41 replies to this topic

[raylinds]

I finally succumbed to the allure of a refractor and purchased an Astro-Tech 115EDT. I has gotten good reviews and I am very happy with my AT EPs. I made the purchase for a few reasons, 1) at 67 with a bad back, carrying around the big tube with EQ-6, was no longer an option, and 2) for many situations the long focal length complicated matters, especially if I wanted to do EAA or AP (right now I do mainly visual). I will probably keep the 9.25" for planetary and dim DSOs, but will probably do most viewing with the 115.

 

My AM5 handles the 9.25, so should not have a problem with the refractor. I might actually get to use my TV 3-6 mm Nagler zoom!

 

I would be interested in hearing about the experience of others making the SCT to refractor transition.

[Sheremy01]

I have a C11 edge and picked up the AT86EDQ and even though it’s much smaller in aperture it’s much easier to get good images out of it. Focus is so much easier and stars are nicer. Its actually made me just wonder if I have a bad copy of the C11 or if the Astro tech is just that much sharper. I’ve check collimation and it looks spot on to me. It’s convinced me to buy the AT126EDQ once it’s in stock.

Edited by Sheremy01, 06 July 2025 - 04:14 PM.

[Astro-Master]

I finally succumbed to the allure of a refractor and purchased an Astro-Tech 115EDT. I has gotten good reviews and I am very happy with my AT EPs. I made the purchase for a few reasons, 1) at 67 with a bad back, carrying around the big tube with EQ-6, was no longer an option, and 2) for many situations the long focal length complicated matters, especially if I wanted to do EAA or AP (right now I do mainly visual). I will probably keep the 9.25" for planetary and dim DSOs, but will probably do most viewing with the 115.

 

My AM5 handles the 9.25, so should not have a problem with the refractor. I might actually get to use my TV 3-6 mm Nagler zoom!

 

I would be interested in hearing about the experience of others making the SCT to refractor transition.

I only have one place in my light polluted back yard to observe without trees and it's up a flight of 16 stairs. 

 

I sometimes use my 10" SCT or C8 on a CGEM II that stays in the upper yard, but most of the time I use my Stellarvue 105mm Triplet on Double stars and Carbon stars because the star images are so perfect in the APO using my Nagler 3-6 Zoom.

 

I think you will also find the TV Zoom is awesome for Double stars in your AT 115 to dial in just the right power for the seeing conditions or to split a tight double.  

[Astromancer]

I finally succumbed to the allure of a refractor and purchased an Astro-Tech 115EDT. I has gotten good reviews and I am very happy with my AT EPs. I made the purchase for a few reasons, 1) at 67 with a bad back, carrying around the big tube with EQ-6, was no longer an option, and 2) for many situations the long focal length complicated matters, especially if I wanted to do EAA or AP (right now I do mainly visual). I will probably keep the 9.25" for planetary and dim DSOs, but will probably do most viewing with the 115.

 

My AM5 handles the 9.25, so should not have a problem with the refractor. I might actually get to use my TV 3-6 mm Nagler zoom!

 

I would be interested in hearing about the experience of others making the SCT to refractor transition.

I purchased an AT115EDT last year to complement my 8” Meade SCT. I too have an AM5 and it almost laughs at being asked to handle the (relatively) light weight AT115 after the SCT. I have now moved up to a Celestron 9.25” SCT, but still find the refractor “crisper” and much easier to focus.

[bobhen]

For most of my over 40-years of observing, I've had both an SCT (8", 10" & 11") and a refractor (80mm to 155mm). A few years ago, I downsized (also age and back issues) from an Astro-Physics 155 F7 and a C11 to a Takahashi TSA 120 F7.5 and a C8. Refractors and SCTs do different things. But if I were forced to pick just one scope, it would be a rather easy decision. The refractor (in this case the Tak TSA 120) would stay.

 

1.The lack of light gathering in the TSA 120 compared to the C8 can easily be made up and surpassed with the use of an image intensifier or camera for doing EAA.
2. The C8 has more raw resolution but the optics in the TSA 120 are much better and the TSA 120 bests the C8 on the planets.
3. The TSA 120 is the better solar white light and Ha telescope.
4. Although the C8 is more compact, both the C8 and the TSA 120 use the same mounts – so there is no portability advantage to the C8.

 

For the moment, I'm lucky to have both.

 

Bob

[t.r.]

