User Experiences ASKAR 120 APO Askar 120APO · Niels_L · ... · 59 · 2517 · 12

Niels_L 2.39
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I am curious to know about people's experiences with this scope.  I read good things but don't think it is too popular (yet).

I have the Askar FRA300 Pro + AM5 and quite like it - even though it is undersampled with my ASI294MC Pro (4.63 um pixels). I am planning to upgrade the camera only next year, probably to the ASI2600MM.  I am thinking of getting another refractor around the 700 - 1000mm, the Askar 120APO looks tempting. Any experience is appreciated!

Thanks,
Niels.
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verticalmagic 0.00
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Hi Niels,

you can take a look at the pictures I took recently with a setup close to what you target : https://www.astrobin.com/users/verticalmagic/
Overall I think it is a good scope, the optics is good and mechanics is good. It is probably not as sharp as higher end telescopes like Tak or Stellarvue. In Nina the typical HFR I get is 3.5 pixels, vs 2.7 for the FRA400 with same camera (IMX571 color).  It is more impacted by the seeing though, the HFR can easily get to 4 with a little turbulence. So maybe not the sharpest telescope on the market but quite good for the money. The reducers/flatteners are good (I have both).
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Googong_Observatory 1.20
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Hi Niels,

Below is a cut and paste that I've given to others asking about the Asker 120:

I purchased the Askar 120 in April to replace my 20+ year old Newtonian since they have similar focal lengths (840mm vs 1000mm). I also find refractors much more forgiving, e.g. no collimation and less impacted by the wind compared to a Newtonian. Overall I'm very happy with the performance of the Askar 120 APO and 1.0 x Flattener, and below are my observations:

Pros:
- Solid focuser with no issues installing the compatible ZWO EAF. 
- The scope pairs well with the ASI 2600MM and 533MM Pro cameras in relation to image scale and pinpoint stars all the way to the edge. 
- The weight of the scope, EAF, Camera, EFW and OAG combination comes in around 10kg and is no problem for the EQ6-R pro. Guiding is averaging between from 0.4-0.8 RMS, which is a result of seeing conditions and not the mount.

Cons:
- The dew shield is a bit short, however I'm managing dew with two dew heaters (one on the OTA as close as possible to the lens cell and one on the dew shield). It's dropping to -4 degrees C at the moment and I have no issues with dew or frost.
- The type of glass used in the Askar is unknown? They specify a single piece of ED glass as part of the triplet design? I'm not sure how much this actually impacts image quality?

Unknowns:
- Since I'm shooting in mono, chromatic aberration isn't really an issue. I'm not sure how OSC would perform? 
- The 2600MM Pro has an APS-C sized sensor and I have pin-point stars to the edge with very little vignetting. From watching other reviews a full-frame sensor gets good focus, but vignetting is more noticeable. This can be removed easily enough with flats. 
- Not sure how the 0.8x reducer performs and I'm not sure I would invest in one? My William Optics Z81 provides me with a shorter focal length if I need it. 

General Observations:
Now that I've got a couple hundred hours of integration time with the scope, I'm noticing the impact of seeing conditions. I get an average FWHM of around 3-3.5" where I live and I can see it is not allowing the Askar to reach it's full resolution potential. When I'm getting the rare nights of 2-2.5" FWHM the stars are much tighter and look great! FYI, all of my Astrobin images to date with the Askar 120 are around 3" FWHM. 

Hope this helps.


Regards,
Adam
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NicoAstro83 0.00
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Hello. I went from a Quattro Newton. The quality is really good. I just need to manage the processing on pix better
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fwm891 0.00
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I am curious to know about people's experiences with this scope.  I read good things but don't think it is too popular (yet).

I have the Askar FRA300 Pro + AM5 and quite like it - even though it is undersampled with my ASI294MC Pro (4.63 um pixels). I am planning to upgrade the camera only next year, probably to the ASI2600MM.  I am thinking of getting another refractor around the 700 - 1000mm, the Askar 120APO looks tempting. Any experience is appreciated!

Thanks,
Niels.

