Which scope, best allrounder for visual only?

[AdeKing]

As as already been recommended if you can wait then look for something like a used ED100, I managed to pick up a Celestron XLT flavoured 100ED for about £300, which would leave plenty of funds for a mount. 

But if you can't wait then don't discount the humble Startravel 102.  This was my first Frac and which I think punches well above its weight given its low cost. 

Yes it's an achromat and yes there is some CA but I personally don't find it too intrusive, the OTA is as cheap as chips and will easily sit on an AZ5. 

Admittedly It's a bit fast to be a planet killer but I've had excellent views of Jupiter and the Moon and whilst I am now fortunate enough to also own an ED100 and a Starwave f/11, the ST102 is a definite keeper and is still in regular use. 

[Neil27]

Thanks Ade that’s great to know.

Looking at FLO website I was actually considering the one above the 102 but the 127 and then upgrading the Focuser as well - this brings the total spend to just above the £600 mark but should provide some lovely views of most of what I want.

I’m just a little concerned whether the AZ5 and upgraded tripod will be up to the job, or am I better going for the sky tee 2?

And then there are eyepieces to choose as well ?, reminds me why this hobby can give you headaches and a bruised wallet sometimes ?

Thanks for sharing Ade, good to know the Startravel still is in your arsenal of scopes.

 

[Stu]

17 minutes ago, Neil27 said:

Looking at FLO website I was actually considering the one above the 102 but the 127

Are you looking at the Maks Neil? The StarTravels are 80, 102, 120 and 150mm.

[Neil27]

2 minutes ago, Stu said:

Are you looking at the Maks Neil? The StarTravels are 80, 102, 120 and 150mm.

Yep my bad, looking at the star travel 120mm - you lads are keen, just testing!

[vlaiv]

ST 120mm can almost be all rounder if you accept its limitations on planetary.

As is, it will give very poor planetary views, but you can do a couple of things that will turn it into almost decent planetary and Moon performer.

You will need two things, one is basically free of charge, while other will cost a bit of money. You will also need to accept limitations of this setup. First item that you will need is aperture mask - this one can even be fashioned out of cardboard, but you'll probably want to do plastic one, blackened on the "inside" (side facing the lens to minimize reflections). I made couple for my ST102 out of PVC pipe caps of appropriate diameter - a bit harder to cut but very sturdy. Second item that you will need is some sort of filter - like Baader Contrast Booster or Fringe Killer - anything "minus violet", even Wratten yellow #8 or 495 long pass, but last two tend to cast yellowish tone to the image.

You will need 60mm aperture mask (maybe do couple and test which one you like the best? 50, 60, 70mm - actually 50mm already comes with scope in form of hole in lens cap). With this setup you will be restricted to about x100-120 of power. Not as high power as you can go (x180-200), but will do the job. Good 5-6mm eyepiece will get you up to this magnification.

Otherwise, scope is decent performer on wide field and dso.

[JamesF]

I did think about suggesting the ST120 as a relatively low cost option when I first saw this thread, but shied away from it for the reason vlaiv alludes to.  The fringing is painfully obvious on the Moon.

Otherwise, for the money I think it's not at all bad and I use mine quite a bit because it's quite portable and can cover a lot of options.  It was my scope of choice for watching the last solar eclipse (with a Herschel wedge, but I'd have used the same OTA with a Baader white light filter if that had been all I had) and done a great deal of messier hunting with it.

When a better focuser came up second hand I did replace the stock one which has made it more pleasant to use, but that is more of a "nice to have" than a fundamental problem with the OTA.

James

[Neil27]

13 hours ago, vlaiv said:

ST 120mm can almost be all rounder if you accept its limitations on planetary.

As is, it will give very poor planetary views, but you can do a couple of things that will turn it into almost decent planetary and Moon performer.

You will need two things, one is basically free of charge, while other will cost a bit of money. You will also need to accept limitations of this setup. First item that you will need is aperture mask - this one can even be fashioned out of cardboard, but you'll probably want to do plastic one, blackened on the "inside" (side facing the lens to minimize reflections). I made couple for my ST102 out of PVC pipe caps of appropriate diameter - a bit harder to cut but very sturdy. Second item that you will need is some sort of filter - like Baader Contrast Booster or Fringe Killer - anything "minus violet", even Wratten yellow #8 or 495 long pass, but last two tend to cast yellowish tone to the image.

