24 replies to this topic

[wishmaster]

Hi, it's been a while. I'm considering buying myself a refractor because i love refractors and long focal ratios. My limited budget allows me something in the 80mm - 100mm range. I wonder if should i go with modern achromats like Omni XLT 102mm or stick with the classic ones, say, Towa 339 80mm f/15 or a Vixen 90M. Refractors are not so long these days and i mainly think of using the scope for moon and planets (including decent views of Mars), so is a difficult decision. Maybe i would once in a while, use a webcam for taking a planetary video, but mainly for visual joy. I like the oldschool refractors very much, like Vixen 80M or 90M. How about a Vixen 90M/Towa 339 vs Omni XLT 102?

 

Best regards.

Edited by wishmaster, 15 February 2025 - 09:16 PM.

[PKDfan]

Hi wishmaster !

If I was looking for an achromat it definitely be a classic proven and probably very nicely polished Japanese craftsmanship Vixen or Towa despite never looking through either one the reviews are unequivocable.


Best of luck !


I hope your first observations have


Clear & Steady Skies
Lance

[The Ardent]

The 90M or any classic Vixen refactor is a good option. 
Baader has a 1.25” visual back for these scopes. 

 

Baader 1.25" Eyepiece Holder with 36.4mm Vixen Male Thread

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[wishmaster]

The 90M or any classic Vixen refactor is a good option. 
Baader has a 1.25” visual back for these scopes. 

 

Baader 1.25" Eyepiece Holder with 36.4mm Vixen Male Thread

Gorgeous scope. Have you tried maybe some webcam imaging on it? How many magnification are you able to push for planets without having too much CA?

 

Thank you.

Edited by wishmaster, 15 February 2025 - 10:02 PM.

[The Ardent]

This was taken at our public night. Using 7mm eyepiece for 143x on Saturn. CA was slight and not an issue at all. Have not used since due to weather. No imaging sorry.

[jimeh]

A lot of people who like vintage long focal length refractors have found their way to the TS or Altair f/11 102ED. If you have a mount that can accommodate it, I would bypass the Omni xlt 102 entirely.

 

My Celestron/Vixen 90 was a great scope, but I'm much happier with the f/11 102ED.

[wishmaster]

A lot of people who like vintage long focal length refractors have found their way to the TS or Altair f/11 102ED. If you have a mount that can accommodate it, I would bypass the Omni xlt 102 entirely.

 

My Celestron/Vixen 90 was a great scope, but I'm much happier with the f/11 102ED.

All i can find on eBay is 102ED f/7 SvBony short refractors. Are these any good for planets I'm not particularly interested in astrophotography, maybe some imaging of planets or moon craters with my old webcam. It sounds like long focus achromats would be easier to push to high magnifications without having to spend a fortune in barlows or short focal length eyepieces, not to mention splitting doubles.

 

Thanks for the info btw.

[k5apl]

Hi

I can recommend the Classic Telescopes Forum for advice on old scopes...some are better than others.  I have a

variety of refractors, but several are 60mm diameter.  I do have a Stellarvue 80/9D achro refractor that I like very much, and it was inexpensive.  I do own a 92mm A-P Stowaway too.  I think you are on the right track with a 80mm to 100mm size telescope.  Considering the size and mount, I'd look harder at 80-90mm scopes.  There are some

bargains to be had by watching CN Classifieds.  Have fun deciding.

Wes

[nic35]

An option

 

https://www.youtube....h?v=491fuvFWJSg

 

john

[Jethro7]

Hi, it's been a while. I'm considering buying myself a refractor because i love refractors and long focal ratios. My limited budget allows me something in the 80mm - 100mm range. I wonder if should i go with modern achromats like Omni XLT 102mm or stick with the classic ones, say, Towa 339 80mm f/15 or a Vixen 90M. Refractors are not so long these days and i mainly think of using the scope for moon and planets (including decent views of Mars), so is a difficult decision. Maybe i would once in a while, use a webcam for taking a planetary video, but mainly for visual joy. I like the oldschool refractors very much, like Vixen 80M or 90M. How about a Vixen 90M/Towa 339 vs Omni XLT 102?

 

Best regards.

