ASKAR FMA180 40mm aperture apochromatic telescope.

[Adam J]

28 minutes ago, Space Oddities said:

Sounds very tempting! I am thinking of replacing my Samyang 135mm with this small APO. The main advantage I see is the low weight compared to the Samyang. It would allow me to mount it to my AZ-GTi without a counter weight, and put that on my narrow balcony. The motivation to go out during winter is quite low, so that could be a nice way to still image some winter targets, from the comfort of my bed. And also to take it with me while traveling. 

Adam, have you tried mounting an OAG? I did the maths, and ZWO's OAG + EFW + 11mm spacer + ASI1600 = 54mm, which theoretically should be fine for the back focus of 55mm? That would make it a super tiny imaging platform to take everywhere!

I considered it but I decided that the weight of a 30mm guide scope was not going to kill it and off axis guiders can be fiddly too. 

Finally because i am a perfectionist (its really not that bad) I decided to add a tilt adaptor and so i would struggle to fit it between that and the auto focuser. 

Adam 

Edited October 9, 2020 by Adam J

[Space Oddities]

Thanks for your feedback! I read some additional reviews and it seems like a really nice little scope. I think I'll get one, to end the frustration I have of not imaging enough during winter time... I have a few lenses that I need to sell anyway, so this will finance that  

[PadrePeace]

Here's my effort with the ASKAR 180 at NGC7000.  A very busy target with so many stars but chosen to test the scope into the corners. Doubt it will win IoTD but this new scope is setting the standards at only 180mm for a flattened triplet with ED (unspecified) glass, likely to be 51 class I'm guessing.

 

Rig:

IOptron Starguider Pro with ipolar.

SW 1.75'' tripod

Canon 650D modified

Askar 180/40 triplet

Pegasus Focus Cube V2 mounted with one of AdamJ's 3D printed casings.

Camera and scope mounted through bits stollen from a Star Adventurer mount to give me better control of initial target alignment. All comes in at just over 2 kg so well within Skyguider Pro spec (5kg).

Home made 12volt 6.6 amp hr LiPo power box which doubles as a counterbalance weight.

Red Dot Finder for initial target alignment.

Data:

24 x 240s subs 1600ISO  tracked but not guided. ipolar align accuracy really helps here.

Flats/Bias/Darks to suit

Misc:

Capture through NINA and processed in PS.  This has been very slightly cropped to remove sub overlap issues as I shot this over two nights. Stars were good to the very corners so the in flattener works with a crop sensor.

I had blue fringing on the brightest white stars. I chose to process it out but this could have been left not distracting at all in my judgement. Your preferences may vary. 

I'm chuffed with the results especially for only 1.6hrs integration. 

Hope this helps y'all.

Below is cropped, the second is uncropped but as you'll see the star shape doesn't change.

Edited October 13, 2020 by PadrePeace
Extra pic

[Adam J]

31 minutes ago, PadrePeace said:

Here's my effort with the ASKAR 180 at NGC7000.  A very busy target with so many stars but chosen to test the scope into the corners. Doublt it will win IoTD but this new scope is setting the standards at only 180mm for a flattened triplet with ED (unspecified) glass, likely to be 51 class I'm guessing.

I'm chuffed with the results especially for only 1.6hrs integration.

It is an interesting design with two ED elements, its very hard to say what they might be, could be two different types as per the FLO scopes even, but as you say seems more likely to be a cheaper ED glass. Correction is not perfect but F4.5 is very fast for a refractor after all and CA at that speed is still quite good considering the cost.

Great image and just think where it could be taken with 4x that intergration and this with not filters fitted at all.

Need to get my portable rig together!

Good to see that the focuser mount is working well for you.

Adam

 

Edited October 12, 2020 by Adam J

[PadrePeace]

I run this same rig with the focuser, a  460EX/EFW guided by a 60/30 mini guide scope and a QHY5L-II M and so if you could slip a Lum layer of Ha in there somewhere it has the makings of a very capable scope. I’ve additionally also played with mounting the DSLR as a counterweight for double shooting. No images yet though but balance will be key.

Happy to share the SW adventurer adjustment mod with anyone having difficulties with the IOptron system.

Edited October 13, 2020 by PadrePeace
Pic added

[Space Oddities]

I received my copy of this little scope. I haven't been able to use it so far, the weather has been horrible here in Bavaria.

I noticed the mounting screws are made of metal, without a plastic washer at the end, which leaves marks on the scope. Not cool...

So I found this cheap carbon fiber sticker they sell for cars, and covered the main tube with it to protect against marks. It's pretty nice! However, the sticker adds a fraction of a millimetre to the tube's diameter, so it doesn't slide as smoothly inside the rings. 

Later on I found some old plastic screws that happen to be the same size as the original metal ones. Paired with the carbon fiber sticker, they won't damage the aluminium elements, and still provide a secure attachment  

For mounting, I'm using this cheap Mengs Arca Swiss plate, to which I added a finder shoe for the guide scope.

