54 replies to this topic

[NSP]

I’ve had a Celestron Nexstar 8SE for a little over a year (and have loved it so far), but I was thinking about getting a small refractor with a shorter focal length to complement it. My goals for this refractor would be:

- Be able to visually observe larger objects like open star clusters, the various objects near Scorpius and Sagittarius, etc.
- Be small/portable enough for travel.
- Be compatible with a Lunt Herschel wedge.

After doing some research, I narrowed it down to two candidates: the Astro-Tech AT80ED and the Astro-Tech AT80EDT.

From what I’ve gathered, the differences between these two models is that the AT80EDT is a triplet (so chromatic aberration should be almost non-existent), has a shorter focal length (wider field views), and costs roughly double what the AT80ED costs.

Between these two models, which would you recommend based on what I want to do with the telescope? I suspect the AT80EDT is “better”, though is it better enough to warrant double the price?

Thank you in advance for your thoughts!

[clearwaterdave]

For just visual the ed is a great scope.,I never looked through the edt so I can't comment on it.,but I have the 80mm and the 102mm Ed's and the views are great.,imho.,Good luck.,

[mac57]

It is a personal thing.  I have an 80ED and love it.  I see little color fringing and would not bother spending double.  As I said, it boils down to personal preferences.  In my fast reflector I tolerate coma pretty well and don't use a corrector, while others would HAVE to use one.  Either scope will be a good choice due to their build quality (like a tank).  Mark

[SchoolMaster]

The 80ED equivalent (SVBONY) was my first decent refractor.  I now also have an AT125EDL.  The amount of CA that is tolerable is a totally personal thing.  The only way to really answer your question is for YOU to compare the two, or similar OTA at a club or star party.

 

I'd get a used 80ED and go from there.  Refractors hold value well.  You might decide that an AT72EDII was more suitable for your needs, so starting inexpensive gives you better options.  The lighter 80ED will be easier to mount.

[eyespy]

Hi NSP,

 

The 80mm ED version is excellent with negligible CA and excellent higher power views. With the savings, I would pick up a Lunt Herschel solar wedge and a couple of eyepieces. 80mm is perfect for solar observation especially with an Svbony 3 - 8mm zoom lens. At night, the 80mm ED is a perfect GnG scope and I am surprised at how well it performs compared to my 102mm EDL.

 

Doug…..

Edited by eyespy, 03 June 2023 - 10:04 AM.

[truckerfromaustin]

I'm going to recommend waiting until a good, used at80edl shows up in the classifieds section of CN. It's an excellent scope for wide angle, low power use and it can be used at 200x magnification for the planets. It's a very good grab and go scope that is difficult to beat for its optical quality.

CS, Greg

[russell23]

For the visual deep sky targets you mentioned either should be fine.  The EDT will have more field curvature.  Depending upon your eyepieces you may get better edge performance with the ED than the EDT.

 

OTOH, the EDT will have a heavier objective end which can help with OTA balance when using a 2” star diagonal and a heavier eyepiece. 

 

As noted, the ED will have some visible CA, but for the deep sky targets this should not be a major issue.  I had the 102mm f/7 ED and the CA, while visible, was not problematic with that scope for deep sky.

[wrvond]

I’ve had a Celestron Nexstar 8SE for a little over a year (and have loved it so far), but I was thinking about getting a small refractor with a shorter focal length to complement it. My goals for this refractor would be:

- Be able to visually observe larger objects like open star clusters, the various objects near Scorpius and Sagittarius, etc.
- Be small/portable enough for travel.
- Be compatible with a Lunt Herschel wedge.

After doing some research, I narrowed it down to two candidates: the Astro-Tech AT80ED and the Astro-Tech AT80EDT.

From what I’ve gathered, the differences between these two models is that the AT80EDT is a triplet (so chromatic aberration should be almost non-existent), has a shorter focal length (wider field views), and costs roughly double what the AT80ED costs.