I don’t know if transition is the right descriptor for me, because I seem to have kept both sct and refractor to compliment each other through the years. First was a C8 and a Televue Genesis, where I confirmed early on that yes, there is something magical to refractors. Later, paired a C11 with a TEC 140 and reaffirmed that there was some magic to pairing these telescope types. Is the next step a C14 and an AP or TEC 7”?! Maybe but time and opportunity (my back!) are running out! If forced to pick just one, it would by my AP 140, it has the better than the light gathering capability of a 6” reflector, which is said to be able to show every class of astronomical object to keep one busy for a lifetime!

Edited by t.r., 08 July 2025 - 12:56 PM.

[Oldfracguy]

I finally succumbed to the allure of a refractor and purchased an Astro-Tech 115EDT. I has gotten good reviews and I am very happy with my AT EPs. I made the purchase for a few reasons, 1) at 67 with a bad back, carrying around the big tube with EQ-6, was no longer an option, and 2) for many situations the long focal length complicated matters, especially if I wanted to do EAA or AP (right now I do mainly visual). I will probably keep the 9.25" for planetary and dim DSOs, but will probably do most viewing with the 115.

 

My AM5 handles the 9.25, so should not have a problem with the refractor. I might actually get to use my TV 3-6 mm Nagler zoom!

 

I would be interested in hearing about the experience of others making the SCT to refractor transition.

Two years ago I decided to try out SCTs.  I had two C8's over a period of several months, one of which I went all-out with the "Reflectix" treatment and black flocking sheet lining the inside of the long dew shield I made for it.  I had it outside one night along with an AT115EDT that I was able to collimate quite well (they do have collimation screws on the back edge of the objective cell).  The only thing the C8 did better than the AT115EDT was show more stars in clusters, especially globulars.  Over a period of several weeks the AT115EDT repeatedly dusted the C8 on the planets, the lunar surface, and especially double stars.  I was observing from home under severely light polluted skies, and I'm sure that under dark skies the C8 would have outperformed the AT115EDT on galaxies and faint planetary nebulae.  Another thing about the AT115EDT that I suppose I like the best is that its front corrector plate does not dew up at the drop of a hat.  I sold the C8 soon after.

Edited by Oldfracguy, 08 July 2025 - 01:38 PM.

[Sacred Heart]

I started out being a Maksutov guy, a 7" and 3/5". Then came a C14. I had a SBIG CCD camera, but never could take an image.  Although I did squeak out planetary shots with a webcam. That was 1999 to 2019.  When 2019 rolled around I bought some refractors, a 76mm and a 92mm, a CMOS camera too.  What a difference 20 years makes, Youtube videos and support groups.  Success right off the bat. In fact a few years later I bought a 130mm refractor, three cooled CMOS cameras and a few decent eyepieces.

 

Bottom line, I gave the C14 away, still have the Mak's but hardly use them.  I'm refractor all the way now. Not looking back either.

 

My story,  Joe

[raylinds]

I always thought it was all about higher magnification for planets and most DSOs. So what is it about refractors that make them excel at even some of those targets? I'm sure I'll find out when I get it the end of the week, but was interested in other's opinions.

[Oldfracguy]

I always thought it was all about higher magnification for planets and most DSOs. So what is it about refractors that make them excel at even some of those targets? I'm sure I'll find out when I get it the end of the week, but was interested in other's opinions.

The difference is reduced residual light scatter compared to that inherent in any mirrored telescope, as well as improved contrast due to no central obstruction.  Last night, in fact, I was looking at M27, the Dumbbell Nebula, using a 150mm f/6 Newtonian with a 33% CO and a little Astro-Tech AT70ED refractor using the same DGM NPB Narrowband filter in each scope.  I was amazed at how similar the views were in both scopes, using different eyepieces that yielded about the same magnification and TFOV in each scope.  I had thought the 6" Newt would have totally been able to show more of the overall shape of the nebula that gives it its famous name, but to my pleasant surprise I could make out the general shape in the much smaller ED refractor as well.  That was from home under Bortle 8 skies.

Edited by Oldfracguy, 08 July 2025 - 05:45 PM.

[Sacred Heart]

I always thought it was all about higher magnification for planets and most DSOs. So what is it about refractors that make them excel at even some of those targets? I'm sure I'll find out when I get it the end of the week, but was interested in other's opinions.

To me, speaking on planets, the refractor is easier to focus and can deliver clean clear crisp views.  Seeing dependent, in my sky my 130 I can use my 3 - 6mm zoom at 4mm most nights and retain that detail.  

 

On deep sky objects, the 130 can deliver wide field views of the Double Cluster and can split the Double Double in Lyra with the right eyepiece.  Put the UHC filter in front and the Lagoon Nebula pops out more.