Hello wishmaster,

Some of the old classic achros like the Goto Kogaku, Takahashi and Unitrons have really nice optics. That can be truly realized using modern diagonals and eyepieces but these scopes command APO prices when ever you find them. The modern Achros will outclass most all other classic Achros, such as the Towa's  Like Jimeh, posted, the Altair Starwave 102ED F/11 also known as the TS Optic 102ED F/11 (TS Optics has a version with a Lanthanum element) The Altair 102ED F/11, way out performs its price point and was my favorite Lunar and Planetary scope for years. 

 

HAPPY SKIES AND KEEP LOOKING UP Jethro

 

Here is a long running set of Altair Starwave 102ED CN Threads.

https://www.cloudyni...2ed-f11-yes-ed/

 

My Altair Starwave 102ED F/11 in tandem with a Atrotech 102ED F/7 for size comparison. 

 

 

 

Edited by Jethro7, 15 February 2025 - 11:23 PM.

[Dave Novoselsky]

Want a modern take on the 80 and 90L?  Kasai Jscope 80 f15.  All except the focuser, which is a very nice 2 speed I believe Taiwan sourced, is hand built in Japanese by craftsman.  The optics are great and use modern coatings.  Reasonable price and not more than you will pay for a pristine Vixen 80 or 90L f13.4.  Visually superior given the modern coatings.

 

Agena had one in stock last time I checked as did FLO in the UK.  I bought mine directly from Mr. Kasai who has an English version of his website and communicates fluently in emails he responds to promptly.  He exports to the US etc regularly and can arrange payment and shipping.  Plus he is an avid astronomer himself.

 

i love mine and use it side by side with my vintage long focal length Vixen collection.

[Martinbruce]

There is a TS Optics 102mm f/11 scope in the classifieds right now. Pictures look good. Somewhere in Texas for $675. I have no knowledge or affiliation with the advertiser. Might be worth looking into. Perhaps it is this one?

 

https://www.teleskop...p-focuser-11262

 

Good luck. 

[wishmaster]

Good lord, it all comes down to either the Takahashi Starbase 80 or the Kasai Jscope 80L. Which would perform better? I think the Tak comes with the whole package and mount, the Kasai is OTA only and it is long. This is driving me crazy.

 

Thanks!

Edited by wishmaster, 16 February 2025 - 01:31 PM.

[nic35]

Good lord, it all comes down to either the Takahashi Starbase 80 or the Kasai Jscope 80L. Which would perform better? I think the Tak comes with the whole package and mount, the Kasai is OTA only and it is long. This is driving me crazy.

 

Thanks!

Yes, the Starbase 80 comes with everything, including eyepieces. The Kasai needs a tripod and some kind of mount.  Look at the SVBony 225 mount and an Artcise tripod - light weight.  Adds about $350 to the purchase price if from amazon.  Plus eyepieces.

 

Of course Ed Ting suggests another eyepiece for the StarBase, as well as some kind of finder.  Probably an additional $100.

 

I suspect the Kasai probably gives a slightly better image, but it may not be discernably different.

 

j

[wishmaster]

Yes, the Starbase 80 comes with everything, including eyepieces. The Kasai needs a tripod and some kind of mount.  Look at the SVBony 225 mount and an Artcise tripod - light weight.  Adds about $350 to the purchase price if from amazon.  Plus eyepieces.

 

Of course Ed Ting suggests another eyepiece for the StarBase, as well as some kind of finder.  Probably an additional $100.

 

I suspect the Kasai probably gives a slightly better image, but it may not be discernably different.

 

j

I was considering the combo Kasai Jscope 80L (which is seems to be excellent optically for an achromat) + chinese EQ3 equatorial mount. For what a read it supports a higher payload than the Kasai OTA. And then maybe in the future i'll get some more decent mount with tracking or a dual head one for a secondary scope.

 

What really is intriguing to me is that all of the Japanese preimum 80mm achromats (Towa 339 and others) are 80mm f/15 1200mm. I think it is a Fraunhofer doublet right? Maybe the only differente between the Towa 339 and the Kasai Jscope (besides the years apart) in comes down to multicoating processes and might be some polishing processes. But it seems to be rather the same proven-to-be-excellent optical system, right?

 

That is optically speaking only. You get a far better focuser and mounting plate on the Kasai for example.

 

Thanks a lot.

[wishmaster]

I finally ordered de Kasai JScope 80L. Thank you very much for all your comments and experiences. I may write a review or post a picture of it once i put my hands on it.

 

Best regards.

