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New scope ideas , not a dobsonian


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Want to add a new scope to the line up at Christmas.  Very happy with my dobsonian's . OOUK VX6L and Skywatcher 200p .

Want a scope to just do Jupiter,  Saturn,  Mars and the Moon. Not bothered about imaging to much but great eyepiece views are a must . 

Budget £2000 

 

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When you say happy with your dobsonians, do you mean you don’t want another?

Many different arguments to to be had here. In theory larger aperture would give you better resolution and better views, but there are always the vagaries of the seeing conditions which can often disproportionately affect larger aperture scopes.

One problem with a £2k budget is that I assume it will need to include a mount? Something like a C925 may do the trick, or a 180mm Mak? Quite likely though that a simple 12” dob may well be better than either of these, quicker to cool and with better resolution.

I’m sure there will be plenty of differing views though!

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A Skymax 180 on an HEQ-5 comes to exactly £2k :smile:

From experience I will say a StellaLyra 12" Dob on an EQ platform will give you the best views you could ever wish for. With cash left over for some good planetary eyepieces.

My views of the moon earlier in the year at a magnification of x380 in a 4mm SLV are unmatched by anything else I've seen. Yes, it's big and heavy, but, with my bad back I can still lift it from the shed to the patio. I wish I'd done this sooner.

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For lunar and planetary views a good ED refractor would give nice views. A longer focul length one also would give give good views but you’d need a good mount to hold it on, either manual or goto manual. I have 2 ED scopes from Altair Astro, an Ascent 80ED f7 and 102ED f11 ‘fracs I use. Generally I use the 80ED ‘frac on a lighter grab and go mount for quicker set up of sessions, then use the longer f11 ‘frac on either my Skytee2 mount, or more often on my Heq5 pro goto mount. I also have a Celestron Omni 120mm f8.3 that I also use which is not an ED scope, but does give great views still. The Omni ‘fracs are discontinued now, but still come up often on the second hand market, and I got mine about 4 years ago from a member on here for about £150 if I remember rightly. All these scopes give very good double star views too. Quite a few different ED scopes available from different manufacturers etc, with varying price ranges but for 2K you should get a scope and a mount OK. 

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10 hours ago, Mart29 said:

Want to add a new scope to the line up at Christmas.  Very happy with my dobsonian's . OOUK VX6L and Skywatcher 200p .

Want a scope to just do Jupiter,  Saturn,  Mars and the Moon. Not bothered about imaging to much but great eyepiece views are a must . 

Budget £2000 

 

Do you want a larger image with more resolution than you are seeing with your current equipment or are you looking for a better contrast image with reduced light scatter, flaring and no diffraction spikes?
Also what’s your average seeing like? 

If you have average seeing and you want improved contrast something like a Starfield 4” APO with a really high end eye piece I.e Nagler zoom 3-6mm would do the trick. Honestly my 3” Tak 76DCU keeps up with MY 200P on the moon, Saturn and Jupiter. It cools much quicker and takes higher magnification in ordinary seeing, I’ve no doubt the big dob shows more but the conditions don’t allow this most of the time.

Edited by IB20
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2 hours ago, Mr Spock said:

A Skymax 180 on an HEQ-5 comes to exactly £2k :smile:

From experience I will say a StellaLyra 12" Dob on an EQ platform will give you the best views you could ever wish for. With cash left over for some good planetary eyepieces.

My views of the moon earlier in the year at a magnification of x380 in a 4mm SLV are unmatched by anything else I've seen. Yes, it's big and heavy, but, with my bad back I can still lift it from the shed to the patio. I wish I'd done this sooner.

How easy is it to polar align a 12" dob on a EQ platform? I'm imagining a lot of up and down moving from eyepiece to EQ platform as you adjust the settings.

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41 minutes ago, IB20 said:

Do you want a larger image with more resolution than you are seeing with your current equipment or are you looking for a better contrast image with reduced light scatter, flaring and no diffraction spikes?
Also what’s your average seeing like? 

 

if i just add my two pence to this @Mart29 - from personal experience it's quite expensive not answering these questions properly! :-). I love the added insight into detail in the NEB/SEB of Jupiter and the face of Saturn i get with with my 7" Cassegrain (over a 95mm short fl refractor i used before) but i HATE diffraction spikes on planets and can hardly look at Mars  as these artefacts are so bright - there is no aesthetic appreciation of the planetary body travelling through space. My eye is always aware i am looking through a telescope. You will know whether this bothers you already from the kit you have. Cheers

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14 minutes ago, Shimrod said:

How easy is it to polar align a 12" dob on a EQ platform? I'm imagining a lot of up and down moving from eyepiece to EQ platform as you adjust the settings.

I have a DIY EQ platform. As it’s for visual all you need to do is point it north and level. Once the speed is set (from a previous session on another day can be fine) there’s no more moving up and down to adjust settings. And you can use the DOB as normal. You only need to move down after about an hour when it comes to the end of its run. They are great pieces of kit. I wouldn’t be without it now and if it broke I’d immediately get/make another. 

