119 replies to this topic

[Joe Bergeron]

 

Another thing that caught my eye is the schematics that Askar posts for this particular model. They show an OTA diameter of 110mm. So, if I'm looking at it correctly, they are sticking a 120mm diameter objective on a 110mm tube. Obviously I am no optical expert, but wouldn't this cut down on the effective aperture right off the bat? Maybe I'm not as enamored with this scope as I was when I got the email from Agena. 

I just received one of these and I performed the flashlight test. It operates at full aperture. 

[chvvkumar]

Review from Narrowband channel:

 

https://www.youtube....h?v=UUVMiClk3Ag

[Oldfracguy]

After submitting a 3-star review of the 120 on the Agena website, I received a message from them.  Apparently, Askar has a fix for problematic focusers.  So, if anybody has one of these 103 or 120 scopes that has or develops focuser problems, Askar may have a solution:

 

https://agenaastro.c...-telescope.html

Edited by Oldfracguy, 01 March 2024 - 12:15 PM.

[Joe Bergeron]

I removed the orange dovetail bar from my 120 and replaced it with an Astro-Physics one I had lying around. Why? Some of my mounts would have torn up that orange bar. If I ever wanted to sell the scope, those dings would prejudice customer satisfaction. 

[Oldfracguy]

I removed the orange dovetail bar from my 120 and replaced it with an Astro-Physics one I had lying around. Why? Some of my mounts would have torn up that orange bar. If I ever wanted to sell the scope, those dings would prejudice customer satisfaction. 

I did the same thing on the 120 I had   .  I always use my old "beater" Celestron solid aluminum dovetail rail and save the stock dovetail rail for that very reason:

 

 

I also moved those two screws on the small guide scope dovetail rail to the ends so I could use that as a handle.  It works great for that.

Edited by Oldfracguy, 02 March 2024 - 12:00 AM.

[SoCal Brian]

After submitting a 3-star review of the 120 on the Agena website, I received a message from them.  Apparently, Askar has a fix for problematic focusers.  So, if anybody has one of these 103 or 120 scopes that has or develops focuser problems, Askar may have a solution:

 

https://agenaastro.c...-telescope.html

I just read your review on the Agena website. In it you conclude that "the AT115EDT is a far better scope all around", despite your only complaint about the Askar being the focuser problem you experienced. And you had stated in the same review that "Optically, the Askar 120 APO is the equal or better than the AT115EDT". So were there other issues with the Askar that you experienced that make the AT115EDT a far better scope all around? Or was it just the focuser issue? If you had not had the focuser problem would you still have had the same conclusion? Thanks.

[RichA]

I removed the orange dovetail bar from my 120 and replaced it with an Astro-Physics one I had lying around. Why? Some of my mounts would have torn up that orange bar. If I ever wanted to sell the scope, those dings would prejudice customer satisfaction. 

That's the annoying thing;  it holds as much sway in some people's minds as the functionality of the scope when sold.

I'm not saying a dinged up tube should be welcomed, but a $25.00 Vixen bar?  I'd just replace it.

[Oldfracguy]

I just read your review on the Agena website. In it you conclude that "the AT115EDT is a far better scope all around", despite your only complaint about the Askar being the focuser problem you experienced. And you had stated in the same review that "Optically, the Askar 120 APO is the equal or better than the AT115EDT". So were there other issues with the Askar that you experienced that make the AT115EDT a far better scope all around? Or was it just the focuser issue? If you had not had the focuser problem would you still have had the same conclusion? Thanks.

I think I would have, actually.  But remember, I just do visual observation, and don't use a binoviewer.  The Askar 120 APO has a removable section at the end of the tube to accomodate a binoviewer, and comes with features geared toward imaging that the AT115EDT does not come with, like a guide scope dovetail mounting bar that also serves as a handle.  What the AT115EDT has that the Askar 120 APO does not is a fully rotating focuser assembly.  The large thumbscrew (orange arrow in photo below) can be backed off and the entire focuser assembly--finder scope, focus knob axis, diagonal--rotates together as a unit.  That is a really useful feature if you use a GEM mount:

 

 

 

 

The Askar APO 120 only comes with a camera angle adjuster, and a nice one at that, at the end of the drawtube.  That AT115EDT also has one as well that is operated by a different thumbscrew  (yellow arrow in photo):

 

 

 

 

The feature I value the most probably about the AT115EDT is that is has a fully collimatable objective cell.  Behind the silver collar at the back of the sliding dew shield are three pairs of "push-pull" collimation screws that adjust the "tilt" of the objective cell relative to the axis of the telescope tube itself:

 

 

 

 

If, for some reason, the threads on either the focuser, the objective cell, or one or both ends of the tube have not been turned perfectly square with the tube, the result will be a scope that is not in perfect collimation.  It is wonderful to have a way to fix that issue should it be present.  I did have to avail myself of the AT115EEDT's collimation capability with a used one I bought from a CN member who had used it for imaging.  After a few adjustments that scope put up perfectly circular, concentric and well-separated diffraction rings.

