The next step from 200p dobsonian

[philipw]

I'm a bit of a fair-weather observer, having had my Sky Watcher 200p dobsonian for about 3 years, and seen some incredibly things in much more detail than I hoped - I am wondering now whether to upgrade and get something bigger. I've seen the 300p Sky Watcher for about £800 and I was wondering if this would be a sensible step up and whether it would provide much more detail of planets?

 

Thanks!

[John]

You would certainly see a benefit from that additional aperture on deep sky objects. On planetary detail, on really good nights you could see more, on more average ones, maybe little or no difference

 

 

[philipw]

Thanks for your quick reply John! Is there anything else for the same money or thereabouts that would be worth considering?

[osbourne one-nil]

Here's a dull answer from me. The scope will show you more but you'll likely use it a lot less. 12" scopes are huge and a bit daunting. They're not impossible but the difference between an 8" and 12" is considerable. 

 

It'll show you more, if you used it! 

[philipw]

3 minutes ago, osbourne one-nil said:

Here's a dull answer from me. The scope will show you more but you'll likely use it a lot less. 12" scopes are huge and a bit daunting. They're not impossible but the difference between an 8" and 12" is considerable. 

 

It'll show you more, if you used it! 

The one I would buy is the flexitube, it looks less cumbersome even less so than my current 200.

 

https://www.firstlightoptics.com/dobsonians/skywatcher-skyliner-300p-flextube-dobsonian.html

[John]

5 minutes ago, philipw said:

Thanks for your quick reply John! Is there anything else for the same money or thereabouts that would be worth considering?

I'll give it some thought (as will others I'm sure). It's not an easy one though - the Skywatcher 200mm F/6 is a pretty good planetary performer. To find a scope, on a mount, that will beat it for £800 might not be that simple ....

 

[osbourne one-nil]

I've been tempted in the past and might even try one on the future. Perhaps hold on to your 8" for now though. 

 

In my experience, a 12" on a clear night on DSOs is a whole new level compared to an 8". Don't forget you'll lose some field of view, but that doesn't matter on most things. 

[philipw]

5 minutes ago, osbourne one-nil said:

I've been tempted in the past and might even try one on the future. Perhaps hold on to your 8" for now though. 

 

In my experience, a 12" on a clear night on DSOs is a whole new level compared to an 8". Don't forget you'll lose some field of view, but that doesn't matter on most things. 

I'll just have to be quicker dragging my other half from the sofa to come out and see something before it's vanished! Having the dob has really helped me find my way around the sky though.

[osbourne one-nil]

One thing to maybe ponder, do get a shroud for the scope. I've had a couple of truss dobs before and it's amazing how thermal currents ruse from your body and affect the image. My mother in law would be OK though, as she's cold blooded. 

Star hopping with a dob is fun! 

[spaceboy]

I have had 6", 8", 10" & 12" Newtonians and out of them all I still have the 8". In my opinion there is no beating the scope for ease of use while still providing enough light grasp to keep you interested. The problem is scopes get large very fast. You may only think 2" aperture increase but in truth the whole scope grows by a substantial amount. In the UK scopes sit dormant far more than they do used so storage can become an issue with larger scopes. Then there is moving big dobs about which isn't for everyone. Just my 2p worth.

[paul mc c]

I stepped up from an 8" to a 12" and there is a big difference in most things,but my only dissapointment is that i didnt keep the 8"its was a great scope and so easy to move around the garden and for a grab and go.

[AdeKing]

I have the 8" f/6 Skyliner and a 12" f/6 solid tube dob, and the 12" makes the 8" look like a pea-shooter (see photo).

1 hour ago, osbourne one-nil said:

The scope will show you more but you'll likely use it a lot less. 12" scopes are huge and a bit daunting. They're not impossible but the difference between an 8" and 12" is considerable. 

My photo does not show the size difference very well, but to give an idea, the White 8" Dob stands about 1.40m high whereas the 12" is closer to 1.80m high.  The OTA on the 8" is approximately 8.5 - 9" (215 - 228mm) in diameter whereas the 12" has a 16" (406mm) diameter tube, though this is an old Dark Star Dob with a tube of plastic drainage pipe so is probably not the norm..

A Collapsible 12" Dob will however be more compact and more easily manageable than a solid tube and one of our astronomy club regularly brings his to public outreach events.