 

The refractor s an extremely versatile scope.  It can't do everything, but it can do a lot.  Ever notice there are posts that compare small refractors, 4" maybe up to 5" and smaller to larger Cassagrains.

 

Imaging or viewing, refractors are fun to use.  I like fun.

 

My opinions,  Joe

[rjacks]

I have a C8 and an AT115EDT, and I regularly use them both and like them for different reasons. I don't think one needs to pick one over the other. 

 

That being said, I have never seen the AT115 provide the detail in either Jupiter or the moon that I can get from the C8 at the same magnification. However, there is a lot more variation in the quality of C8s than there is in AT115s, so the comparison depends on the C8.

 

Comparisons really need to be made under the same seeing conditions at the same magnification.  

 

For me, the strength of a refractor lies in wide field views and scanning the Milky Way. 

[stargzr66207]

I guess I'm a member of this club too. After 20 years observing and imaging with an observatory mounted C-11, I'm now using an AstroTech AT92 92mm f/5.5 APO refractor. With a native focal length of 506mm, it has the same field and image scale as the C-11 using HyperStar, but is SO much easier to image with.  Much tighter stars and lower HFR, too. I love it!

Ron Abbott 

[MCX2]

I am curious how you find the AM5 with the AT 115.  I have the Meade 115 version of it and an AM3 (which should handle the weight) but I have never used the two together because I am concerned about not having enough clearance with the tripod legs, even with the pier.

[PKDfan]

I finally succumbed to the allure of a refractor and purchased an Astro-Tech 115EDT. I has gotten good reviews and I am very happy with my AT EPs. I made the purchase for a few reasons, 1) at 67 with a bad back, carrying around the big tube with EQ-6, was no longer an option, and 2) for many situations the long focal length complicated matters, especially if I wanted to do EAA or AP (right now I do mainly visual). I will probably keep the 9.25" for planetary and dim DSOs, but will probably do most viewing with the 115.

My AM5 handles the 9.25, so should not have a problem with the refractor. I might actually get to use my TV 3-6 mm Nagler zoom!

I would be interested in hearing about the experience of others making the SCT to refractor transition.

In other words you upgraded considerably Ray ! Congrats on the new scope- seems a stunner !

I had a superb C8 but my much smaller apo annihilated it and it wasn't even close.

Total preservation of colour data by lense trumps mirror scatter nuance detection. Kinda need a gooder to do the job is the only prerequisite required.

Its impossible to capture my Evolux capability digitally so i'm thinking of cobbling my medium format camera with an adapter for slide film.

Of course that'll take forever but really the only way to get the contrast signal depth it generates.

Quite the amazing imagery from Some of todays straight on systems.

No comparison can be made IMO.


Lance
CSS

[Procyon]

Keeping my CPC 1100 but refractors are great fun!

Added a 100mm and 120mm refractor for Asterisms, large Open Clusters and Starfields.

Perfect grab n go with a small goto mount. Just visual.

 

The amount of stuff one can see from a dark backyard with an 100mm...every night out

with a refractor is a blast, especially when I don't have to carry the gorilla back home.

Edited by Procyon, 08 July 2025 - 10:29 PM.

[PKDfan]

Keeping my CPC 1100 but refractors are great fun!
Added a 100mm and 120mm refractor for Asterisms, large Open Clusters and Starfields.
Perfect grab n go with a small goto mount. Just visual.

The amount of stuff one can see from a dark backyard with an 100mm...every night out
with a refractor is a blast, especially when I don't have to carry the gorilla back home.

A C11 was my dream scope for ages growing up as a kid Tom.

Looked at M13 once with a C14 and OMGing doesn't even come close to how i felt.

When i sold my C8 and took a hiatus from astronomy, then much later reinvested in a refractor, i thought my F/9 100mm would somehow be several steps down in ability when actually it was several steps up.

Took me FOREVER to believe that its capabilities were as good as what it was.
Except for small galaxies and the ubiquitous globulars it easily bested the very good C8 i had in every regard. My view of ngc 2024 at B2 skies was literally a long exposure Astro Photo that i still see 'flaming' in my minds eye.


Don't get rid of that C11 behemoth just yet Procyon but get yourself a F/9 100mm Evostar and prepare for your world to be turned sideways upended and twisted into unrecognizable shapes.

Aperture isn't everything folks so allow yourself to let go of the notion that only 4inches is going to be a let down.

If you were close i'd get both of my apos together for you to marvel at.

I'm CONSTANTLY shocked at just how much detail 62mm of perfect chromatic excellence shows except lol on globs and faint galaxy smudges. Half dozen branches of Triesnecker rille system for instance.

