Expectations and deliberation

[Toaster05]

Hi all,

I'm a lapsed enthusiast looking to get back into astronomy. 

I know the night sky reasonably well and I always found the real fun to be had when observing was finding the target, this has me leaning towards a dobsonian but I'm torn regarding goto's

It's a question that will be difficult to answer I guess but any thoughts on going with the dob now and relearn the craft with a view to going for an alt az setup in the future or picking a goto for the tracking and potentially getting started with AP sooner.

My thinking is all still 20 years in the past!

Any thoughts would be gratefully accepted.

 

[andrew s]

If finding was the fun what would you expect to replace  that now with goto? If goto can give you that then that's your route if not then dob dob dob on.

Regards Andrew 

[vlaiv]

Hi and welcome to SGL.

I must say that I don't really follow what you are asking

From what I figured, you do have idea what sort of scope you want to use - you just don't know if you want goto now? Right?

You also mention AP in the future?

To be honest, in my view Dob and AP don't mix. Not because of dob mount - it's more because of telescope. There is only one telescope that is suitable to be put on dob mount and used for AP - and that is F/5 newtonian. Possibly in 6" or 8" format. Some people use 10" or even 12" Newtonian for AP, but that is huge step up and I would not recommend it for beginner in AP.

I have 8" f/6 newtonian and I did mount that OTA for astrophotography and really only used it once or twice for testing purposes. Tube is too large and heavy for Heq5 mount and acts as a sail in even slight breeze. However, I enjoy it very much as purely visual scope on manual dob mount.

Realistically what you are looking at is 6" F/5 newtonian (as there are no F/5 8" dobs as far as I know).

Getting one on dob mount is fairly easy. There is this scope:

https://www.firstlightoptics.com/dobsonians/sky-watcher-heritage-150p-flextube-dobsonian-telescope.html

However, I'm rather reluctant to recommend that scope to anyone except people on tightest budget. It is good scope for visual in everything except focuser - which is not the best. However, focuser is very important for astrophotography.

If you want to have scope that is good for visual and usable in future for astrophotography, then look at this model:

https://www.firstlightoptics.com/reflectors/skywatcher-explorer-150p-ds-ota.html

You can either DIY dob mount for it, or maybe, because it is short tube, opt for AltAZ mount for visual. This one will be very good:

https://www.firstlightoptics.com/alt-azimuth-astronomy-mounts/skywatcher-skytee-2-alt-azimuth-mount.html

If you want to "future proof" yourself from the start, you want goto and you want alt az mount for observing, you can actually get all of that if you pair above scope with either of these mounts:

https://www.firstlightoptics.com/equatorial-astronomy-mounts/skywatcher-az-eq5-gt-geq-alt-az-mount.html

or heavier version:

https://www.firstlightoptics.com/equatorial-astronomy-mounts/skywatcher-az-eq6-mount.html

Both of these work in both Alt-Az and Equatorial mode. Alt-Az is very practical for observing, and equatorial is much better for astrophotography.

 

[Toaster05]

Thanks for the replies.

I think you've helpfully answered my question Vlaiv despite my awfully worded question.

My issue is that I don't want to go down a blind alley and future proofing is really what I was looking for. 

It's more apparent to me now that what I should be doing is looking at the mount primarily as that's the fundamental element that if I get that right I can build from that to enable me to progress through observation and building up to AP in gradual manner.

 

 

[vlaiv]

9 minutes ago, Toaster05 said:

It's more apparent to me now that what I should be doing is looking at the mount primarily as that's the fundamental element that if I get that right I can build from that to enable me to progress through observation and building up to AP in gradual manner.

Indeed, mount is fundamental part in AP setup - one that you should really start with and allocate most of the budget toward.

Problem is that visual and AP don't overlap well in that area.

Visual setups favor larger aperture newtonian scopes - these are most cost effective way to get into serious observing, both planetary and deep sky.

AP setups require EQ style mount.

Newtonians on EQ style mount are ergonomically probably the worst combination . Eyepiece and finder get into most awkward positions as you point scope in different directions around the sky. You constantly need to rotate OTA in rings to overcome this - and larger the scope - quicker it becomes an issue while observing.

Having eyepiece at the front of the scope also means that you get widest range of eyepiece location heights with EQ mount.

With refractor and compound scopes where eyepiece is at the back of the scope and you have diagonal mirror - things are much more comfortable on EQ mount. You don't need to rotate whole scope - you just rotate diagonal. Range of eyepiece heights also varies less.

In order to overcome all of that - people often end up having multiple scopes and multiple mounts. This really depends on your budget.

AP is rather expensive, and that is something you should be aware from the start. It requires quite a bit of planning and thinking ahead in what you want to achieve in order not to spend too much when getting sidetracked.

Getting 8" F/6 dob for visual only while contemplating your AP journey and perhaps reading a book like this one:

https://www.firstlightoptics.com/books/making-every-photon-count-steve-richards.html

(often recommended to beginners, I have not read it myself but have confidence that sane and helpful advice is given)

is not the worst idea out there .