[niallk]

The 300p would be a great performer I'm sure - a lot of scope for the money 

If a lighter/compact for transport option is of interest, it could be worth a punt on the 12" ES truss dob - but it would be another 18% on to your budget.  Worth scouring around the user reviews first...

https://www.teleskop-express.de/shop/product_info.php/info/p6879_Explore-Scientific-Ultra-Light-Dobsonian---aperture-305-mm---Generation-II.html

[25585]

1 hour ago, AdeKing said:

I have the 8" f/6 Skyliner and a 12" f/6 solid tube dob, and the 12" makes the 8" look like a pea-shooter (see photo).

My photo does not show the size difference very well, but to give an idea, the White 8" Dob stands about 1.40m high whereas the 12" is closer to 1.80m high.  The OTA on the 8" is approximately 8.5 - 9" (215 - 228mm) in diameter whereas the 12" has a 16" (406mm) diameter tube, though this is an old Dark Star Dob with a tube of plastic drainage pipe so is probably not the norm..

A Collapsible 12" Dob will however be more compact and more easily manageable than a solid tube and one of our astronomy club regularly brings his to public outreach events.

A fellow Dark Star owner! 

Mine is the F5 12 inch. Not in use as the OTA/rocker box is too heavy for my currently sore shoulder & it also needs cleaning. 

I had a 8.75 F8 Newtonian, equally heavy as it's primary cell was cast iron. Very long. 

There is a difference to brightness of anything between 8 & 12. Not just seeing fainter objects, but a much better light show generally. That goes for illuminated/reflecting objects as well as light sources themselves. Less averted vision needed for grasping at photons. 

Best though is the difference when using UHC & OIII filters. My 12" F5 was superb & really relegated the 8.75 when I used those filters. 

Currently my working dob is a 10" F5 Bresser Messier. Not as bright as the 12, better than the 8. It is less heavy to carry around so encourages use. 

Going from 8 to 10 may seem like a half step, but it's a noticable difference and does until I find a 12 which is easier to manhandle. 

[Timebandit]

 

When in comes to light grasp 

The 300p has around 100% more light gathering ability that the 200p. That is an awful lot more Light gathering ability for an extra 4" of aperture. This will help considerably on DSO objects and so is well worth the upgrade.

But viewing conditions also come into play considerably. A 200p at a true dark site will be better on most DSO than a 300p in a light pollution area. But in a head to head between the 200p and the 300p at a true dark site then the 300p will be the clear winner between the two on DSO.

If you can handle the extra size and weight of the 300p then go for as much aperture as you can afford.

I hope this helps ☺

 

 

[Nyctimene]

5 hours ago, osbourne one-nil said:

The scope will show you more but you'll likely use it a lot less. 12" scopes are huge and a bit daunting. They're not impossible but the difference between an 8" and 12" is considerable. 

OTA weight of the 200 P: 11 kg

OTA weight of the 300 P Flextube: 27 kg (+ 34 kg for the Dob mount). Somewhat similar to my old 13.1" f/4.5 Coulter Odyssey - and that's a beast to move! If you can store the 300 P in a shed/garage and attach wheelbarrow handles, or put it on a trolley, then go for it. An increase of 50% (diameter) aperture is, as an old rule of thumb, enough to show you an immediately evident substantial improvement of views. But you have to charge up the gain against the weight/bulk/setup hassles.

At any rate, I'd keep the old 200 P, if you were pleased with it up to now (in case money isn't an issue).

Stephan

 

 

 

[John]

The OP's main interest was getting better planetary views I thought

 

[scarp15]

The Flextube 300 is a great scope that can become complementary to your 200p. It can provide wonderful crisp and detailed planetary and lunar views if the seeing is steady enough, although I would not necessarily consider that this serves as its best primary function. It is more so designed to be a reasonably portable scope to transport to dark sky locations to hunt for DSO's. As mentioned, it will require a shroud and perhaps a few optional mods and upgrades. You can stop down the aperture to accommodate the seeing conditions, the main issue regarding planetary observing for the foreseeable period is the low positioning throughout the next few seasons. A dobsonian may become best situated from an unhindered vantage point, a tripod mounted refractor might serve better. In either case, away as far as possible from the thermal effects of buildings.

[Timebandit]

35 minutes ago, John said:

The OP's main interest was getting better planetary views I thought

 

 

 

?

In that case if planetary is the ultimate target. Then I would go for a nice refractor.

In my opinion I prefer refractor views of planetary and lunar than I do reflector views.