You will need 60mm aperture mask (maybe do couple and test which one you like the best? 50, 60, 70mm - actually 50mm already comes with scope in form of hole in lens cap). With this setup you will be restricted to about x100-120 of power. Not as high power as you can go (x180-200), but will do the job. Good 5-6mm eyepiece will get you up to this magnification.

Otherwise, scope is decent performer on wide field and dso.

Thanks Vlaiv,

A lot of really good advice provided by you and everyone else on the thread ?, I think I'll just sit tight and scour the used market and bide my time.

After reviewing all the advice given, a 4 inch ED refractor looks a good option, possibly on a sky tee 2 or similar. A couple of nice eyepieces say 5mm, 17mm and maybe a low power one for wide field (ok that’s 3 ?) and I would be very happy.

If memory serves me correct, I remember reading a book a long time ago about a guy who observed all the Messier objects just using a 4 inch refractor and although he had fairly dark skies he stated for portability and overall ease of use (for him) it was the perfect scope. We are all different and like many different things but I guess the scope you use the most and enjoy is your own ‘perfect scope nirvana’.

One last question, if a 4 inch (ish) ED refractor is my weapon of choice with say a f6.5/7 focal length like this one here - 

https://www.teleskop-express.de/shop/product_info.php/info/p4964_TS-Optics-ED-102mm-f-7-Refractor-Telescope-with-2-5--R-P-focuser.html

What eyepieces would you recommend?

Are these a reasonable choice - https://www.firstlightoptics.com/bst-starguider-eyepieces.html ?

Once again thank you for all the advice.

[Alan64]

3 hours ago, Neil27 said:

Thanks Vlaiv,

A lot of really good advice provided by you and everyone else on the thread ?, I think I'll just sit tight and scour the used market and bide my time.

After reviewing all the advice given, a 4 inch ED refractor looks a good option, possibly on a sky tee 2 or similar. A couple of nice eyepieces say 5mm, 17mm and maybe a low power one for wide field (ok that’s 3 ?) and I would be very happy.

If memory serves me correct, I remember reading a book a long time ago about a guy who observed all the Messier objects just using a 4 inch refractor and although he had fairly dark skies he stated for portability and overall ease of use (for him) it was the perfect scope. We are all different and like many different things but I guess the scope you use the most and enjoy is your own ‘perfect scope nirvana’.

One last question, if a 4 inch (ish) ED refractor is my weapon of choice with say a f6.5/7 focal length like this one here - 

https://www.teleskop-express.de/shop/product_info.php/info/p4964_TS-Optics-ED-102mm-f-7-Refractor-Telescope-with-2-5--R-P-focuser.html

What eyepieces would you recommend?

Are these a reasonable choice - https://www.firstlightoptics.com/bst-starguider-eyepieces.html ?

Once again thank you for all the advice.

That refractor looks to be an excellent value.  In choosing eyepieces, the focal-length, 714mm, is useful for planning.  For your lowest power, to complement the finder in finding objects to observe, for a cruise through the star-studded fields of the Milky Way, and ample views of the galaxy in Andromeda and the Pleiades, either a 2" 32mm 70° or 38mm  would serve nicely...

https://www.firstlightoptics.com/ovl-eyepieces/panaview-2-eyepieces.html

714mm ÷ 32mm = 22x

714mm ÷ 38mm = 19x

I'd choose the 32mm, given the very slight difference in powers.  The background of the sky would be darker with the 32mm.  It's also considerably smaller in size, yet sizable in its own right.

You'll need a diagonal.  Make it a star-prism... https://www.teleskop-express.de/shop/product_info.php/info/p9290_APM-2--Star-Diagonal-Prism-with-fast-lock-and-ultra-broadband-coating.html

The BST "Starguider" series is quite popular, and would perform to your liking.  You do want wider-angled eyepieces with a manual mount.  You might also consider barlows, a 2x, and a 3x...

https://www.rothervalleyoptics.co.uk/antares-x2-achromat-fmc-barlow-lens-125.html

https://www.rothervalleyoptics.co.uk/antares-x3-achromat-fmc-barlow-lens-125.html

I have both of those myself, and they have performed wonderfully with my telescopes, including my 4" f/8 refractor.  If you'd to bypass the use of barlows, you can get the shorter focal-lengths with larger eye-lenses through which to observe and improved eye-relief.

