Dobsonian decision debacle

[simonharrison]

Hi all

Newbie here. Not a newbie to astronomy though - I began many years ago aged 15 with a 4.5" reflector on an EQ mount, bought from BC&F (whatever happened to them ?) then at university my wife and I were lucky enough to occasionally use the telescopes at ULO (Joynson 6" refractor, Radcliffe 24" and 10" Meade LX200's). But since year 2000 - nothing.

I've recently moved to deepest darkest rural Sussex, well, maybe not so dark, no streetlights but still Bortle class 4...Anyhow, here I am, the new house has a large double-doored shed with flat patio and good sky visibility. So I'm after a telescope for mainly visual. I'm not constrained by portability or size, and I'm not one to muck about so I'm after something fairly large like a 14" or 16" Dobsonian. But I have very quickly realised there are nearly no new telescopes in stock anywhere on the planet!

Companies have told me Skywatcher dobs may be coming towards June/July. I'm not sure I'm that patient. It's also galling to see the massive price increases which may be here to stay.

So I'm basically severely limited for choice and mainly to classifieds or eBay. But, with some searching I do have two firm options:

- Skywatcher 16" 400p with GOTO - £2600

- Meade LightBridge 16" (all manual) - £1750

Both brand new, although the Skywatcher is a customer return (too big apparently...

The dilemma is I would rather like to have tracking. GOTO would be useful, but mainly the tracking. Partly to keep things in view, eg for when the kids come to look at a planet, or I head inside for a cuppa. Partly to do some webcam photography of the planets. The question is whether tracking (and goto) is worth all that extra outlay? Appreciate it’s kind of personal a choice, but maybe to help me decide, a couple of questions:

1. Does anyone have any opinions about LightBridge vs Skywatcher dobsonians, in general? I’ve read lots of opinions about the Skywatcher, but there’s not much about the Meade.

2. My use will be mainly visual but I’d like to stick my Canon DSLR or buy a CCD to do some planetary imaging using frame stacking, just for fun. Will this be entirely a pain with planet racing across the FOV at high mags? Is it even easy to nudge a huge 16” dobsonian to keep a planet in view at high mag?

 

Thanks.

Simon

 

[KP82]

For high mag views of the planets, tracking or at least some forms of manual slow-motion control is a must for me personally. I'm not a fan with nudging my dob (often overshoot) and often use my refractors on a tracking EQ mount for planets despite slightly less resolution. I'd imagine for a 16" dob the nudging will be even more difficult.

[John]

The problem with a big dob, even if driven, is that shorter people need a ladder, which can be tricky in the dark. They tend to hang on to the scope, which does not work out well !

My society has an 18 inch newtonian but that is hardly used for outreach for similar reasons.

The 12 inch SCT is much easier to share with people, the eyepiece being in a convenient position.

 

[lenscap]

Do you have diy skills?

You could build an equatorial tracking platform for a manual dob. Lots of guides online.

Or you could build an Onstep Goto system. Examples here, including a system for a 22" dob.   https://onstep.groups.io/g/main/wiki/4414  

Either option would cost much less than the premium of £850 for the Skywatcher Goto, versus the manual Meade.

Edited February 17, 2021 by lenscap
typo

[SMF]

Hi,

Had a very similar experience, borrowed scopes at college, got hooked, purchased 4” reflector on an eq on leaving and used that for the last 3 ½ decades.

Kids left, house/wallet allowed so treated myself, started with a 200p on eq5 a few years back and fitted it with an RA motor drive.

Wanted more so last year started looking at the same scopes as you. Particularly the 14” and 16” Skywatcher dobs with goto.

I was nervous about dobs.  I love and understand eq mounts.

Not being able to source new I ended up buying a second hand VX12L dob from another member on this forum.

Frankly it’s awesome, the extra aperture is impressive and brings back memories of my college years. The secondhand experience proved very positive.

However I absolutely loath nudging the thing. Especially at high mag. Compared to the relaxed viewing experience of an eq I’ve come to accept it’s not for me.

If Skywatcher hadn’t increased the prices so dramatically I was about to order and EQ6 size mount to try the VX12L on.

As it is, the size of increase has annoyed me on principal and I don’t get the maths. To me, the reasons they give don’t add up to such  a huge increase. I’m now planning on building an eq platform for the dob. Considering how bad the weather has been this year for the SE at least it’ll be something useful to do within the hobby on cloudy nights. In mad moments I’m even contemplating making a manual eq for it. Luckily I have access to a full machine/welding shop and an M&E background.