[Toaster05]

10 minutes ago, vlaiv said:

AP is rather expensive, and that is something you should be aware from the start. It requires quite a bit of planning and thinking ahead in what you want to achieve in order not to spend too much when getting sidetracked.

Getting 8" F/6 dob for visual only while contemplating your AP journey and perhaps reading a book like this one

I think this is a salient point. The dob seems like the right choice for now. It ticks quite a few of the boxes but as is becoming increasingly apparent no scope is ever going to tick all the boxes.

The right tool for the right job eh?

Thanks for taking the time to reply, I appreciate your greater knowledge.

[Toaster05]

Decided that I'll try and source a 10" Dob. And bide my time with regards to AP. Don't want to try and run before I can walk.

I'm lucky in that I have a large room that backs out onto my garden so manouvers should be relatively painless.

The only real issue is finding stock! Between Covid and Brexit you are more likely to spot Lord Lucan doing his weekly shop at Sainsbury's.

[andrew s]

2nd hand should be ok try here and astrobuysell uk Regards Andrew 

[johninderby]

Can’t go wrong with a 10” dob for general visual observing. Big enough to show you a lot but not too big to move around for most people.

The SW Skyliner 250px is a very good scope but the Bresser 10” is a step up in build quality and specification and has become a very popular scope indeed. Optics are similar in both scopes but worth the difference to get the Bresser if your budget allows.

Very hard to find a Bresser 10” dob second hand though as very few seem willing to let one go. 👍🏻

My Bresser 10” on a custom base.

 

Edited January 4, 2021 by johninderby

[johninderby]

Can take decent lunar images with a smartphone and a 10” dob  though.

[Toaster05]

Funnily enough the Bresser was the that caught my eye and will be the one I'm aiming for but I'll keep an open mind. Is the Bresser sold under a different name in the States? I think I read that Bresser was sold to Meade in the past then sold back to the original owners?

18 minutes ago, andrew s said:

2nd hand should be ok try here and astrobuysell uk Regards Andrew 

I will check that out. Thank you.

 

Those are some lovely lunar images. I don't think anyone could ever get tired of viewing the moon. 

[johninderby]

The Bresser solid tube dobs are (or were) sold under the Explore Scientific brand in the US.

Yes Breeser was owned by Meade for a while but bought back by the original owners with a minority share by a Chinese company.

You can spend a lifetime exploring the moon. Still my favourite even though those into AP complain when it’s out. 😁

 

Edited January 4, 2021 by johninderby

[Toaster05]

Ah that explains why I was seeing the apparent same design of mount on YouTube.

Are there any significant upgrades you've made other than the mount? I understand a better targeting solution isn't a bad idea and have seen some replacing the focusers.

[johninderby]

No real ugrades needed except for fitting a better finder. A 9x50 RACI finder and a Telrad or Rigel finder are an ideal choice.

The focuser is a really nice CNC 2.5” R&P one and no need to upgrade except for buying the optional dual speed knob.

Edited January 4, 2021 by johninderby

[John]

Popular upgrades to a stock dob are:

- replace straight though finder with a right angle, correct image one. To save back / neck ache.

- add an illuminated reticule finder alongside the optical finder. Telrad or Rigel Quikfinder are popular.

- replacement focuser - the Bresser dobs come with a better stock focuser than the Skywatchers though so not such a priority on the former brand.

- cheshire eyepiece and / or laser collimator / other tool to ease collimation.

- eyepieces (whole new topic )

The tube, mirrors and mirror cells of my Orion Optics 12 inch F/5.3 dob are still original 

 

Edited January 4, 2021 by John

[Toaster05]

Well I must say chaps, not only are you a wealth of knowledge you are really wetting my appetite to get hold of one of these.

Looking at the lead times on stock I'm clearly not alone. In the mean time I guess I'll just scour the classified and maybe I'll chance upon one.

Really appreciate you taking the time to answer my questions and post these images. Makes the buying decision that bit more informed.

Eye pieces are the bit I fear I'm going to struggle with the most. I *understand* the mechanical aspects of the scope but the eye pieces are a real blind spot if you'll excuse the pun.

Edited January 4, 2021 by Toaster05

[johninderby]

The 26mm plossl that comes with the Bresser is actualy not bad and quite usable. 

I like an 82 degree eyepiece for a dob as it keeps things in the fov for longer. The Nirvana eyepices are a great buy perform well in the dob but stock is again a problem. The Explore Scientific 82 degree eyepieces are a bit better and show up second hand nearly every day in the sales section.

BST Starguiders are a good budget option though and many will recommend them. 

Edited January 4, 2021 by johninderby

[Pixies]

Here's a good run-through of the Bresser (ES) 10" dob:

 

[John]

Be prepared to spend as much as the scope cost on eyepieces or more even, unless you are very disciplined.

Which we all are, of course !

 

[Toaster05]

I happened to watch that video and that was one of the main reasons why I was slightly confused about the Explore Scientific branding on what looked like the Bresser design.

Fortunately I have short arms and long pockets so I'll be keeping my spending in check. (I say that in full knowledge that I won't, I'm terrible)

[johninderby]

As the saying goes

“Resistance is futile”

[Toaster05]

Not entirely sure the Mrs would be in agreement but what she doesn't know eh?