 

The other issue I had with the Askar 120 APO is that it needed an extension tube (yellow arrow in photo below) to reach focus using a good Baader T2 Zeiss Prism Diagonal:

 

 

 

 

I could reach focus with all my diagonals (2" Mirror, T2 Prism, 45° Erect Image Prism) on the AT115EDT without having to use any extension tubes.

Edited by Oldfracguy, 02 March 2024 - 11:22 AM.

[Oldfracguy]

In fact, one afternoon after I had set the AT115EDT outside to get ready for the night's observing, I spotted a target at fairly close range, perhaps only 40 feet away.  I inserted the 2" mirror diagonal and a basic 9mm Plossl with no extension tube needed:

 

 

 

and was able to capture this, the extent of my "imaging" :

 

 

 

 

 

 

[SoCal Brian]

I think I would have, actually.  But remember, I just do visual observation, and don't use a binoviewer.  The Askar 120 APO has a removable section at the end of the tube to accomodate a binoviewer, and comes with features geared toward imaging that the AT115EDT does not come with, like a guide scope dovetail mounting bar that also serves as a handle.  What the AT115EDT has that the Askar 120 APO does not is a fully rotating focuser assembly.  The large thumbscrew (orange arrow in photo below) can be backed off and the entire focuser assembly--finder scope, focus knob axis, diagonal--rotates together as a unit.  That is a really useful feature if you use a GEM mount:

 

 

101_2528_(2).JPG

 

 

The Askar APO 120 only comes with a camera angle adjuster, and a nice one at that, at the end of the drawtube.  That AT115EDT also has one as well that is operated by a different thumbscrew  (yellow arrow in photo):

 

 

101_2527_(2).JPG

 

 

The feature I value the most probably about the AT115EDT is that is has a fully collimatable objective cell.  Behind the silver collar at the back of the sliding dew shield are three pairs of "push-pull" collimation screws that adjust the "tilt" of the objective cell relative to the axis of the telescope tube itself:

 

 

101_1903.JPG

 

 

If, for some reason, the threads on either the focuser, the objective cell, or one or both ends of the tube have not been turned perfectly square with the tube, the result will be a scope that is not in perfect collimation.  It is wonderful to have a way to fix that issue should it be present.  I did have to avail myself of the AT115EEDT's collimation capability with a used one I bought from a CN member who had used it for imaging.  After a few adjustments that scope put up perfectly circular, concentric and well-separated diffraction rings.

 

The other issue I had with the Askar 120 APO is that it needed an extension tube (yellow arrow in photo below) to reach focus using a good Baader T2 Zeiss Prism Diagonal:

 

 

101_2725_2.JPG

 

 

I could reach focus with all my diagonals (2" Mirror, T2 Prism, 45° Erect Image Prism) on the AT115EDT without having to use any extension tubes.

Thank you for the detailed response!

[rayden68]

I doubt Askar will reveal glass type they using...

I keep noticing people mentioning that Askar will not tell what glass they are using. Now some just want to know out of curiosity but some are using it as a smear like they are doing something underhanded? So what glass was used in the AP Super Planetary telescope and some of the other AP scopes from that time period???? The slang named mystery "NASA" glass?

[Daniel Mounsey]

Most reviews in the past were done with little disclosure on glass because they were based on real observations. Today, it's just the opposite. Few are even observing and instead, basing their discussions on glass types and color curves but most really have no idea how the refractors actually perform visually. It's very obvious that most are struggling to translate their findings into reality because they literally have so little if any experience with observing. Analysis paralysis. 

Edited by Daniel Mounsey, 03 March 2024 - 05:19 PM.

[PKDfan]

Most reviews in the past were done with little disclosure on glass because they were based on real observations. Today, it's just the opposite. Few are even observing and instead, basing their discussions on glass types and color curves but most really have no idea how the the refractors actually perform visually. It's very obvious that most are struggling to translate their findings into reality because they literally have so little if any experience with observing. Analysis paralysis.

Will we be talking about the same talk a decade from now Daniel ? ?

ABSOLUTELY !!

And
Its a crime.

CS

[Daniel Mounsey]

Times change, but observation doesn't change if one actually observes. 

[Joe Bergeron]

I will absolutely evaluate my scope visually as soon as I get a chance. Could be a while…

[CHASLX200]

Don't give a hoot about glass. Give me Jup in dead still seeing at 350x in that 120 i can tell what is up fast.