Now I'm wondering if it makes sense to mount a mono cam to this little scope. An OSC paird with an Optolong L-eNhance or similar, would perhaps be a better companion to this portable scope.
 

[Adam J]

1 hour ago, Space Oddities said:

I received my copy of this little scope. I haven't been able to use it so far, the weather has been horrible here in Bavaria.

I noticed the mounting screws are made of metal, without a plastic washer at the end, which leaves marks on the scope. Not cool...

So I found this cheap carbon fiber sticker they sell for cars, and covered the main tube with it to protect against marks. It's pretty nice! However, the sticker adds a fraction of a millimetre to the tube's diameter, so it doesn't slide as smoothly inside the rings. 

Later on I found some old plastic screws that happen to be the same size as the original metal ones. Paired with the carbon fiber sticker, they won't damage the aluminium elements, and still provide a secure attachment  

For mounting, I'm using this cheap Mengs Arca Swiss plate, to which I added a finder shoe for the guide scope.

Now I'm wondering if it makes sense to mount a mono cam to this little scope. An OSC paird with an Optolong L-eNhance or similar, would perhaps be a better companion to this portable scope.
 

Depends comparison between my ASI1600mm pro and a DSLR with similar pixel size shows me that there is a nice improvement in detail with the mono camera due to it having all pixels and that the optics support that. In a dense star feild for me its the difference between the stars starting to blur together and them remaining seperated. Also which OSC would you go with? A ASI183mc would seem to be a good choice but in reality its going to be a sacrifice in FOV and that sensor is not the fastest on the marked. An ASI533mc pro had good sensitivity but again your losing out in FOV and this scope can deliver on large sensors. A 294mc has even larger pixels and that pritty much leaves something like a ASI2600mc and thats one expensive camera to pair with a £350 refractor in my opinion. I did see a QHY247 second hand recently and was tempted.

Another consideration is that with OSC you will not be able to refocus per LRGB filter and that is going to result in worse CA effects as this scope is not perfectly corrected as I note above.

All in all when mobile imaging I want to collect as much data as I can in as little time as possible and so to me that means a mono camera shooting LRGB and Proper Narrowband filters. The only argument for OSC is that you will not need to take the filter wheel and refocus between filters, thats why I made sure to implement an auto fosuser on mine.

Adam

[Space Oddities]

Well, I have an APS-C DSLR already as well as an ASI1600MM. What I'm looking for is a very portable solution, that's convenient to use when I'm travelling. I'm ready to give up some image quality by going to an OSC, if I don't have to drag along a filterwheel, filters, and an autofocuser... or having to refocus in the middle of the night.

I was thinking an ASI183MC or ASI533MC, paired with an Optolong L-eNhance or L-eXtreme, would make a nice and tiny setup for chasing emission nebulae   It would sit nicely between a more serious mono camera, and a non-modded, non-cooled APS-C DSLR.

FOV seems similar on both, and though the smaller pixels and higher resolution of the 183 are attractive, the lack of amp glow, the full well and dynamic range of the newer 533 are nice to have as well.

Also, for broadband targets, I'm considering the Baader semi APO filter (basically a 'Fringe Killer' and a 'Moon & Skyglow' combined into one filter). It's been designed to reduce colored halos on achromatic refactors, and someone over at Cloudy Nights said it does a good job with the Askar 180   Post-processing should be able to further remove any CA left, as you can see on this picture, posted on CN: https://drive.google.com/file/d/10FEAZ0oeofu78N3nq80zudUO51_L7V0q/view

What do you think?

[Adam J]

2 hours ago, Space Oddities said:

Well, I have an APS-C DSLR already as well as an ASI1600MM. What I'm looking for is a very portable solution, that's convenient to use when I'm travelling. I'm ready to give up some image quality by going to an OSC, if I don't have to drag along a filterwheel, filters, and an autofocuser... or having to refocus in the middle of the night.

I was thinking an ASI183MC or ASI533MC, paired with an Optolong L-eNhance or L-eXtreme, would make a nice and tiny setup for chasing emission nebulae   It would sit nicely between a more serious mono camera, and a non-modded, non-cooled APS-C DSLR.

FOV seems similar on both, and though the smaller pixels and higher resolution of the 183 are attractive, the lack of amp glow, the full well and dynamic range of the newer 533 are nice to have as well.

Also, for broadband targets, I'm considering the Baader semi APO filter (basically a 'Fringe Killer' and a 'Moon & Skyglow' combined into one filter). It's been designed to reduce colored halos on achromatic refactors, and someone over at Cloudy Nights said it does a good job with the Askar 180   Post-processing should be able to further remove any CA left, as you can see on this picture, posted on CN: https://drive.google.com/file/d/10FEAZ0oeofu78N3nq80zudUO51_L7V0q/view

What do you think?

