57 replies to this topic

[BRCoz]

Enjoy the scope you get.  

[TNmike]

Astronomics is showing the AT80EDT in stock:

 

https://www.astronom...ractor-ota.html

[mourip]

My two cents:

 

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

For some reason it does not show up with the other AT scopes but here it is...

 

https://www.astronom...ractor-ota.html

 

Oddly the 80 EDL still does show up but is no longer available.

 

I am hovering over either the 80EDT or the 90CFT

[gwlee]

I only use telescopes visually, and I have never used an AT80EDT. I had an AT80 here for a few weeks testing it, and putting it on one of my mount/tripod combinations before giving it to a friend. It’s a good, inexpensive scope, but I think I would prefer the AT80EDT for travel because it’s shorter.

 

The AT80 (f7) is as long as my 92mm AP Stowaway, which is a bit too long to suit me for travel, and I can’t store it fully assembled where I want to store it at home.  Based on its published specs, the AT80EDT would fit.

 

Even though it’s about twice as expensive, and I wouldn’t use it for photography, I would chose the shorter scope because it meets all my portability requirements, so I suggest carefully determining YOUR portability requirements, and then buying the scope that best fits them. 

Edited by gwlee, 04 June 2023 - 07:44 PM.

[gwlee]

My two cents:

 

 Looking at the Astro-Tech refractor page, I'm not seeing the AT-80EDT.

That’s a long standing problem with the Astronomics website. If you search all non-computerized refractors the AT80EDT shows up, but it doesn’t show up if you search under Astronomics refractors. 

[TNmike]

I found it under Telescopes/By Manufacturer/Astro-Tech, then Astro-Tech EDT Refractors.

[Oldfracguy]

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.

 

After considering these criteria, the AT80ED will be fine.  Here's one with a Herschel Wedge, courtesy of another CN member who sent me this photo after he bought the first AT80ED I had:

 

Edited by Oldfracguy, 04 June 2023 - 09:53 PM.

[Jon Isaacs]

For some reason it does not show up with the other AT scopes but here it is...

 

https://www.astronom...ractor-ota.html

 

Oddly the 80 EDL still does show up but is no longer available.

 

I am hovering over either the 80EDT or the 90CFT

 

That is a difficult choice, quite a difference in cost.  I have two older scopes, an Astro-Tech 80 LE.  It's a carbon fiber 80mm F/6 FPL-53 doublet. 80mm F/6 FPL-53 doublets are quite rare but should have color correction similar to a PK-61 triplet.  It is a compact scope, I love the wide field views, 5.5 degrees with the 41mm Panoptic, 5.0 degrees with the 31mm Nagler.  And it does a good job at higher mags on the planets and double stars.  

 

I also have a William Optics Megrez 90 FD.  This is a 90mm F/6.2 FPL-53 Doublet that is about the size of the 80mm F/6 and not much heavier.  The color correction is not on the same level as the 90mm CFT but it is quite good and for visual purposes plenty good enough.

 

The two scopes side by side.  The 90mm is only slightly longer than the 80mm and weighs less than one pound more. 

 

 

What makes the choice difficult is that while the difference between an 80mm and a 90mm is not that much, with the 90mm you are getting nearly the performance of 4 inch but in a scope that is not much, if any, heavier or larger than an 80mm.  

 

This photo shows the difference between the 90mm F/5.5 Svbony 48P which is about the size of the 80mm F/6 and the NP-101.. 

 

 

Jon

Edited by Jon Isaacs, 05 June 2023 - 04:28 AM.

[Wildetelescope]

For visual, I would expect the 80 ED and 80 EDT I would expect the EDT to behave slightly better.  80 EDL and EDT would be pretty close.   My 80 EDT showed only the very slightest color around the Airy disk on Sirius at 170X. And since it was red on one side and Blue on the other, I suspect that was Atmospheric dispersion.  For imaging, you can check out the 80 EDT folder in my gallery to see examples of what I have done with that scope.  Again, I would expect its performance to be comparable with the 80 EDL.   I would expect the AT 80 ED to show a bit more CA to the camera, but even that should be manageable with processing.  Any of the scopes would be a good value for their price point.