A 4" refractor is not too small, nor too large; a "sweet spot".  A 4" refractor is the largest of the small-refractor range which begins at 50mm(2") to 60mm(2.4").

[vlaiv]

Given refractor is nice choice, but do have a look at this one as well (probably mentioned also in this thread):

https://www.teleskop-express.de/shop/product_info.php/info/p9868_TS-Optics-PhotoLine-102mm-f-7-FPL-53-Doublet-Apo-with-2-5--Focuser.html

I think that this one (being the same in most aspects - size, weight, mechanical finish) will give you quite nicer views at high power. It is however above you budget (just shy of £900 if I'm right at conversion - that would be 50% over budget, right?). Just a thought ...

On the matter of eyepieces it would again depend on budget.

There are several factors to consider also as eyepieces are sort of personal preference. Wide AFOV? Eye relief? How important is sharpness? Etc ...

At F/7 scope can't be considered fast nor slow, so you are in the middle. I would say that you can use most eyepiece designs except those that work only in slow F/ratio (over F/9). My personal preference is for fields in range of 60-70, but I would not mind using 50 degrees eyepieces if there are budget limitations or other aspects of eyepiece are important for particular type of observation.

Do you want to go with a set, or would you consider zoom eyepiece that can cover many focal lengths?

For example, two eyepieces and a barlow might be all you need to cover most focal lengths and magnifications. ES68 28mm and Baader Hyperion Zoom IV + matching Baader barlow.

Baader zoom would cover focal lengths in range 3.5mm (maximum useful magnifications for your scope) up to 24mm (well most people use it up to 20mm as field of view gets narrow above 20mm). I just love my ES68 28mm - I use it as a low power eyepiece in all my observing scopes - true FOV a bit larger than 32mm plossl, very nice eye relief, very sharp and decent AFOV at 68 degrees.

 

[Neil27]

On 04/01/2019 at 14:20, JamesF said:

I did think about suggesting the ST120 as a relatively low cost option when I first saw this thread, but shied away from it for the reason vlaiv alludes to.  The fringing is painfully obvious on the Moon.

Otherwise, for the money I think it's not at all bad and I use mine quite a bit because it's quite portable and can cover a lot of options.  It was my scope of choice for watching the last solar eclipse (with a Herschel wedge, but I'd have used the same OTA with a Baader white light filter if that had been all I had) and done a great deal of messier hunting with it.

When a better focuser came up second hand I did replace the stock one which has made it more pleasant to use, but that is more of a "nice to have" than a fundamental problem with the OTA.

James

I think James my heart is set on a 4 inch refractor of an ED type, possibly TS or Altair scope - looking at the second hand market.

As much as appreciate the value for money the ST120 provides I think the CA would bug me after a bit.

Also with the preference for the ED 4 inch refractor they generally have quite a decent focuser already fitted.

Many thanks for the reply though, appreciated.

[Neil27]

8 hours ago, Alan64 said:

That refractor looks to be an excellent value.  In choosing eyepieces, the focal-length, 714mm, is useful for planning.  For your lowest power, to complement the finder in finding objects to observe, for a cruise through the star-studded fields of the Milky Way, and ample views of the galaxy in Andromeda and the Pleiades, either a 2" 32mm 70° or 38mm  would serve nicely...

https://www.firstlightoptics.com/ovl-eyepieces/panaview-2-eyepieces.html

714mm ÷ 32mm = 22x

714mm ÷ 38mm = 19x

I'd choose the 32mm, given the very slight difference in powers.  The background of the sky would be darker with the 32mm.  It's also considerably smaller in size, yet sizable in its own right.

You'll need a diagonal.  Make it a star-prism... https://www.teleskop-express.de/shop/product_info.php/info/p9290_APM-2--Star-Diagonal-Prism-with-fast-lock-and-ultra-broadband-coating.html

The BST "Starguider" series is quite popular, and would perform to your liking.  You do want wider-angled eyepieces with a manual mount.  You might also consider barlows, a 2x, and a 3x...

https://www.rothervalleyoptics.co.uk/antares-x2-achromat-fmc-barlow-lens-125.html

https://www.rothervalleyoptics.co.uk/antares-x3-achromat-fmc-barlow-lens-125.html

I have both of those myself, and they have performed wonderfully with my telescopes, including my 4" f/8 refractor.  If you'd to bypass the use of barlows, you can get the shorter focal-lengths with larger eye-lenses through which to observe and improved eye-relief.