Between these two models, which would you recommend based on what I want to do with the telescope? I suspect the AT80EDT is “better”, though is it better enough to warrant double the price?

Thank you in advance for your thoughts!

Neither. AT80EDL. 

[SchoolMaster]

Neither. AT80EDL. 

Used.  I thought Astronomics have discontinued the new ones.

[truckerfromaustin]

Used. I thought Astronomics have discontinued the new ones.

The 80edl has been discontinued, but the 102 and 125 will still be available.

Greg

[wrvond]

Used.  I thought Astronomics have discontinued the new ones.

You’re right, I forgot. 

[Jon Isaacs]

Both are good scopes.. It's hard to go wrong with either one.. 

 

Jon

[topomountain]

of course the 80edt will have a little wider max fov and be a little more compact as well

[Doug Culbertson]

The AT80EDT is actually a good bit shorter than the AT80ED or the AT80EDL. I can store the AT80EDT in an Apache 4800 case with room for a couple of eyepieces and a 1.25" diagonal; I couldn't do that with the EDL. I have owned all three of these AT 80mm scopes and all were quite good in their own way. Yes, on bright objects the ED will show a bit of CA but, as has been pointed out, it's not obtrusive at all. 

 

I ended up selling my AT80EDL to purchase the AT80EDT for a couple of reasons, not least of which is the faster focal ratio so I could get closer to full disk views of the sun using a Daystar Quark. It does accomplish that but, in the end, I may end up selling the EDT as well because, frankly, aperure rules for solar and I much prefer using my AT102EDL. It's the sweet spot for Ha solar, IMO. 

 

But, the AT80EDT is quite a compact telescope, even with the dew shield extended. 

 

 

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[Moondust]

Get the 80ED and you'll likely be selling and upgrading once the honeymoon phase wears off. With the 80EDT you have a lifetime scope. I'd get a new 80EDT over a used 80EDL because personally I've had better luck with QC with my two EDT's (80 and 115) over my two EDL's (102) which were both returned. Perhaps my EDT's were made precovid when QC was a little tighter or I just got unlucky who knows. Plus the EDT's come with a nice hard shell case and a classy looking gold fine focus knob, not the plain looking silver one as on all the EDL's. 

[TNmike]

I don't find my AT80EDT to be front heavy, surprisingly.

[robjme]

I purchased an AT80 EDT a few months ago. I am very happy with its performance.

I am a moderately skilled observer and really not qualified to give a thorough, detailed review, but I do have some opinions to share.

I bought this scope as a grab-n-go. I have larger scopes. It is compact and weighs less than my eyepiece case. My wife says it looks cute. What more do you need to know?

The views are impressive. The stars are pinpoints and the craters on the moon are so sharp. Speaking of the moon, I burned my eye looking at a full moon for fifteen minutes or more last night. I could see a minute green line at the moon's edge, but it was minimal while the view of the moon was phenomenal.

Telescopes need to be balanced, or they will not cooperate. On first light, I mounted a 2" diagonal with a TV 40mm, and my CG-4 mount struggled to keep up. I immediately ordered a Losmandy 11" dovetail plate and 2.5 lb. counterweight. Now the scope behaves and is a joy.

Edited by robjme, 03 June 2023 - 11:55 AM.

[wrvond]

I purchased an AT80 EDT a few months ago. I am very happy with its performance.

I am a moderately skilled observer and really not qualified to give a thorough, detailed review, but I do have some opinions to share.

I bought this scope as a grab-n-go. I have larger scopes. It is compact and weighs less than my eyepiece case. My wife says it looks cute. What more do you need to know?

The views are impressive. The stars are pinpoints and the craters on the moon are so sharp. Speaking of the moon, I burned my eye looking at a full moon for fifteen minutes or more last night. I could see a minute green line at the moon's edge, but it was minimal while the view of the moon was phenomenal.