[Mike W]

All i can find on eBay is 102ED f/7 SvBony short refractors. Are these any good for planets I'm not particularly interested in astrophotography, maybe some imaging of planets or moon craters with my old webcam. It sounds like long focus achromats would be easier to push to high magnifications without having to spend a fortune in barlows or short focal length eyepieces, not to mention splitting doubles.

 

Thanks for the info btw.

The SV503 102 ED is a very nice scope, easier to mount than a longer refractor. 

[kmparsons]

I love long-focus achros and have several. I see you have made your choice, and I think it is a good one. For me, if I were getting a long focus refractor now I would go with the Altair Planeta, which has an ED doublet objective:

 

https://altairastro....ope-13522-p.asp

[wishmaster]

Well, finally it arrived. I quick tested it with the Moon, Alpha Centauri and Mars. Good lord. You can see the diffraction pattern instantly. The focus is super fine despite the mount i have is not a good mount. But i'll craft a pier mount in my backyard for sure. The star test resulted in virtually identical intra and extra focal star image, very simmetrical and stable patterns. I'm no expert in star testing telescopes, but i liked very much what i saw. I observed the Moon, Mars under average seeing and Mars disk edge was super clear and noticeable but only in 120x using regular/medium quality eyepieces. I ordered a couple of basic Vixen eyepieces that have not arrived yet. The telescopes thermal behavior is excellent, the image stood very quite and the level of detail i could see on the Moon was breath taking although being nearly full. The same thing happened this noon when i put a baader filter cap and pointed to the Sun, i could clearly see photosphere detail, white fringes, awesome sunspot detail in perfect focused images. I wrote Mr. Kasai to thank him for this awesome instrument. I'll write up some more experiences in the refractor telescope forum. Thank you all for the advice and specially Dave for your advice on this awesome modern take on the Japanese long refractor tradition.

 

Cheers.

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[Kitfox]

Just beautiful...

[zjc26138]

Congrats! That is a great looking scope!

[williamc]

Hi, beautiful telescope, congratulations! I was curious about the mounting you're using. Looks like a nicely made, basic mount for a small scope, but I don't recognize it. Can you identify the mount?

 

William

[Dale Fish]

I recently purchased an old (90’s production) MEAD 102ACHR/500 102mm, 920mm fl (f/9) from our club. They were clearing out some scopes from the lending library. I’ve had it out a few times and I have to say I’m really enjoying it. I hate to say it, but I think I like it way better than my Celestron C6. Am I crazy? I still need to make a custom mounting bracket for it.

[wishmaster]

Hi, beautiful telescope, congratulations! I was curious about the mounting you're using. Looks like a nicely made, basic mount for a small scope, but I don't recognize it. Can you identify the mount?

 

William

It is a SkyOptikst cheap chinese mount just to mount it on something. I'll make a pier mount surely with my electric welder for my backyard maybe using the monut head or getting a heavier one, i don't know yet. The monut is compatible with the vixen style dovetail whatsoever which is good enough. It is a EQ3 type mount --> https://www.ebay.com/itm/145946854145

 

Cheers.

[Jethro7]

It is a SkyOptikst cheap chinese mount just to mount it on something. I'll make a pier mount surely with my electric welder for my backyard maybe using the monut head or getting a heavier one, i don't know yet. The monut is compatible with the vixen style dovetail whatsoever which is good enough. It is a EQ3 type mount --> https://www.ebay.com/itm/145946854145

 

Cheers.

Hello wishmaster,

Update, I pulled the pigs tail this morning with this scope

https://telescopes.n...t-b1200r-p.html. In Stock, YAY!!!! I will purhase the Double stack Etalon soon. 

 

The mount that I will be using, is either my Desert Sky Astro DSV-2 or SV M002C or my DM6 for that matter. Thanks to Celestron  (Awesome Customer Service) I'm totally done with cheap mounts. If I find that using a manual Alt/Az mount problematic, I will look at other tracking mounts. I have an ongoing interest in the up and coming Pegasus SmartEye, and would think that a ZWO AM-3/ AM-5 or the like would be a good choice for the Smarteye, as well as good choice for the Solar scope. For me the benefit of having a light weight mount would be having a light weight mount.

 

HAPPY SKIES AND KEEP LOOKING UP Jethro

Edited by Jethro7, 14 May 2025 - 10:51 AM.