I dream of B1 skies with them.

My F/9 sweeps with Al's 20mm T2 Nagler (45X) at sagittarious and scorpio was the stuff of astro fantasies.

Not all apertures are created equally Tom and i'm pretty sure a true Lover of the night skies will be blessed to get a 'gooder' scope that does so much more than what the little numbers mean on the surface.


Cheers !!

Lance
CSS

[Procyon]

Will never get rid of the CPC 1100. It's like my office. Will never get rid of refractors either. Now I just need to add a 130mm Newtonian and I'm done : )

[Oldfracguy]

Will never get rid of the CPC 1100. It's like my office. Will never get rid of refractors either. Now I just need to add a 130mm Newtonian and I'm done : )

The one to add would be this one, the Sky-Watcher 130PDS:

 

 

 

It has a 2" dual-speed Crayford focuser.  I still remember the views through a 2" 28mm 82° UWA eyepiece in a Coma Corrector with this scope.  For medium-to-low power views it is a great little scope.

Edited by Oldfracguy, 09 July 2025 - 01:07 PM.

[Procyon]

The one to add would be this one, the Sky-Watcher 130PDS:

 

101_1203.JPG

 

 

It has a 2" dual-speed Crayford focuser.  I still remember the views through a 2" 28mm 82° UWA eyepiece in a Coma Corrector with this scope.  For medium-to-low power views it is a great little scope.

Why do you always have every scope I want lol.

Yeah, that's the one.

Nice pic : )

 

How would you compare it say to an Orion/Skywatcher 120mm Achro?

Ever looked at blue stars with it?

Edited by Procyon, 09 July 2025 - 02:12 PM.

[Oldfracguy]

Why do you always have every scope I want lol.

Yeah, that's the one.

Nice pic : )

 

How would you compare it say to an Orion/Skywatcher 120mm Achro?

Ever looked at blue stars with it?

That SW 130PDS went toe-to-toe with an AT115EDT up to about 130x (5mm eyepiece).  After that the AT115EDT pulled away at higher magnifications.  You will see true star colors with these Newtonians, and Zero CA.  The only issue is that the central obstruction puts a limit on the Exit Pupil size of about 6 mm.  For wide-field views with 2" eyepieces a Coma Corrector is required, and that will increase the effective focal length and focal ratio somewhat, so maybe a 32mm eyepiece might be the longest focal length usable with a typical Coma Corrector.  The maximum achievable TFOV will be smaller with SW 130PDS than with a ST120.  

Edited by Oldfracguy, 09 July 2025 - 02:48 PM.

[PKDfan]

Will never get rid of the CPC 1100. It's like my office. Will never get rid of refractors either. Now I just need to add a 130mm Newtonian and I'm done : )

I like you very much Tom but i just can't give this post one.

What on earth would a occluded 130mm Newtonian possibly offer you ?

I can totally understand that marvelous C11 but unless your just starting out it seems to me its just a waste of money...says the snooty refractorphile.

Maybe as a rich field scope i could see a use for one ?

You don't have to explain your rationale to me as just because its a telescope is reason enough but a good 4inch refractor will trounce it, blindfolded.


Are you Gasp a collector of tubes ? I have a friend who admitted he has 50 of them. TELESCOPITIS DISEASE can be succinctly described as a blind spot in your peripheral vision where you lose sight of how many scopes one actually has.

Nasty expensive predicament !


Lance, a fellow sufferer but in eyepieces instead.


Clear STEADY ON Skies

[Highburymark]

For most of my over 40-years of observing, I've had both an SCT (8", 10" & 11") and a refractor (80mm to 155mm). A few years ago, I downsized (also age and back issues) from an Astro-Physics 155 F7 and a C11 to a Takahashi TSA 120 F7.5 and a C8. Refractors and SCTs do different things. But if I were forced to pick just one scope, it would be a rather easy decision. The refractor (in this case the Tak TSA 120) would stay.

1.The lack of light gathering in the TSA 120 compared to the C8 can easily be made up and surpassed with the use of an image intensifier or camera for doing EAA.
2. The C8 has more raw resolution but the optics in the TSA 120 are much better and the TSA 120 bests the C8 on the planets.
3. The TSA 120 is the better solar white light and Ha telescope.
4. Although the C8 is more compact, both the C8 and the TSA 120 use the same mounts – so there is no portability advantage to the C8.

For the moment, I'm lucky to have both.

Bob

That’s exactly my experience too. My C8 was an Edge, in an attempt to get a slightly sharper SCT, but frankly resolved nowhere near the detail that my TSA can.