In my opinion refractor views are more crisp and sharp. I like to use the example of a good refractor view like looking at a HD television picture view and a reflector a ordinary television picture view.

 

Therefore if the OP has a budget of £800 for the scope then a nice used equinox 120ed would be the way to go. Or a standard SW 120ed are that bit cheaper. And I would mount it on a AZ4 with 2" stainless steel leg tripod . A great mount for sensible money? ?

 

 

 

[niallk]

5 hours ago, philipw said:

I'm a bit of a fair-weather observer, having had my Sky Watcher 200p dobsonian for about 3 years, and seen some incredibly things in much more detail than I hoped - I am wondering now whether to upgrade and get something bigger. I've seen the 300p Sky Watcher for about £800 and I was wondering if this would be a sensible step up and whether it would provide much more detail of planets?

 

Thanks!

Just a suggestion:

To get better planetary views in your 200p, have you ever tried or considered binoviewing?

I found this to give a very noticeable enhancement to planetary views (moon, Jupiter, Mars, Saturn) in my 250px!  Quite amazing, imho.

Fwiw, I do choose my 15" over my 250px for lunar/planets if the seeing is good - but I have to get the bigger mirror really well cooled: 2-3hrs with a fan is what I plan around.

[fiestazetecmk2]

Unless you'e got lots of money a 8" dobsonion takes some beating.by all means have a look at the larger dobs.if your taking it out and about then they do take up more room in your car.my ten pence worth.

[philipw]

1 hour ago, Nyctimene said:

OTA weight of the 200 P: 11 kg

OTA weight of the 300 P Flextube: 27 kg (+ 34 kg for the Dob mount). Somewhat similar to my old 13.1" f/4.5 Coulter Odyssey - and that's a beast to move! If you can store the 300 P in a shed/garage and attach wheelbarrow handles, or put it on a trolley, then go for it. An increase of 50% (diameter) aperture is, as an old rule of thumb, enough to show you an immediately evident substantial improvement of views. But you have to charge up the gain against the weight/bulk/setup hassles.

At any rate, I'd keep the old 200 P, if you were pleased with it up to now (in case money isn't an issue).

Stephan

 

 

 

I've been thinking about a shed in the garden with a removable roof. The 200p has been great, come on camping trips with me, fits perfectly across the back seats. I'll definitely be keeping it.

[philipw]

1 hour ago, Timebandit said:

 

 

?

In that case if planetary is the ultimate target. Then I would go for a nice refractor.

In my opinion I prefer refractor views of planetary and lunar than I do reflector views.

In my opinion refractor views are more crisp and sharp. I like to use the example of a good refractor view like looking at a HD television picture view and a reflector a ordinary television picture view.

 

Therefore if the OP has a budget of £800 for the scope then a nice used equinox 120ed would be the way to go. Or a standard SW 120ed are that bit cheaper. And I would mount it on a AZ4 with 2" stainless steel leg tripod . A great mount for sensible money? ?

 

 

 

I'm not particularly wedded to a type, would like to get better planetary views, it's what I stare open mouthed at on a clear night with my 200p although I am interested in looking deeper but that's not the primary reason I want to upgrade so I will look at the one's you've suggested. thanks!

[philipw]

1 hour ago, niallk said:

Just a suggestion:

To get better planetary views in your 200p, have you ever tried or considered binoviewing?

I found this to give a very noticeable enhancement to planetary views (moon, Jupiter, Mars, Saturn) in my 250px!  Quite amazing, imho.

Fwiw, I do choose my 15" over my 250px for lunar/planets if the seeing is good - but I have to get the bigger mirror really well cooled: 2-3hrs with a fan is what I plan around.

Sorry don't know what binoviewing is  :/

[niallk]

3 minutes ago, philipw said:

Sorry don't know what binoviewing is  :/

Ok, glad I mentioned it so!   Just a suggested option to consider.

One can insert a binocular device into the focuser which allows you to use both eyes.  The brain does amazing image processing with 2 eyes, and it can give quite a dramatic enhancement to details in planetary views. Just try closing one eye and focussing on something detailed 6ft away.

The binoviewer I have is linked below.  Try searching around SGL/Google to see reports from others on the use of binoviewers for detailed planetary views.

https://www.teleskop-express.de/shop/product_info.php/info/p475_Baader-Maxbright-Binoviewer---1-25----T2-Connection.html