it is, at least this version which is constructed in aluminum, quite light and so fairly easy to maneuver. The mirror is lighter to compared to alternatives.  When I first joined this forum I asked a similar question (in fact that was the reason I joined) concerning how portable a 12" dobsonian would be in relatively small cars. Some responses were on the lines of 'well if the scope does not fit, then change the car' at the time I thought this to be a little well obsessive. However I am now of the same (obsessed) mind set, when the car does need to be replaced, we will be looking at the Skoda Fabia Estate (for the calendar of course!).

As for the family, they are welcome to stay in and indulge in their weekend TV or DVD's whilst I gratefully get the opportunity to go out.   

[russ.will]

Just my 2p - Optically, I don't think there is a discernible difference in it between the ES and the SW. I spent a long time convinced something wasn't right with the mirrors of my 300p, but then on a couple of nights before it left my ownership I had some absolutely incredible views of Jupiter, so it was more likely that I just hadn't lucked into many nights of good seeing with it. I've had similar views with the ES, so there's nothing in it.

The reasons it went were multiple. Compared to the ES, it is a collection of very heavy and large lumps of wood and metal. The FlexTube does just bring the OTA down to an acceptable (for me) length, but the base is still over 2ft in diametre and just as tall. We could travel as a family of three (Ford Kuga) with scope, or luggage, but not both.

Mechanically, I found no issues with collimation. Indeed, if the 300p was only being transferred collapsed between house and garden, I frequently found no need to re-collimate. The GOTO on the other hand was horrific as the slip tension on the clutches (that allowed the push-to facility) seemed to be highly variable depending on temperature. Sometimes, it was very good. Sometimes, it wouldn't even get the subject in the middle of a 24mm EP on the first slew after three star alignment. Dr. robin had a very good thread on his attempts to get on top of the SW Dob GOTO, but I clearly lacked his commitment.

In the end, I was using mine with a setting circle and Wixey for finding things and the GOTO was really just providing tracking, which it did very well.

The ES is a lot lighter, smaller and breaks down into much more manageable and transportable chunks. Collimation after assembly is mandatory, but numbering the poles so they always go in the same position minimizes this. It should be said that the fact you can collimate the mirror from the front makes this task so easy as to laughable, rather than feared. I even tweak using defocused stars as the night goes along from the position in which I am seated.

Build quality is a bit more suspect. I'd like to see threaded steel or brass inserts where steel screws are used to remove the possibility of threads stripping - keep them well greased to guard against this.

You also need to check the mirror cell actually floats, as star shapes can be a bit odd if it's all done up tight like mine was when it arrived.

The horizontal focuser position is just plain stupid - You're on your knees for anything below 45deg. The R&P focuser is really nice for a standard fit item - very smooth and precise.

Nudging is a bit sticky, particularly in the Az plane, but it's a lot better than the SW was, albeit that kept a subject centered once you got it there.

Some sage type noted that all Dobs are an on-going project and neither of these scopes disproves that! ES have been rolling out various upgrades to deal with faults that early adopters like myself suffered and they have been sending them out free to existing owners. If I were to buy either again, it would probably be the ES, simply because the views are as good and it travels with me far more frequently than the FexTube could. Indeed, I sometimes wonder if I could have got away with the 16". Ho hum.

Russell

[denis0007dl]

I had 12" GSO dob and sold it because it was too bulky. I would go with SW flex tube!

[JoseLuis]

Hi all,

I´ve been out for some time. Russell thank you very much for the detailed information. I will finally go for the ES, I think it is the best option for me. I will tell you how was everything when I have it.

Thank you all for your advice!!!

Jose Luis