12 or 14 inch Dob?

[Mr Moff]

Good morning, I'm thinking of getting a bigger Dob at Christmas and was wondering if the Skywatcher 12 inch and 14 inch flex tubes have a low enough eyepiece height for me to use them in the seated position?

I love using my 200p while sitting so I'm hoping to do the same with my next purchase.

[Mike73]

You can stay seated with the 12" no problem, I cant comment on the EP height of the 14" as I've never used one.

I had a tough time deciding between the 12"/14" SW's but in the end went for the 12" and I'm glad I did as for me its size and weight was about my limit.

[swamp thing]

That would depend on what you were looking at really.

large Dobs have a huge range of eyepiece heights. You may be standing up when observing the zenith and kneeling on the ground when near he horizon.

A good adjustable stool/chair is the answer. Personally I'd get the scope then worry about the seating arrangements

[Joguj]

My thoughts exactly. My 12" Orion can't be any different and anything above 30deg Alt would be tricky to be seated at, with non adjustable seats that is. I have used a tall bar stool with lots of cushions on once but it's a bit of a faff!

[acey]

With my 12" flextube I can view anything from the horizon to the zenith while seated. But on upgrading from my 8" I needed to use a different stool, rather than the chair I had previously been using. With the 12" I use a wooden 3-legged spindle stool (sometimes called a draughtsman's chair). The seat is on a wooden screwed spindle and you just twirl to raise or lower it - it gtives exactly the right height range for the scope. I got mine from Habitat about 20 years ago, IKEA used to sell them too. Only place I see them on sale now is in U.S. with exorbitant postage costs. A pity as to my mind these make perfect observing chairs. It fits easily in the car with my other gear and works fine on the grassy ground at my dark site.

[Mr Moff]

Thanks for the replies.

The chair I use at the moment is an office reclining chair that does have adjustable height, but it doesn't adjust that much. Maybe 8 inches or so.

Just gotta think about whether to go 12 inch or 14 now.

Plenty of time left to decide though.

[scarp15]

I think that there is only a 7cm difference between the tube lengths, as the 350p is at F4.5 where as the 300p is around F5. However I do not know if the base of the 350p will be a bit taller though adding another cm or two.

As has been mentioned though, certainly no problems seated in most positions with a good adjustable observers chair whilst using the 300P.

[FarSide]

Aperture is king, everytime.

[alan potts]

Come on it's got to be 14 inch. If you get the 12 inch you will for ever be wondering if the extra 2 inches maks a difference. With the 14 you can make a mask with holes in like Moonshane and use it as differnent size scopes with no mirror in the light path.

Alan.

[estwing]

going from 8" to 12 or 14 will be an eye-opener,i have to use a step with mine alot because i leave it on the buggy

[Mr Moff]

It's got to be the 14 then. Just gotta save a bit more now.

[Mike73]

Just to throw a curve ball in....

If you want something a little more portable then you could get a 12" Sumerian Canopus for around the same money as a 14" SW.

[swamp thing]

Just a little something to muse over:

A 12" scope is what I would call on the cusp of large scopes. It's around this size where scopes start to become big and heavy.

For this reason IMO it's very wise to have a second, smaller scope for those times when lugging a big one out isn't that attractive (nights near full moon, limited time sessions etc).

Whilst a 12" is on the cusp and a second scope is wise. A 14" is a large scope and having a second smaller one is vital.

Having owned large scopes myself I find a second scope of real benefit. Trust me you don't wanna be hauling a big lump out every time you observe. I would deffinitily keep your 8" scope as a second scope.

Of coarse if the new scope is to be housed in an observatory this is of little concern and a second scope is not needed.

Ps seeing one of these lumps in the flesh is pretty Importent before ordering, remember though, they never look as big in the showroom as they do when in your front room.

Good luck with your decision.

[Bart]

Just a little something to muse over:

A 12" scope is what I would call on the cusp of large scopes. It's around this size where scopes start to become big and heavy.

For this reason IMO it's very wise to have a second, smaller scope for those times when lugging a big one out isn't that attractive (nights near full moon, limited time sessions etc).

Whilst a 12" is on the cusp and a second scope is wise. A 14" is a large scope and having a second smaller one is vital.

Having owned large scopes myself I find a second scope of real benefit. Trust me you don't wanna be hauling a big lump out every time you observe. I would deffinitily keep your 8" scope as a second scope.

Of coarse if the new scope is to be housed in an observatory this is of little concern and a second scope is not needed.

Ps seeing one of these lumps in the flesh is pretty Importent before ordering, remember though, they never look as big in the showroom as they do when in your front room.