Telescopes need to be balanced, or they will not cooperate. On first light, I mounted a 2" diagonal with a TV 40mm, and my CG-4 mount struggled to keep up. I immediately ordered a Losmandy 11" dovetail plate and 2.5 lb. counterweight. Now the scope behaves and is a joy.

My wife awards a cuteness value to my scopes as well. She thought the blue and white Meade R5 was so cute she claimed it as her own and gave it pride of place in her home office!

[CHASLX200]

My AT80ED takes 400x and keeps going.

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[stevew]

If your planning astrophotography go with the triplet.

If it's just for visual, as a wide field scope, or grab and go then stick with the regular AT80 ED.

I purchased one this year and it is very well corrected. I think you will be pleased with it.

[clearwaterdave]

My AT80ED doing so daytime work spying on the birdies and Venus.,an Luna too.,

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[sevenofnine]

+1 on stevew's post. It clear and concise. The triplet is a little faster scope at f/6 with an extra element to eliminate CA for AP. The standard doublet is slower at f/7 and it will show a little CA. I really like my AT80ED. It's a great little refractor for visual astronomy 

Edited by sevenofnine, 03 June 2023 - 08:14 PM.

[Oldfracguy]

I just bought a BST 2.5mm 58° AFOV Planetary Eyepiece to use with a second-hand AT80ED I picked up a couple weeks ago.  That will let me hit 224x on the Moon and double stars.  I just came in from using a much longer focal length eyepiece, an Orion 15mm UFF, to watch hummingbirds load up at the feeder before dark.

 

I've had my share of these 80mm ED refactors, and if you prize the most crisp, sharpest, most detailed images possible with the two very fine Astro-Tech scope you mention, and if the extra few hundred $$$ does not pose a problem, go straight for the AT80EDT.  Even though it has a shorther focal length, and therefore provides a slightly wider field of view with the same eyepieces as the AT80ED will, it will take higher magnification better.  You will be able to see smaller details on the Moon, the planets, and you won't see any bluish fringing around bright objects like Venus, which is now at it brighest and closest to us in its crescent phase. Everythng you see will be crisper and appear more in focus with the AT80EDT.  DSO targets will be about the same in both scopes.  Several days ago I was able to use this AT80ED with a 2" 30mm 70° AFOV eyepiece and an O-III filter to view the entire Veil Nebula.  The AT80EDL will do that in its sleep.

 

It really just boils down to how much you want to spend.  Both scopes are great performers, but if you can swing it, go for the AT80EDT.  It fits very nicely in the hard case that comes with it, too.

Edited by Oldfracguy, 03 June 2023 - 10:44 PM.

[Jon Isaacs]

My two cents:

 

It is a complicated question.. Looking at the Astro-Tech refractor page, I'm not seeing the AT-80EDT.

 

- For high power sharpness in an 80 mm, the 80 mm EDL would be my choice. For widest field views with very good views, the 80 mm EDT.

 

The best view for the money, the 80 mm ED or the 102 mm ED.  The AT-80ED gives up a little to it's better corrected siblings in terms of color correction but the views are still very good. The AT-102ED is not a well corrected for color as the EDT or the EDL but it more than makes up for it with it's larger aperture.

 

Jon

[russell23]

My two cents:

 

It is a complicated question.. Looking at the Astro-Tech refractor page, I'm not seeing the AT-80EDT.

 

- For high power sharpness in an 80 mm, the 80 mm EDL would be my choice. For widest field views with very good views, the 80 mm EDT.

 

The best view for the money, the 80 mm ED or the 102 mm ED.  The AT-80ED gives up a little to it's better corrected siblings in terms of color correction but the views are still very good. The AT-102ED is not a well corrected for color as the EDT or the EDL but it more than makes up for it with it's larger aperture.

 

Jon

That price for the 80mm ED is really hard to beat.  If you are just getting into the refractor world you can't do any better than that.  I'm tempted to get one just to have for its ultra-portability.