 

Cheers!

 

JMD

[topomountain]

What you did not mention is from the eyepiece...

the at 80 le be the wo 90fd how do they compare?

 

i have the Orion 80ed f 6.25 fpl53 probly simmilar to the at80le

 

That is a difficult choice, quite a difference in cost.  I have two older scopes, an Astro-Tech 80 LE.  It's a carbon fiber 80mm F/6 FPL-53 doublet. 80mm F/6 FPL-53 doublets are quite rare but should have color correction similar to a PK-61 triplet.  It is a compact scope, I love the wide field views, 5.5 degrees with the 41mm Panoptic, 5.0 degrees with the 31mm Nagler.  And it does a good job at higher mags on the planets and double stars.  

 

I also have a William Optics Megrez 90 FD.  This is a 90mm F/6.2 FPL-53 Doublet that is about the size of the 80mm F/6 and not much heavier.  The color correction is not on the same level as the 90mm CFT but it is quite good and for visual purposes plenty good enough.

 

The two scopes side by side.  The 90mm is only slightly longer than the 80mm and weighs less than one pound more. 

 

 

 

What makes the choice difficult is that while the difference between an 80mm and a 90mm is not that much, with the 90mm you are getting nearly the performance of 4 inch but in a scope that is not much, if any, heavier or larger than an 80mm.  

 

This photo shows the difference between the 90mm F/5.5 Svbony 48P which is about the size of the 80mm F/6 and the NP-101.. 

 

 

 

Jon

 

[mrsjeff]

I found it under Telescopes/By Manufacturer/Astro-Tech, then Astro-Tech EDT Refractors.

Similarly, I go to telescopes/by manufacturer/Astro-Tech, then Telescope Type/Refractor Telescopes. Then I can see all the ones I'd like to get. 

[Jon Isaacs]

What you did not mention is from the eyepiece...

the at 80 le be the wo 90fd how do they compare?

 

i have the Orion 80ed f 6.25 fpl53 probly simmilar to the at80le

 

As I mentioned, the differences are not great.  The 80mm F/6 provides a wider field of view, the 90mm F/6.2 goes a little deeper, has somewhat better resolution.  It is about halfway between a 80mm and a 4 inch in terms of performance.  I am a double star guy so the resolving power advantage is helpful.  

 

These two scope come under the category of "more alike than different."  I like the wider fields of the 80mm under dark skies and the high power capabilities of the 90mm under bright skies..  For most observers, either one is probably fine.  I just like small, quality refractors.

 

Jon

Edited by Jon Isaacs, 06 June 2023 - 09:23 AM.

[NSP]

Sorry for the post-and-ghost, and thank you for the input! After further consideration, I ended up getting the AT80EDT. After using it for four nights, I can say that I really enjoy it! Some neat things I’ve done with it so far include:

- Seeing the Eagle Nebula (M16) and the Omega Nebula (M17) in the same field of view.
- Scanning around the Milky Way between Sagittarius and Scorpius.
- Seeing the Moon/Mars conjunction in the same field of view about 2 weeks ago.
- Seeing all three components of Iota Cassiopeia at 160x. This is the maximum useful magnification for an 80mm telescope, and it certainly wasn’t a clean split, but all three stars were distinct.
- Watching airplanes fly through the field of view is fun!
- Looking at the moon with the clouds blowing in front of it last night was a remarkable sight to behold. It almost didn’t seem real!

So, the AT80EDT is a great complement to my 8” SCT, and should serve me well for years to come.