Good luck with your decision.

I agree wholeheartedly with you Steve, with a big'un, its an excellent idea to have a smaller one to 'whip' out. Otherwise you will miss out on some less than perfect nights where you won't have the cool down time/inclination to bring out the big one.

Saying that, always go for the biggest you can....

Keep in mind the F ratio between the scopes. Don't know the particulars here, but if one is F5 and one is F4 or F4.5, it will have a bearing on the performance of the eyepieces you decide on. Apart from the bigger price tag of the 14", if its F4.5, then you most likely have to spend some extra bob on the EPs

[estwing]

when i "up-the-app" the 12"'s gotta go...but the 63's going nowhere

[Naemeth]

Also remember it's useless getting a huge scope you aren't going to be able to take out to use. Might be an idea to see how easily you can lift the 12" and the 14", as a great saying on here is that "the best telescope you can buy is the one you will use the most", if a 14" or 16" is going to be indoors a lot, whereas a 12" would be out every (or nearly every) clear night, then the 12" makes more sense. For your wallet, a 12" F/5 will be far cheaper both in terms of the actual scope but also the eyepieces.... (having said that though, you have a range that would work fairly well at F/4.5, but you would still see a benefit in an entire set of Ethoi or Naglers )

HTH.

[johninderby]

As previously mentioned a big scope is no use if it's a pain to haul it outside and it takes a while to set up. If you've got a shed that you can store it in fully setup and ready to just roll outside that's another matter.

I had a 12"Skywatcher which I was very happy with but wanted more aperture and so I sold it and bought a 16" Lightbridge. The 16" was big and heavy and didn't get that much use.

I suppose what I wanted was more aperture but similar in weight and portability to the 12".After doing a lot of research I decided on the Orion Optics OD350 14" dob (mine has a .990 Strehl mirror). Every bit as good as the 16" LB on DSOs and much better on Lunar/planetary and cools down much more quickly. When stored away it takes up less floorspace than an 8" Skywatcher. Takes about 60 seconds to move outside and set up.

John

[vlebo]

As previously mentioned a big scope is no use if it's a pain to haul it outside and it takes a while to set up. If you've got a shed that you can store it in fully setup and ready to just roll outside that's another matter.

I had a 12"Skywatcher which I was very happy with but wanted more aperture and so I sold it and bought a 16" Lightbridge. The 16" was big and heavy and didn't get that much use.

I suppose what I wanted was more aperture but similar in weight and portability to the 12".After doing a lot of research I decided on the Orion Optics OD350 14" dob (mine has a .990 Strehl mirror). Every bit as good as the 16" LB on DSOs and much better on Lunar/planetary and cools down much more quickly. When stored away it takes up less floorspace than an 8" Skywatcher. Takes about 60 seconds to move outside and set up.

John

That is exactly the rerason I have been looking at Orion Optics dobs. Yes they are a lot more expensive but come with better optics and can be built to your spec. The 12" VX tube , for example , weighs 14 kg and is 1.16 metres long making it ideal for storage and transportation. Fully specked up it comes in at approx £1800 but you will have a scope that is much easier to use and of a higher optical quality than any mass produced dob.

[Moonshane]

don't forget that you can buy a OOUK dob used for about £500-600 depending on condition etc. a far better prospect if you can wait. or buy just a used tube (maybe £300-400) and make a dob base. I did this with my 16". OOUK mirrors are usually thinner than other brands and this is a major factor in cooling and weight.

I have the above 16" but have sold my 6" suitcase dob to fund the purchase of a grab and go 12" f4 tube which I will (eventually) make into a truss system that can be packed away small when traveling.

if you can handle the size and weight of a 14" or even a 16" this is a good thing but I agree that a smaller scope is a good idea for those short sessions when lugging out the big gun can seem like a chore.

[Chris33benoit]

I know this topic is older but gotta say I just bought a 12 inch Meade Lightbridge Dob and I love it.  So easy to use and it is powerful.  Came with a few accessories and the delivery time was amazing.  Happy stargazing!

[Bart]

Good luck with the 12". It'll show you loada

[Beulah]

No complaints about the 12". I went from 8" to 12" and the difference is astonishing, in terms of light grasp. Went up to 16" and more amazing still. The possibility of acquiring even larger apertures is well out of my budget.

Out of the 3, I found the 12" almost the sweet spot for relative portability, and good light grasp.

However, with even more portable, lighter scopes with generous aperture being available now, it is worth considering a portable, fast, focal length scope where the eyepiece height is comfortable without having to stand on tiptoes or use a stepladder.

....a 20", F/3.0 dob, please!