[Procyon]

Are you Gasp a collector of tubes ? I have a friend who admitted he has 50 of them. TELESCOPITIS DISEASE can be succinctly described as a blind spot in your peripheral vision where you lose sight of how many scopes one actually has.

 

I only have 3 scopes lol. Looks like I'm looking for an excuse to get another huh?

I used to be a planet guy, than I became a Galaxy guy, now Asterisms, Starfields and OC's primarily.

I dunno, I love it when a huge field of stars fills the huge AFOV of my hyperwide eyepieces. 

You just stare and stare in there...

 

What do you want me to get instead? For every other object I have it pretty much covered with an 11" SCT.

I tried APO's, they didn't do much for me at very low power under 50x that the Achros couldn't.

The idea of looking at objects with a 4-6" APO when I have an 11"...meh, must be a pretty sight though for sure.

 

A big Dob?, can't find space for it atm. You find me something else to get. Not sure why I want the Newt 

now anyhow to be honest. Maybe I just wanted a different look.

This does kind of deflate the whole idea though:

 

"One poor aspect of the design is that the secondary obstruction is rather large at 46 mm. The secondary itself is sensibly sized at about 36 mm, but there is an unnecessarily large metal surround to the assembly which must reduce the light grasp and image contrast."

 

So basically, I'll own another 115mm type of scope huh? With an MPCC, that's

about 800$ CDN thrown in the air? 

 

Know of any very fast 60-90mm APOs, under f/5?

I'll be moving in the countryside soon, around SQM 21.5/Bortle 4, so that may

work out better than an 60-90mm from the outer city/suburb or current SQM 18/Bortle 8-9 zone. 

Edited by Procyon, 09 July 2025 - 05:45 PM.

[PKDfan]

I only have 3 scopes lol. Looks like I'm looking for an excuse to get another huh?
I used to be a planet guy, than I became a Galaxy guy, now Asterisms, Starfields and OC's primarily.
I dunno, I love it when a huge field of stars fills the huge AFOV of my hyperwide eyepieces.
You just stare and stare in there...

What do you want me to get instead? For every other object I have it pretty much covered with an 11" SCT.
I tried APO's, they didn't do much for me at very low power under 50x that the Achros couldn't.
The idea of looking at objects with a 4-6" APO when I have an 11"...meh, must be a pretty sight though for sure.

A big Dob?, can't find space for it atm. You find me something else to get. Not sure why I want the Newt
now anyhow to be honest. Maybe I just wanted a different look.
This does kind of deflate the whole idea though:

"One poor aspect of the design is that the secondary obstruction is rather large at 46 mm. The secondary itself is sensibly sized at about 36 mm, but there is an unnecessarily large metal surround to the assembly which must reduce the light grasp and image contrast."

So basically, I'll own another 115mm type of scope huh? With an MPCC, that's
about 800$ CDN thrown in the air?

Know of any very fast 60-90mm APOs, under f/5?
I'll be moving in the countryside soon, around SQM 21.5/Bortle 4, so that may
work out better than an 60-90mm from the outer city/suburb or current SQM 18/Bortle 8-9 zone.

Nope not gonna help you rationalize TELESCOPITIS Tom. Its a unique affliction with the only downsides costs mounts and room and is a lifelong terminal disease.

I say get what your heart is leading you and if thats a Newt with a big obstruction have at it.

The move to darker skies will be a game changer for sure & i hope that happens soon for ya !

Tom your not hearing me when i say a small HIGH quality apo fully solved for CA is going to blow your mind so forget about aperture size and look for HIGH quality Figures instead.

It must not have false colour is the real secret.

The achro and apo worlds simply do not align even at absurdly low powers.

My new 40XW's terrestrial sweeps at a measely 10.1X and limited star gazing is as you well understand the whole meaning of life. The virtuous field full of brilliant pinpoints seemingly the size of a single photon stream is categorically impossible to describe.

The immaculate image beckons to those that seek for it.

Be strong little grasshoper and one will surely find you as thats how the universe operates...it gives to those that LOVE looking at it-- sooo vain it is. Lol.

It found me twice and man oh man what a nightmare of eyepieces and insanity costs as i just counted out 700dollars more for my next additions and still got 2 Brandons to get and a Herschel wedge. Thats another grand. I NEED help !!

So Fair warning the affliction has no known cure.

Stay safe my friend but hiding in the dark WON'T help one little bit.


Lance has a seriously case of EYEPIECEITIS a corrollary syndrome to the main virus; an equally painful condition for the wallets bottom line.




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