[Joe Bergeron]

I was able to do a preliminary evaluation of my 120 last night. I say “preliminary” because the seeing was fair at best. I glimpsed reasonable ruffly detail on the equatorial belts on Jupiter at 240x, and no spurious color other than atmospheric dispersion, but the image was jumping and quivering too much for much more. Star tests were satisfactory, no sign of astigmatism, similar but not identical on either side of focus, very clearly defined rings inside of focus, somewhat more blurry outside. 
 

in focus, stars were intense, tiny points surrounded by a neat, faint diffraction ring (Aldebaran). Sirius was a mess due to seeing, but it showed no color error that I could detect. 
 

For what it’s worth, I had a lovely view of M42 at 56x. I was too cold to do any more. 
 

I had no trouble with the focuser slipping. The scope rode well on my SkyView Pro mount. 

Attached Thumbnails

• 

[Oldfracguy]

I was able to do a preliminary evaluation of my 120 last night. I say “preliminary” because the seeing was fair at best. I glimpsed reasonable ruffly detail on the equatorial belts on Jupiter at 240x, and no spurious color other than atmospheric dispersion, but the image was jumping and quivering too much for much more. Star tests were satisfactory, no sign of astigmatism, similar but not identical on either side of focus, very clearly defined rings inside of focus, somewhat more blurry outside. 
 

in focus, stars were intense, tiny points surrounded by a neat, faint diffraction ring (Aldebaran). Sirius was a mess due to seeing, but it showed no color error that I could detect. 
 

For what it’s worth, I had a lovely view of M42 at 56x. I was too cold to do any more. 
 

I had no trouble with the focuser slipping. The scope rode well on my SkyView Pro mount. 

Nice review, Joe.  According to Agena, Askar has a fix if that focuser ever develops slippage.  Hopefully it won't.  I did notice on my Askar 120 APO that even in fairly mild Southern California it took a half hour at least to stabilize going from a garage to outside, with a temperature difference of only about 15-20 degF max.  I just pointed the scope at some stars and focused after I first set it up.  I kept going back outside every few minutes and re-adjusting the focuser slightly.  When I no longer had to re-adjust the focuser, I knew the scope was ready for business.  I also checked the collimation of mine using a Cheshire for Refractors, and it was spot on.  Same as you, I saw an essentially textbook diffraction pattern when star testing using a 7mm Orthoscopic eyepiece and defocusing slight inward, with only slightly less perfect, but still well-separated, diffraction rings when defocusing outward slightly.  Whatever ED glass Askar is using, and how they have figured the three lens elements, they have a winning combination.  These scopes are quite good optically, no question about that.

Edited by Oldfracguy, 08 March 2024 - 12:50 PM.

[Joe Bergeron]

My focuser did slip like crazy at first.  I found that the adjustment screw was not engaged at all. Tightening it a wee bit removed the slipping. I will be curious to see if Askar has some other suggestion. 
 

By the way, it would be hard to mistake that little screw for any other, because the other three openings in that row are just threaded holes for installing an electronic focuser. 
 

I also checked collimation with a Cheshire and found it was perfect. 

[Brollen]

Bumping this thread … Hey Joe wondering if you had any updates to report out regarding the 120?

 

Clear skies!

[Joe Bergeron]

Nope, not yet. 

[ngc891]

For people using this scope with an EAF, it is possible to fit it back in the case with an attached EAF (cutting some foam)?

The case seems narrow and mounting/unmounting the EAF everytime moving the scope is not fun...

[Oldfracguy]

For people using this scope with an EAF, it is possible to fit it back in the case with an attached EAF (cutting some foam)?

The case seems narrow and mounting/unmounting the EAF everytime moving the scope is not fun...

I just stash those hard cases and use an Orion padded bag to store larger refractors, and to take them in the car out to dark sky locations.  You can probably leave the guide scope in place even with one of these padded carry bags, let alone your EAF.  Here's my old Askar 120 APO in the Orion soft padded carry bag:

 

 

 

 

[Joe Bergeron]

I have a slight bit more to report about this scope. I brought it out to a darkish site on a clear but somewhat murky, unimpressive night with fair seeing. I looked at a few doubles (Izar, Porrima, Algieba), nothing very difficult, but six pretty star images nonetheless. M3 showed reasonable resolution for the conditions at 120x. The galaxies M104 and M51 were faint, but a little patience and averted vision increased their extent and showed their basic shapes. It star tested nicely. I have no complaints, it’s clearly a competent telescope of its aperture. 

Attached Thumbnails

• 

[ris242]

A good review if anyone is interested.

(sounds like he got a good focuser lol).

 

https://www.youtube....h?v=ni5XiYPTUOo