Do I need another scope?

[Helical]

Help!!

I currently own these two scopes :-

SW Skymax 102 Mak 

SW 150 p Newt.

I'm uhming and aahing as to whether to get a 3rd scope to complement the others.

I don't do imaging of any kind nor do I think it wise for me start given my personality!

I don't do much planetary viewing.

so what to get with a budget of about £500?

Cheers

ian

 

 

 

[Barry Fitz-Gerald]

Not sure that this option would overlap with your Newtonian, but one possibility is the Skywatcher Startravel 120 - an F5 achromat. For wide field low, power viewing it is very good but to elevate it to the great category it needs a couple of tweaks which could be within your budget. Decent diagonal and eyepieces for starters, the supplied ones are the cheap stock ones you get with all SW scopes. I use a 2 inch TeleVue diagonal with mine and decent wide field eyepieces an the results on DSO's are very very good. The R&P focuser it comes with is OK, but begs to be replaced with a crayford such as a GSO or TS clone. SW do a crayford that is supposed to be interchangeable with the stock one on the ST120, but that assumes you have a grinder attachment for your drill so you can shave about 1-2mm's off the focuser collar to get it into the OTA.

It is a nice little performer on the sun with a Baader Film filter and Baader Solar Continuum filter as well, where the achromatic design is of no consequence. On solar system stuff it is otherwise OK, but the CA is there and a smaller 80mm Apo like the SW DS-Pro outperforms it.

But on DSO's, the Milky Way and open clusters it is great, and at £300 for the OTA only (which is great value for money) you can afford some upgrades and still be in budget - relatively.

 

 

 

[Helical]

Thanks Barry 

Is there much CA with the Startravel? I've sort of been looking at 102-125  f7  achromatics or maybe some posh ed glass.

The thought has struck that I tend to find excuses not to take the Newt out as I struggle to find a comfortable viewing position. So I might even sell it. I've got a nice iOptron AZ Mount Pro which I actually enjoy setting up and using, its so steady.

I think I'm suffering parallaxerrs "paralysis by analysis" but that's nothing new🙄

Ian

 

Edited August 1, 2021 by Helical

[Barry Fitz-Gerald]

Well, I would say that there is probably more CA with the f5 Startravel than you would see with an f7, but to be honest with you I think on on DSO's and star fields it is largely irrelevant. I know some people do object to it, and use filters to tone the CA down such as Semi Apo or the Baader 495nm Long Pass for planetary views, but these tend to introduce a rather annoying colour (such as mustard yellow) and I prefer the unfiltered views, which on star fields can be quite sharp once the scope has cooled down and as long as you are not looking at Vega or Sirius. Maybe its just my uncritical faculties but on wide angle star fields the CA, if it is there is not a problem. I had an ST 120 and a Evostar 80ED DS-Pro (which is no slouch for a tiddler) out the other night side by side, the 80 was noticeably sharper on the moon, Jupiter and Antares - but the 120 with a cheap SBONY UHC filter bought out the Veil Nebula really well, and could start to resolve M13. If I have a grab and go session the ST120 comes out and the DS-Pro stays at home, sad but true.

You also hit the nail on the head about viewing comfort. On a simple alt-az mount (I use a FOTOMATE tripod - you mount would be 1000% better) you do not have to contort yourself to see through the EP, and I also cheat by having a laser pointer as a finder, so no back-neck ache for me thank you. I have bigger more expensive telescopes, but the 120 is one of my most used because of the sheer convenience and comfort of use. It also makes me smile when i think how cheap it was compared to my other optics, I know its not everyone's cup of tea but worth considering if your budget is £500.

"Paralysis by analysis" is part of the fun of buying telescopes - we all go through it I suspect!

Good luck!

[vlaiv]

How about 8" dob?

I agree about 120 ST mentioned above, except it will clash with 150p in what it does. It will offer a bit wider field of view a bit less coma and a bit more field curvature and CA - but in principle it will do similarly on DSOs. Advantage goes to 150p on planets and as such it is better all around scope.

8" Dob will give you all you need visually - aperture, sharpness, less coma as it is F/6 and so on - except wide field of view.

Mak102 is very nice grab'n'go scope for lunar and planetary and some DSO work

What is left is decent wide field scope - you can keep 150p, but that is a bit too much with focal length in my view. In order to be really good wide field instrument - it needs to show M31 nicely in frame . You need less than 700mm of FL in order to do that.