[Wildetelescope]

Sorry for the post-and-ghost, and thank you for the input! After further consideration, I ended up getting the AT80EDT. After using it for four nights, I can say that I really enjoy it! Some neat things I’ve done with it so far include:

- Seeing the Eagle Nebula (M16) and the Omega Nebula (M17) in the same field of view.
- Scanning around the Milky Way between Sagittarius and Scorpius.
- Seeing the Moon/Mars conjunction in the same field of view about 2 weeks ago.
- Seeing all three components of Iota Cassiopeia at 160x. This is the maximum useful magnification for an 80mm telescope, and it certainly wasn’t a clean split, but all three stars were distinct.
- Watching airplanes fly through the field of view is fun!
- Looking at the moon with the clouds blowing in front of it last night was a remarkable sight to behold. It almost didn’t seem real!

So, the AT80EDT is a great complement to my 8” SCT, and should serve me well for years to come.

the EDT is a great scope and it is small enough to do a lot of terrestrial viewing too!   Have fun!

 

JMD

[davelpg]

I've read mention of the AT80EDT being "wider" than the AT80ED.  Can I ask how much "wider" and how is this determined?  

Edited by davelpg, 31 August 2023 - 10:37 AM.

[wrvond]

The True Field of View (TFoV) varies with the eyepiece selected. Here is an example of each scope using a Nagler 13mm Type 6:

 

 

Both scopes are 80mm aperture but the ED is f/7 and the EDT is f/6, which results in a different focal length. 

Edited by wrvond, 31 August 2023 - 11:24 AM.

[Regulus 1.36]

I have the AT 80ED, and it's a great scope that most would think costs a lot more than it does.

 

I took these images of the moon yesterday with my cell phone handheld through an ES 24 mm and ES 4.5 mm eyepieces.

 

The only photoshopping I did was to reduce brightness and increase contrast, similar to using a variable ND filter, if I owned one. LOL

 

P.S. The images are sharper, but I have to reduce the image resolution in order to post them here. Also there is a little CA however, I believe that it's caused by my cell phone camera lens. 

Attached Thumbnails

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Edited by Regulus 1.36, 03 September 2023 - 05:00 AM.

[Wildetelescope]

Those are excellent hand held images!  You have steadier hands than I:-).  

 

JMD

[stevew]

Great shots!

[Estel11]

I have had my AT80ED for some time now. I use it as a grab-and-go companion to my AT125EDL. I am very happy with how it performs, both as a low power and planetary scope. It handles high power very well, not all that much false color. Compared to a Stellarvue acromat I used to own, or an old Pronto, it's much better in that regard. The moon shows a small amount on the edges, jupiter shows very little at all. For me, it's a non-issue. The AT125EDL shows none at all, unless you really, really look for it. For the money you pay for it, the AT80ED is outstanding. I have mine mounted on an old Telepod. It works very well. I think most observers would be happy with it. I have never looked through an AT80EDL, but I did have the AT102EDL for a while. Yes, I do think the EDL versions are noticeable better, but my little 80ED is very nice. I stupidly thought about selling it a while back, but fortunately changed my mind. If an 80mm was my only scope, I likely would choose the AT80EDL. As it is, the 80ED is easily good enough for what I need. The AT80EDT I have not had the chance to observe with. I would love to see how it matches up to the EDL doublet.

Edited by Estel11, 12 September 2023 - 01:27 PM.

[Oldfracguy]

I have had my AT80ED for some time now. I use it as a grab-and-go companion to my AT125EDL. I am very happy with how it performs, both as a low power and planetary scope. It handles high power very well, not all that much false color. Compared to a Stellarvue acromat I used to own, or an old Pronto, it's much better in that regard. The moon shows a small amount on the edges, jupiter shows very little at all. For me, it's a non-issue. The AT125EDL shows none at all, unless you really, really look for it. For the money you pay for it, the AT80ED is outstanding. I have mine mounted on an old Telepod. It works very well. I think most observers would be happy with it. I have never looked through an AT80EDL, but I did have the AT102EDL for a while. Yes, I do think the EDL versions are noticeable better, but my little 80ED is very nice. I stupidly thought about selling it a while back, but fortunately changed my mind. If an 80mm was my only scope, I likely would choose the AT80EDL. As it is, the 80ED is easily good enough for what I need. The AT80EDT I have not had the chance to observe with. I would love to see how it matches up to the EDL doublet.