Hi Niels, I really like the 120 so much so I have 2 dual mounted on my iOptron CEM60. I use APS-C format cameras 2600 MC Pro and a Duo although I guide with a separate 80mm scope to avoid having to keep re calibrating PHD2 if I rotate the framing which I have to do if I guide with the Duo!.
Both my scopes give pin sharpe stars across a flat FoV and I have no trouble stacking the images together from the two scopes. I have the x1 and x0.8 flatteners both give flat fields with tight stars to the corners. The scopes are said to cover full frame formates but I've not tried them there as I don't have that format sensors. I have a RoR observatory which has a 2 x 2 meter internal dimension and the 120 swings round (just).
Hope this helps you.
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ToddTTucker 0.90
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I love my 120.  I took this with the .8 reducer.  I have had no issues with the flattened or .8 reducer.

https://www.astrobin.com/r1jzl1/
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Niels_L 2.39
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Thanks all! This is very helpful. Seems like most people are happy with it. Solid and decently sharp (for its price). The short dew shield would not bother me too much, the coldest it gets in winter is about 8 degreesC. I've been browsing through all the photos and am getting sold (my poor bank account hahaha).

@Adam Cox , @NicoAstro83 , I saw you also own the SW 200p / quarto newton? Although vastly different scopes, is there one or the other you prefer?
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Googong_Observatory 1.20
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Hi Niels,

Definitely prefer the Askar 120 over the SW 200P. The SW 200P is more susceptible to poor guiding if my balance is off or I have a slight breeze.

Below is a comparison between the two scopes. Both are 60mins of Ha:
  • SW200P = 12 x 300sec,
  • Askar 120 = 10 x 360sec.


From left-to-right there is:
  1. The raw image,
  2. 2x drizzle, and
  3. 2x drizzle with BlurXTerminator.


IMO the SW200P provides better resolution and contrast, which it should at F5 Vs F7 and 1000mm Vs 840mm focal length. However for the ease of use and consistent performance, I'd choose the Askar 120.

image.png


Regards,
Adam
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Niels_L 2.39
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Adam Cox:
IMO the SW200P provides better resolution and contrast, which it should at F5 Vs F7 and 1000mm Vs 840mm focal length. However for the ease of use and consistent performance, I'd choose the Askar 120.


Thanks Adam!  Those photos are very helpful!
Indeed there is the difference in resolution but I do agree that the ease of use will play a big role for me, as still a newbie in the field.  I probably won't get the same quality out of a reflector (I already had trouble getting my 8SE SCT perfectly collimated...) as a refractor.
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dgalanaud 1.20
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Hello Niels
Just bought the 120 apo with the 1x field flattener a few days ago. It fitted a double purpose, very similar to what you are looking for:
- having a greater focal length than my WO RedCat 70 for smaller targets, using it with the 2600MC/MM cameras
- a more unconventional usage: replacing my Celestron Edge 8 HD for galaxy season, combining it with a 183MC Pro camera. This may seem bizarre, but the 120 apo/183MC combination gives you the same resolution as the Edge8/533 MC. My rational was that the smaller aperture would be at least partially compensated by the absence of central obstruction (which reduces significantly the contrast). The major problems with the Edge were that since I live in Paris I have to travel to the countryside to image, in a very damp environment and have major difficulties not getting dew on the Schmidt plate (even with active heating and a large dew shield !). This, of course, in addition to the regular losses of collimation during the car trip.

I was lucky enough to get 3 clear nights and could test both combinations. Results were beyond all my expectations. You can find the 2600MC test here: https://www.astrobin.com/zhhx8y/

I run the 183 MC test on M51. Since the galaxy was low on the horizon, the quality was much lower but still individual frames were as good as the ones I got with the Edge HD under the best conditions (no dew, perfect collimation).

As a practical point of view, build quality is excellent. The telescope is bulky, but still light enough to fit on the ZWO AM5 with the light pier extension and without counterweights. The carrying case is very nice, and, with a little digging, you can fit the telescope with the ZWO focuser attached.

Hope it helps

Best

Damien
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Photon_Collector 1.43
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Check out my profile to see the last ~6-7 images with the Askar 120, I bought it in March and am loving it so far. Can't wait to take it to an actual dark site as all the pics in my profile are from bortle 7
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Niels_L 2.39
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Hi @Damien Galanaud, thanks for the details. Indeed, looks like a great scope! Though, there is a strange star in the bottom right (right of the galaxy)?

@Photon_Collector, photos look good!  Everyone is quite happy about the scope! Though, wonder how it will match with the ASI294MC... I am 99% over the hurdle of buying, so maybe in a few weeks I could share my photo 
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NicoAstro83 0.00
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Hello, look my last picture witch APO120
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dgalanaud 1.20
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Hi @Damien Galanaud, thanks for the details. Indeed, looks like a great scope! Though, there is a strange star in the bottom right (right of the galaxy)?