I find I still use the 200p particularly for planets/lunar and use the VX12L more for dso (even though it excels on planetary views).

I dapple in very rudimentary AP using an old DSLR with both scopes and find it very satisfying even if the results are basic. The eq is much better at this and a lot of fun for very little outlay, just don’t expect to compete with others on this forum let alone Hubble.

For me, RA tracking is a must for visual. Either by simple slow motion manual or motor drive.

Keep an eye on the second hand market, I found it very worthwhile for the VX12L, a 150 SkyMax and in putting together a set of Pentax eyepieces. It also suited my impetuous nature not wanting to wait up to 12 weeks once the idea is in my head.

I found half the fun was in tracking the equipment down in the classifieds at justifiable prices.

Edited February 17, 2021 by SMF
Spelling error

[scarp15]

Hi and welcome to SGL.

As John mentions, 12" is a good and manageable size, yet going bigger, well why not. Someone who went big whilst starting out went particularly big; @Ships and Starshas a 20" Skywatcher dob. Also a more 'grab and go' 12" version, each I believe he purchased used. Personally I have two, both are manual tracking, an 8" which receives the most use and a 14" notably for dark sky trips - which have been few and far between this past year.

Manual tracking, equatorial platform assisted tracking, or full goto and auto tracking is personal. My preference is simple, manual nudging, regardless of the subject and power used. This is or can be fine for family outreach to. You can teach a parent, nephew etc to nudge and understand, appreciate motion. Through your own physical involvement, becoming completely aware and in-tune for the the natural motion of of objects in their transit. 

Currently I have three telescopes and have only purchased two new out of a history of owning seven. Keeping an open mind for used as well as new widens the possibilities, through the usual listings; on here, Ebay and UK Astro Buy & Sell. 

[Kon]

I have an 8" Dob without tracking or GoTo. I am a beginner and I have found it very easy to track objects even at high mag. Yes they move out of view within seconds but a small nudge brings back in. Even if you decide on a longer break, the earths rotation mens that you only need to nudge or maybe refund the target by swiping rather than full search around (I tend to take a break after i had done my observation so then i can move to the next target). In terms of finding targets you will learn more with manual and it brings that excitement and frustration but you will be looking forward to the next night.  In terms of imaging, you can easily do some prime focus photography of M42 (see my post a few days ago) and you should be able to do some videos of planets for stacking later on. Finally, I have a 3 and 5 year old and they both enjoy the views through the telescope and are happy for items to move out of FOV slowly; i found that if i keep my eye on the RACI I can nudge it for them and it sort of stays in their FOV. Whichever option you go for you will have amazing views with a 16" Dob! 

)

[simonharrison]

Hi all,

Many thanks for your replies. I've been mulling it over... quite a bit! I agree £850 is a lot of money to pay for GOTO and drives. I'm happy enough without GOTO (I reckon I could find a way to mount my phone as a crude Push-To), but having the drives is the thing I really would quite like. But at £850? That could get a lot of nice eyepieces, or even a halfway decent secondhand scope on an EQ driven mount.

Equatorial platforms is a thing I'd not heard of before and I've now done a lot of googling, so thanks for that. Could I build that DIY style? Not sure - it'd have to be built strong to take the weight of even an undriven 16" like the Lightbridge (I think it's 50 kilos or so). I'd have a go though! Free time is somewhat an issue however, what with juggling work and my 7 and 5 year olds' homeschooling.

I have googled to find any info about the optical quality difference between the Meader LightBridge and the Skywatcher but what i've found is a little inconsistent, Skywatcher mirrors seem well regarded but I'm not sure what the consensus is with the Lighbridge mirrors? That could be the deciding factor.

cheers

Simon

Edited February 18, 2021 by simonharrison

[MarkAR]

Onstep is a pretty cheap option if you're good at a bit of soldering, the expensive part is if you want to use a large worm and wheel to drive it. 

I'm currently building something for a 10" newt.

https://www.backyardastro.org/topic/689-10-newt-to-dob-base/

Edited February 23, 2021 by MarkAR

[AlexK]

Welcome to the forum!

I'd ditch the GoTo idea for a 16" Dob. The platform is a nobrainer if done with some modern tech. E.g. just last weekend one of us has finished a decent design: 

And some time ago, another:

You can approach either of them for help with a platform building directly or in those threads above all the way to printing parts, which you just need to screw down to a plywood, for a reasonable compensation.

The former platform design is extremely scalable, easier to build, and nearly fool-proof, as the permanently connected rod prevents any mishaps. In addition, it's more suitable for imaging as the worm drive is fairly accurate compared to a typical roller designs.