You will be able to hit higher magnifications with the EDL version and still maintain a sharp image.  You will see practically zero color, even on Sirius, using a mirror diagonal, but a little color using a prism diagonal with the EDL version, whereas the ED will show lots of bluish fringing, even with a mirror diagonal.  The other thing I have noticed between the ED and EDL versions is that the images you see during the day for terrestrial viewing (e.g., birdwatching, etc.) are much better with the EDL version.

[Estel11]

I do not doubt that the EDL is more color free, and a bit sharper, compared to the ED. The ED is still very good. The comparison I was more curious about, with both the 80mm scopes and the larger versions, was between the EDT triplet scopes and the EDL doublets. I'm pretty sure it would be a close call. From what I have read, the Astro-Tech triplets are very nice.

[truckerfromaustin]

I do not doubt that the EDL is more color free, and a bit sharper, compared to the ED. The ED is still very good. The comparison I was more curious about, with both the 80mm scopes and the larger versions, was between the EDT triplet scopes and the EDL doublets. I'm pretty sure it would be a close call. From what I have read, the Astro-Tech triplets are very nice.

I've done a head to head comparison between the edl and the edt. The edl had slightly better color correction and better contrast, but the edt seemed to show more detail on the moon. At 200x magnification the edl was better on the planets, but by a small percentage. Both scopes are excellent for low power, wide angle observation.My seeing conditions were not good with partly cloudy skies and high humidity levels. Overall, I would say that it was a draw between them. A close friend of mine did the same comparison between the scopes and preferred the edl for visual use. He's keeping both of them. The edl is for visual use and the edt will be used for astrophotography. You can't go wrong with either scope though.
Just my 2 cents.

Clear Skies,
Greg

Edited by truckerfromaustin, 13 September 2023 - 11:52 AM.

[Oldfracguy]

I do not doubt that the EDL is more color free, and a bit sharper, compared to the ED. The ED is still very good. The comparison I was more curious about, with both the 80mm scopes and the larger versions, was between the EDT triplet scopes and the EDL doublets. I'm pretty sure it would be a close call. From what I have read, the Astro-Tech triplets are very nice.

Sorry, I forgot to include my experience with an 80mm f/6 "EDT"-type triplet, and it parallels what others have reported.

 

Earlier this year I wanted to see how one of these 80mm ED triplets would compare to an "EDL"-type 80mm Doublet, and I found a very slightly used SvBONY SV550 80mm f/6 ED Triplet:

 

 

This scope has an FPL-51 center element, which is the optical equivalent of the "regular ED" glass used in the AT80EDT and the other ATxxxEDT scopes.  The views were sharp, but the thing I noticed most about the f/6 triplet was the increased Field Curvature I could definitely see.  I wasn't using a flattener such as a TSFLAT2, and the Field Curvature really makes its presence known.  The other thing was that this scope had less focuser travel than the 80mm f/7 ED Doublets, and I needed an extension tube for some daytime terrestrial viewing at fairly close range.  All of those observations pertain to visual use, and I would have to conclude that the AT80EDL, or its clones that are still available like the TS-Optics 80mm f/7 FPL-53 Doublet:

 

 

or the William Optics Zenithstar 81 81mm f/6.9 FPL-53 Doublet:

 

 

would be preferred for visual observation.

Edited by Oldfracguy, 13 September 2023 - 04:43 PM.

[stevew]

" The views were sharp, but the thing I noticed most about the f/6 triplet was the increased Field Curvature I could definitely see.  I wasn't using a flattener such as a TSFLAT2, and the Field Curvature really makes its presence known.  The other thing was that this scope had less focuser travel than the 80mm f/7 ED Doublets, and I needed an extension tube for some daytime terrestrial viewing at fairly close range.  All of those observations pertain to visual use, and I would have to conclude that the AT80EDL, or its clones that are still available like the TS-Optics 80mm f/7 FPL-53 Doublet:"

 

 

 

Make sense to me..