Alternative to 120ST would be Bresser 127 F/5 petzval quadruplet.

https://www.firstlightoptics.com/bresser-telescopes/bresser-messier-ar-127s-635-refractor-ota.html

This design eliminates field curvature and it also reduces CA in comparison to regular F/5 127mm achromatic doublet.

[Stu]

How about the ubiquitous dob? 200p or Bresser 8” would be great for DSOs

https://www.firstlightoptics.com/bresser-telescopes/bresser-messier-8-dobsonian-telescope.html

Or, if you want to scratch your apo itch, the Starwave ASCENT 102ED F7 Refractor gets great reviews at £495

https://www.altairastro.com/starwave-ascent-102ed-f7-refractor-telescope-geared-focuser-468-p.asp

[Sunshine]

Is this even a question? no amateur astronomer has uttered those words in the form of a question.

Edited August 1, 2021 by Sunshine

[Barry Fitz-Gerald]

15 minutes ago, Stu said:

Or, if you want to scratch your apo itch, the Starwave ASCENT 102ED F7 Refractor gets great reviews at £495

Much better build quality than an ST120 I suspect - no need to shell out on a decent focuser. Nice.

[Alan White]

24 minutes ago, Sunshine said:

Is this even a question? no amateur astronomer has uttered these words in the form of a question.

I did think similar myself 😉
 

[Helical]

Ok time to 'fess up OP title was deliberate clickbait 🙄 

I'm giving a lot of consideration to to this https://www.altairastro.com/starwave-ascent-102ed-f7-refractor-telescope-geared-focuser-468-p.asp..

One the reasons is that my mount an iOptron AZ Mount Pro is side mounting on the right hand side which places the finder underneath the focuser, not ideal, at least with a frac I can rotate the focuser 

[Helical]

1 hour ago, vlaiv said:

How about 8" dob?

I agree about 120 ST mentioned above, except it will clash with 150p in what it does. It will offer a bit wider field of view a bit less coma and a bit more field curvature and CA - but in principle it will do similarly on DSOs. Advantage goes to 150p on planets and as such it is better all around scope.

8" Dob will give you all you need visually - aperture, sharpness, less coma as it is F/6 and so on - except wide field of view.

Mak102 is very nice grab'n'go scope for lunar and planetary and some DSO work

What is left is decent wide field scope - you can keep 150p, but that is a bit too much with focal length in my view. In order to be really good wide field instrument - it needs to show M31 nicely in frame . You need less than 700mm of FL in order to do that.

Alternative to 120ST would be Bresser 127 F/5 petzval quadruplet.

https://www.firstlightoptics.com/bresser-telescopes/bresser-messier-ar-127s-635-refractor-ota.html

This design eliminates field curvature and it also reduces CA in comparison to regular F/5 127mm achromatic doublet.

Hi vlaiv thanks for the suggestions, the bresser 127 looks really interesting, need to research that a bit more. 

Ian

 

[niallk]

How about save up a bit more, and consider solar Ha?...!!

[Stu]

2 hours ago, Sunshine said:

Is this even a question? no amateur astronomer has uttered these words in the form of a question.

Yes, the title does need changing to ‘Which scope do I need next?’ or similar 😉

[Stu]

30 minutes ago, Helical said:

Ok time to 'fess up OP title was deliberate clickbait 🙄 

I'm giving a lot of consideration to to this https://www.altairastro.com/starwave-ascent-102ed-f7-refractor-telescope-geared-focuser-468-p.asp..

One the reasons is that my mount an iOptron AZ Mount Pro is side mounting on the right hand side which places the finder underneath the focuser, not ideal, at least with a frac I can rotate the focuser 

Yep, that was one of my suggestions 👍

That or an 8” dob I would say.

[Helical]

3 hours ago, niallk said:

How about save up a bit more, and consider solar Ha?...!!

Not sure I'd be too popular peering up at Solar prominences when the lawn needs mowing! However a solar filter on a frac would be good for sun spots methinks 🤔

[Helical]

Well I've been and gone and pulled the trigger on this https://www.altairastro.com/starwave-ascent-102ed-f7-refractor-telescope-geared-focuser-468-p.asp from Harrisons. Hope the dew shield is effective after last night's moisture fest!