@Photon_Collector, photos look good!  Everyone is quite happy about the scope! Though, wonder how it will match with the ASI294MC... I am 99% over the hurdle of buying, so maybe in a few weeks I could share my photo 

The strange star is due to the processing (I played a little bit with Blur Xterminator to sharpen the galaxy but then added back a non deconvoluted star map with pixelmath to keep them nice and round in the cluster instead of pinpoint). Since I was satisfied with the global results, I did not try to do it again to fix this single aberrant star.
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Niels_L 2.39
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I decided to join the club and bite the bullet (bullet being my bank account )!  Below my 'unboxing photo' 

Will have to wait till next weekend to get some clear skies but I am excited! It is a beast compared to my FRA300...  Does anymore use an extension pillar on the tripod or will it be fine without?  (I am using the AM5 with TC40)

IMG_3421.jpeg
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AstroNovixion 0.00
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I decided to join the club and bite the bullet (bullet being my bank account )!  Below my 'unboxing photo' 

Will have to wait till next weekend to get some clear skies but I am excited! It is a beast compared to my FRA300...  Does anymore use an extension pillar on the tripod or will it be fine without?  (I am using the AM5 with TC40)

IMG_3421.jpeg

Congrats! Look forward to hearing what you think about it!

I have a very similar FL/Aperture scope (Esprit 120ED) and the PE200 pier extension. The pier is pretty useful since the scopes are super long. It also depends on where you are imaging even with the pier extension you should still be careful where the tripod legs are and your meridian limits.  

Clear Skies!
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javaruck 6.45
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Does anymore use an extension pillar on the tripod or will it be fine without?  (I am using the AM5 with TC40)


I highly recommend that you get the PE200 pier extension. I have the 120 APO and it's a pretty long imaging train with my mono setup. Congratulations on the new scope, I've been very happy with mine.
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dgalanaud 1.20
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Congratulations !
I am sure you will have fun with it.
Definitely get the pier extension. If you image near the zenith, you will have a high risk of collision. Another very useful accessory is an electronic focuser: since the tube is so long, change in focus due to temperature related contraction during the night  are much more significant than with shorter tubes. The ZWO EAF is the most obvious solution. You can fix it very easily on the telescope, and if you dig the foam a little bit, it will still fit inside the carrying case.
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Niels_L 2.39
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Damien Galanaud:
I am sure you will have fun with it


Thanks, I can't wait! Already looking what would be the first target... I shot the Helix neb with the Askar FRA300 but it did not get much detail. I'm now considering a redo! Or a retake of the sculpture galaxy... Excited! Let's hope for some good clear skies!

Another question - I am using the ZWO filter drawer (21mm) and the ASI294MC Pro (17.5mm). To get the back focus to 55mm, I need another 16.5mm. How important is it to get this exact to 55mm with the 120APO? Some YouTubers had 57mm. What is your experience?
Do you find much difference in back focus distance between the 1x and 0.8x?
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dgalanaud 1.20
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You should have a 16.5 mm extension ring coming with your 294MC pro, it is a perfect match and will get you to 55 mm. The only theoretical issue is that the filters add a little bit of back focus (1/3 the thickness of the filter). In my experience with the 1x flattener, it has no effect.
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Niels_L 2.39
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I tried to install the flatteren but it seems that the ring for eyepieces is completely stuck to the rotator ring… Anyone experienced this as well? 
I read up on the “cold weld” thread but it looks like the rotator has some internal rings/tube/parts (or so) and don’t want to break it just yet😕 
IMG_3422.jpeg
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fwm891 0.00
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AST_8822.jpgNiels,
Mine break the otherside of the rotator. The ALL threads were tight to start with but released OK.
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Niels_L 2.39
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Francis:
The ALL threads were tight to start with but released OK


Hi Francis,
Thanks for the pics, helpful for confidence boost to put some more force on it... I had to go buy an oil filter removal clamp and had to put some oil in it... But finally managed to get it loose!
It might have gotten temperature fluctuations during transportation and got stuck. I was a bit afraid to damage the rotator before using  I was sweating hahaha
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Googong_Observatory 1.20
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Congratulations on the new scope. I'm looking forward to your first image!
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Niels_L 2.39
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Adam Cox:
Congratulations on the new scope. I'm looking forward to your first image!

Me too!  Currently having a storm here in Cape Town.... The weekend should be getting better.

I'm considering using the 0.8x on the Helix Neb to join the wide field Overall Photons project. Though, the sculpture is still there too... I need more time in a night! 
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