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I note that you mention "dobsonians", i.e. more than one. For better views on those 'less than perfect' nights you could try using a smaller mask, off axis, which could give you a relatively long focus unobstructed set-up and allow more comfortable eyepieces to be used ( cost: £0 unless you buy more eyepieces to suit 🤩). A 75mm dia mask on a 200mm f/6  dob will give you focal ratio in the region of f/16 and should avoid those diffraction spikes. Although I am a dob fan, if you really want to purchase something else then I would suggest a smaller refractor which would be much more portable than the dobs for when you go on holiday ( especially abroad?).

Nigel

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14 hours ago, Mart29 said:

Want to add a new scope to the line up at Christmas.  Very happy with my dobsonian's . OOUK VX6L and Skywatcher 200p .

Want a scope to just do Jupiter,  Saturn,  Mars and the Moon. Not bothered about imaging to much but great eyepiece views are a must . 

Budget £2000 

 

Planetary detail needs resolving and this needs aperture.

To avoid being disappointed with the views - as you have two very good planetary Newtonians - I would suggest a 5” refractor as a minimum, this looks very interesting….

https://www.teleskop-express.de/shop/product_info.php/info/p10133_TS-Optics-Doublet-SD-APO-125-mm-f-7-8---FPL-53---Lanthanum-objective.html

Or you could equatorially mount your Newts like I did……

883A9950-08BF-4F1D-9B11-8C6FC00D6BB5.jpeg.157f78b89c1a989d228e0f6b10551480.jpeg

Edited by dweller25
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3 hours ago, Shimrod said:

How easy is it to polar align a 12" dob on a EQ platform? I'm imagining a lot of up and down moving from eyepiece to EQ platform as you adjust the settings.

All I do is plonk it down on the patio facing the right way and it’s good to go. No alignment required. 

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16 hours ago, Mart29 said:

Want to add a new scope to the line up at Christmas.  Very happy with my dobsonian's . OOUK VX6L and Skywatcher 200p .

Want a scope to just do Jupiter,  Saturn,  Mars and the Moon. Not bothered about imaging to much but great eyepiece views are a must . 

Budget £2000 

 

I'm not sure how much bigger you want to go, but I much prefer the views in my Skywatcher 250PX to the 200P. Combined with a Baader Hyperion 8mm modular eyepiece I was getting a crisp and large Jupiter. The only trouble I found was how fast the planet moved across the field of view when I used it at 4.3mm, giving a mag of x280!

For a scope, I am going to suggest the Skywatcher 300PDs with 1500mm focal length. I prefer the fixed tube newts to trusses or the flex tube design, but that is just my view. This scope will certainly give bright views and is capable of plenty of magnification under good seeing.

That eats up about £850 of your budget, so a fair bit left for a mount, but with a tube and rings weight of 23 kg you'll need a heavy mount. It could be a good one to put on an EQ platform, then you could just build a simple dobsonian mount for it.

If you go for this, I think I'll definitely have to make a trip out to Staffs one clear, dark night! 😁

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As mentioned above by Astrobits, making an aperture mask for one of your dobsonian's would be an interesting consideration. I made one for my 14" dob and it stops down to F11. Also as mentioned, a small i.e. around 3" refractor is tantalizingly easy to set up and take out (not that your other two scopes necessarily aren't) and 'punches above its weight' in terms of sharpness, contrast, detail and atmospheric conditions, with less cooling time. I do quite like the comprehension for just a mirror reversal and not the full inverted image as with a reflector.  

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You guys give me soooo much to think about! 🤔 😅 

Like I said , I'm happy with the dobs for sure. The views of Mars the last few mornings have being spot on.  I wouldn't get rid of the 200p , it is a great scope! The VX6L has being made redundant for the time being.

It's not necessarily better views it more I want to try something different to a dob. 

A Refractor,  a Mac etc I have only had dobs so don't know the difference.  In some conditions a Mac might be preferred to a dob. I don't know only having dobs , so my thinking was to add a different scope and then learn in different situations which is preferred.  

That said , I wouldn't want the something different to have less quality views then the dobs but also not expecting a significant or anything better. I'm fully happy with the 200p but there has to be situations where another option would work . 

Mac , Cassegrain , etc 

Looked at the Skymax 180 as @Mr Spock suggested and it might just be the one to add! 

 

 

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I bought myself a used TS-Optics Photoline 90mm FPL-53 triplet APO for Christmas pre-pandemic just to try something different.  I use it on a DSV-2B mount.  I've really enjoyed its different presentation of planets in particular from my Dob.  They seem sharper and contrastier, if a bit less ultimately detailed.  There's basically no false color in focus even at high powers.

I'd say go for a really good FPL-53/FCD-100 or equivalent doublet or triplet in the 90mm to 100mm range.  FPL-51/FCD-1 doublets show noticeable violet fringing at higher powers in my experience, so that's why avoided them as I moved up in size.  I haven't tried a triplet using these glasses, so I can't comment on them.

You'll need to leave about $500 to $700 for accessories like a 2" diagonal, an alt-az mount, and a sturdy tripod.  The nice part is, all of these can be carried over to SCTs, Maks, and CCs in the future if you want to branch out into catadioptric designs someday.

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For planetary, I think that a Skymax 180 or a C9.25 are great tools.

If you want also a GEM mount, a HEQ5 can carry both for visual/planetary (the 7" Mak is easier on the mount, but the C9.25 offers more aperture).

An electronic focuser is very helpful for good focus without too much vibration from your fingers.

N.F.

 

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