Regarding the Lightbridge optics, it all depends on the year it was manufactured. Lately all of the common brands mirrors are made by the GSO company in China. So as both are seemingly past 2015 models for sure, their mirrors are nearly identical. Thus the quality is as usual strictly "per specimen" not "per brand". However, I would still trust Meade QC more than the SW's.

Edited February 23, 2021 by AlexK

[wobblewing]

I would be quite up for making my own 12in dob.  I'd build it onto a scaled up version of the platform above.. but the mirrors seem to be as expensive as buying a complete telescope, so not sure if it's worth it!

Edited February 24, 2021 by wobblewing

[AlexK]

2 hours ago, wobblewing said:

I would be quite up for making my own 12in dob.  I'd build it onto a scaled up version of the platform above.. but the mirrors seem to be as expensive as buying a complete telescope, so not sure if it's worth it!

Simon has already mentioned that any serious ATM is not for him at the moment. However, for the prices, I just recently procured a fast 8" mirrors set for only $130 shipped. While a 8" Dob is already way over $600 (The secret is to watch for a local stock, not shipped from China with new price tags).
Planning a couple of long postponed weird ultraportable design ideas of mine...

Edited February 24, 2021 by AlexK

[simonharrison]

Hello! I did end up buying the Meade and just posted a followup in the reviews section.

cheers

Simon

[Stu]

On 17/02/2021 at 19:43, SMF said:

Hi,

Had a very similar experience, borrowed scopes at college, got hooked, purchased 4” reflector on an eq on leaving and used that for the last 3 ½ decades.

Kids left, house/wallet allowed so treated myself, started with a 200p on eq5 a few years back and fitted it with an RA motor drive.

Wanted more so last year started looking at the same scopes as you. Particularly the 14” and 16” Skywatcher dobs with goto.

I was nervous about dobs.  I love and understand eq mounts.

Not being able to source new I ended up buying a second hand VX12L dob from another member on this forum.

Frankly it’s awesome, the extra aperture is impressive and brings back memories of my college years. The secondhand experience proved very positive.

However I absolutely loath nudging the thing. Especially at high mag. Compared to the relaxed viewing experience of an eq I’ve come to accept it’s not for me.

If Skywatcher hadn’t increased the prices so dramatically I was about to order and EQ6 size mount to try the VX12L on.

As it is, the size of increase has annoyed me on principal and I don’t get the maths. To me, the reasons they give don’t add up to such  a huge increase. I’m now planning on building an eq platform for the dob. Considering how bad the weather has been this year for the SE at least it’ll be something useful to do within the hobby on cloudy nights. In mad moments I’m even contemplating making a manual eq for it. Luckily I have access to a full machine/welding shop and an M&E background.

I find I still use the 200p particularly for planets/lunar and use the VX12L more for dso (even though it excels on planetary views).

I dapple in very rudimentary AP using an old DSLR with both scopes and find it very satisfying even if the results are basic. The eq is much better at this and a lot of fun for very little outlay, just don’t expect to compete with others on this forum let alone Hubble.

For me, RA tracking is a must for visual. Either by simple slow motion manual or motor drive.

Keep an eye on the second hand market, I found it very worthwhile for the VX12L, a 150 SkyMax and in putting together a set of Pentax eyepieces. It also suited my impetuous nature not wanting to wait up to 12 weeks once the idea is in my head.

I found half the fun was in tracking the equipment down in the classifieds at justifiable prices.

You sound like an ideal candidate for an EQ platform. Simple setup and gives you around 45 mins tracking before needing a reset that takes a few seconds. I have an 8” f8 dob which is great for planetary use but a little wobbly due to its narrow base. The platform transforms it and eliminates the need for nudging. You still find targets manually, it just gives you the tracking.

[200pman]

Good luck with your choice of dob.im happy with my 8" dob.does everything i need.

[Piero]

I would also make sure that those two telescopes can pass through the doors in your house.

The base of both the Meade and SkyWatcher dobsons is quite large (more than necessary really..).

[simonharrison]

Hi folks

@supernova I've just received an equatorial platform made by David Lukehurst. I had aimed to make one but between house move and job and kids it's time (and probably tools) I did not have...

It seems to work although I've only tried it once. Quick test with my phone (OnePlus 7 Pro) clamped to 9mm eyepiece with 30s exposure bagged the below quick shot of the Ring nebula M57.

Next step is a camera to try imaging planets, although weighing up whether to get a ZWO 224 vs 385 vs 462 vs 178 is frankly mindbogglingly confusing and I need to read many more forums first...