A 4" refractor is not too small, nor too large; a "sweet spot".  A 4" refractor is the largest of the small-refractor range which begins at 50mm(2") to 60mm(2.4").

Thanks Alan some great advice from you, looking at your signature you have quite a few scopes and mounts, where do you store them all? 

Good idea about the barrows as well, makes 2 eyepieces into 4 potentially.

And yes I agree regarding the 4 inch being the sweet spot ... ?

[Neil27]

1 hour ago, vlaiv said:

Given refractor is nice choice, but do have a look at this one as well (probably mentioned also in this thread):

https://www.teleskop-express.de/shop/product_info.php/info/p9868_TS-Optics-PhotoLine-102mm-f-7-FPL-53-Doublet-Apo-with-2-5--Focuser.html

I think that this one (being the same in most aspects - size, weight, mechanical finish) will give you quite nicer views at high power. It is however above you budget (just shy of £900 if I'm right at conversion - that would be 50% over budget, right?). Just a thought ...

On the matter of eyepieces it would again depend on budget.

There are several factors to consider also as eyepieces are sort of personal preference. Wide AFOV? Eye relief? How important is sharpness? Etc ...

At F/7 scope can't be considered fast nor slow, so you are in the middle. I would say that you can use most eyepiece designs except those that work only in slow F/ratio (over F/9). My personal preference is for fields in range of 60-70, but I would not mind using 50 degrees eyepieces if there are budget limitations or other aspects of eyepiece are important for particular type of observation.

Do you want to go with a set, or would you consider zoom eyepiece that can cover many focal lengths?

For example, two eyepieces and a barlow might be all you need to cover most focal lengths and magnifications. ES68 28mm and Baader Hyperion Zoom IV + matching Baader barlow.

Baader zoom would cover focal lengths in range 3.5mm (maximum useful magnifications for your scope) up to 24mm (well most people use it up to 20mm as field of view gets narrow above 20mm). I just love my ES68 28mm - I use it as a low power eyepiece in all my observing scopes - true FOV a bit larger than 32mm plossl, very nice eye relief, very sharp and decent AFOV at 68 degrees.

 

Thanks for the reply Vlaiv, unfortunately although very tempting, my budget has to be a lot less than the £900 for the scope only.

I have gone from an original budget of £500 to £600, then to £600 for the scope only (if bought new) so I have to put a lid on it somewhere or I may as well get a TEC 140 and be done with it .... ?

I prefer wide field of view EP's if possible but also generous eye relief as I am a spectacle wearer. Good idea about the Hyperion zoom, I had one of those earlier in the year but sold it on after deciding i was stepping back from the hobby, only to reverse that decision ..... oh well makes shopping for astro stuff fun i guess!

Thank you for the reply really appreciate everyones times.

[Alan64]

2 hours ago, Neil27 said:

Thanks Alan some great advice from you, looking at your signature you have quite a few scopes and mounts, where do you store them all? 

Good idea about the barrows as well, makes 2 eyepieces into 4 potentially.

And yes I agree regarding the 4 inch being the sweet spot ... ?

The vast majority of my telescopes are small.  I could conceivably display them on shelves, within a bookcase, or on a wall even.  I have refractors mostly, but I like my Newtonians, too, and not necessarily for their larger apertures.  Indeed, my 114mm f/8 Newtonian is a very good simulation of my 102mm f/8 refractor...

There is that economical aspect of a barlow.  With a barlow and 3 to 4 eyepieces: 6 to 8 differing magnifications.  Although, I rarely ever, if at all, barlow an eyepiece longer than a 12mm.  With the longer, a 16mm, 20mm, or 32mm, they stand on their own.  Then, I do prefer the keep the number of glass elements down whenever possible, despite modern coatings.   Hence, a barlow might be employed with discretion; sparingly. 

Congratulations upon the decision of a refractor, even if it were a common achromat.