Which size of Dobsonian

[shanmac]

Hey guys, I’m in the hunt for a Dobsonian to accompany my 127 mak. I’m thinking an 8, 10 or 12 inch but can’t decide if the 12 is worth the extra cash over the 8 or the 10. I live in the countryside so light pollution isn’t really a big issue. I know bigger is better so it may be a no brainier. Any thoughts?

[michael.h.f.wilkinson]

Check out the weights of these scopes, and how readily you can set them up. Then go for the biggest you can handle readily (and afford, of course)

[johninderby]

The 12” is a lot bigger and heavier than the 10” or the 8” and harder to move around but yes it will deliver a big increase in performance over the 10”. If the price and size aren’t a problem it would be the one to go for.

 

[PaulM]

I have two skywatcher dobs, an 8" (200p) and 12" (300p) which is a flexi goto 

The 12" flexi goto is on the limits of a single person being able to move it around within small distances taking the tube off the base

If you can live with a 12" then thats the one to get - pic shows size comparison between the two, the 300p is on a dolly making it look taller than it actually is

[Seanelly]

I've owned a 4 1/2" and then a 6" dob in the past, wanting bigger almost immediately. I've now owned a well-used 10" dob for 19 years, and it has cured my urge to upsize, as it is the limit for me to load, haul and set up in reasonable comfort around the backyard, roadsides and countrysides.  

[Moonshane]

If you can get a 12" f4 I'd recommend that but a 10" would keep you going for years. Here's my 12" f4

 

[Alan White]

I have recently bought an OOUK 10" dob and find this as big as I want to handle.
I am average height and larger build so moving things is not a problem for me at all,
however, the challenge is the bulk, even when split into two parts, it is a big tube.

Aperture fever is fine, but soon cured if you over do the aperture in my opinion.
Great views bigger, but none if you don't use it because it is too much hassle.

[NGC 1502]

 

Good advice above.  Always a tough call to give advice.

A 12” or larger could work if you can store it close to where it will be used, and wheeled out of a shed or similar.

Different situation if you need to carry it around or transport it to a viewing site - can you lift it, will it fit across the back seat of your car ?  Of course you could have a flexi-dob or truss tube to make it more transportable.

For myself my 10” solid tube gets the job done, fits the car, no assembly, no hassle.

Of course if you belong to a club or attend star parties then you will find some are ok with very large scopes. It’s a case of finding out what suits you best, not anyone else.

Ed.

[shanmac]

Thanks for that guys. I think I have now removed the 8" from the equation. I have plenty of room for storage, and have no worries about it being too heavy as I wouldnt have to move it too far from where it will be stored. Budget is a bit of a concern but not strict. I think my main concern is the price difference between the 10" and the 12".

Is the 12" worth the extra £300+ ?

[Ricochet]

When I bought mine I went with an 8", because Bresser didn't offer a 10" at the time. Having used it for a few years I'm often glad that i didn't get the 10" in terms of weight as the 8" is at the limit to be carried as a single unit. If you go for the 10" or larger I think it really should be split into two parts, even for the shortest of moves or you risk damaging your back. Remember also, that when cold (i.e. after hours of observing) your muscles will be more prone to damage.

[NGC 1502]

 

39 minutes ago, Ricochet said:

When I bought mine I went with an 8", because Bresser didn't offer a 10" at the time. Having used it for a few years I'm often glad that i didn't get the 10" in terms of weight as the 8" is at the limit to be carried as a single unit. If you go for the 10" or larger I think it really should be split into two parts, even for the shortest of moves or you risk damaging your back. Remember also, that when cold (i.e. after hours of observing) your muscles will be more prone to damage.

 

An 8” could easily be a lifetime scope. It’s a matter of finding out what suits us, not anyone else, and there’s only one way to find that out, by using something. If you belong to a local club that has scopes to borrow, that’s a great way to find out, and the cost of club membership could save you loads of cash.

Ed.

 

 

[Astro-Geek]

I wish this thread had been around when I bought my first Dob a few months ago...  ?

The replies highlight moveability, which I underestimated.

For anyone else contemplating 8, 10 or 12, age and strength (and back health !) are vital factors.

I initially went for a 10" GSO with a solid tube (because the flex is actually heavier, and the base is identical), because I had no need to transport by car. I'm lucky enough to live in a very rural area 10 miles from the nearest city and with no street lights.

I misjudged the movement in and out of the house though.  My conservatory accesses the patio via a single width door and three steps, and it's quite a struggle for me (67 years old), to lift it in and out, even in the two main parts.  If it was like my previous house, with a wide patio door and level surface, it would have been a breeze, especially as I tried mounting it on a triangular furniture dolly with large ball bearing wheels.

I therefore subsequently bought a 200pds and EQ mount, which is much easier to get through the door and setup, and a 200 dob would be even easier.

If anyone reading this is old and (slightly !) decrepit like me, try to handle a 10" before you buy, rather than judging by photos and dimensions.  The weight is not the problem, it's the bulk and awkwardness, especially the dismounted OTA, which is like struggling with slippery slim Dalek, with a fragile glass bum !!

[NGC 1502]

7 hours ago, shanmac said:

Is the 12" worth the extra £300+ ?

 

That’s a really tough question. If you have the money to spare, then yes, as long as your certain you’re up for the extra weight and size.  There’s always the second hand option of course......

Ed.

[Alan White]

43 minutes ago, Astro-Geek said:

I misjudged the movement in and out of the house though. 
My conservatory accesses the patio via a single width door and three steps, and it's quite a struggle for me (67 years old), to lift it in and out,
even in the two main parts. 
If it was like my previous house, with a wide patio door and level surface, it would have been a breeze,
especially as I tried mounting it on a triangular furniture dolly with large ball bearing wheels.

This is very much an issue, its not the lift, its not the putting down where most manual handling injuries occur,
it is during the environment that you carry through that causes the problem.If you have done carrying training its the E of t.i.l.e.
You can tell I work in H&S now, sorry.

[johninderby]

Fitting carrying handles makes carrying the tube so much easier. One big main carry handle and a small one at the top. 

 

[NGC 1502]

 

The wheels on the Dob bases in the previous post are exactly what I was referring to earlier.  If you can store the scope close to where it’s used, makes a larger & heavier scope feasible.

Ed.

[shanmac]

Ok, thanks folks for your sound advice.

So, i've just purchased a 10" Bresser Messier Dob S/H at decent money, i'll let you know how I get on ?