I would go with the 533 in a mobile setup as its a cleaner sensor and you will not have to worry so much about calibration frames. In a mobile setup its also important to gather data as fast as possible so I would select the more sensitive camera, which is the 533...but the ASI1600MM Pro is more sensitive still so I will be sticking with that even for mobile work.

I was thinking about using a narrower UV/IR CUT such as the ASTRONOMIK L3 or a baader semi-app to help remove the blue bloat as you suggest, but its really not that bad anyway. There are also other LRGB filter sets with different cut off in the blue and red such as the ANTILA LRGB filters.

The Semi apo filter is actually a LP filter too. If you are at a reasonably dark site with the Mono camera lum via a fring killer might be a better option. Or place it in line with your LRGB filters by screwing a 2 inch one onto the front of the scope. But looking at PadrePeace's image above I am not 100% convinced its a nessasary step.

Adam

Edited November 18, 2020 by Adam J

[nicoscy]

I only do EAA, so take with a pinch of salt: NGC7000 7 frames x 10 sec each at 320 gain, ASI533, ZWO duoband filter. No calibration frames.

[Adam J]

7 hours ago, nicoscy said:

I only do EAA, so take with a pinch of salt: NGC7000 7 frames x 10 sec each at 320 gain, ASI533, ZWO duoband filter. No calibration frames.

 

 

Very nice for such a tiny integration of just over 1 min. Really need someone to post a picture of something other than the north America nebula though lol. 

I have a AZ GTI on order right now.fornuse with this scope. Hopefully arrives at the start of December. 

[nicoscy]

Well, you DID ask. All about 60 to seventy second integrations and under a full moon on the same evening, same gain and 10 sec exposures stacked....

[Adam J]

Really happy to see that @FLO have taken up this great little product. 

 

[nicoscy]

Here's some more examples EAA style, again, 7 x 10sec Gain 350 no calibration frames from the same evening as the previous ones I posted (so please take into consideration full moon). Pacman, NGC6888, Heart and Soul nebulae.

Yep, a great little lens and FLO has them well priced too. I am tempted now to get the 200mm f4 lens since I repurposed my ASKAR 180 as a finderscope. Deep Sky Dad has EAF autofocus kits available as well!

[Adam J]

I have been doing some testing with a Astronomik L-3 Luminance filter to see if this mild filter is able to remove the small blue bloat that the FMA 180 has.

I have heard that people have used the baader semi-apo and the finge killer filters with this scope to good effect in reducing the blue fringes on brighter stars.

However, it has been my belief that such filters are unnessasarily harsh for this scope and more than is required to remove the amount of bloat I have been seeing. Hence I have tried a combination of Astronomik L-3 in line with my Baader filters to slightly clip either end of the spectrum.

Here are my results for the blue channel with and without an Astronomik L-3 filter in line with my Baader Blue CCD filter.

First with Baader Blue Filter only:

And then with the Astronomik L-3 and Baader Blue Filters in series. (2 inch L-3 on the nose and 1.25 inch in the filter wheel).

I would call that quite a dramatic effect / improvement!

You lose a little bit of signal in the blue channel and less in the lum channel in comparison to without the L-3 filter, but not that much so I see it as a worth while trade off given Green and Red are vertually uneffected.

Just increase blue channel exposure by about 25% and keep L,G,R channel exposures the same, colour balance remains good.

Target was M44. Clearly a large crop this being presented at greater than 1:1.

I expect that this would produce a good improvement in a OSC camera too.

Star FWHM is now extreamly close across all four LRGB channels and so I am hopeful of some good perfomances to come.

Hope this is usefull to my fellow ASKAR FMA 180 users.

Adam

 

 

 

Edited January 29, 2021 by Adam J

[Space Oddities]

Thanks Adam, that's very helpful!

[alcol620]

Bought the ASKAR 180 but run into trouble with out of shape stars in 2 of the corners.  Camera is a modified Canon 1200d. I think it might be sensor tilt?

[Adam J]

11 minutes ago, alcol620 said:

Bought the ASKAR 180 but run into trouble with out of shape stars in 2 of the corners.  Camera is a modified Canon 1200d. I think it might be sensor tilt?

I would have to see an image to know for sure.

But with a DSLR its normally the T-adaptor that causes tilt. Its not actually a very good way to attach a lens to a sensor.

Adam

Edited January 29, 2021 by Adam J

[alcol620]

56 minutes ago, Adam J said:

I would have to see an image to know for sure.

But with a DSLR its normally the T-adaptor that causes tilt. Its not actually a very good way to attach a lens to a sensor.

Adam

do you mean the T-ring to EOS adapter taht attaches the Canon?

[Adam J]

16 hours ago, alcol620 said:

do you mean the T-ring to EOS adapter taht attaches the Canon?

Yes they are famous for creating tilt some cheaper ones are much worse than others. 

[alcol620]

Thanks Adam, what would a "good" one be?

[Adam J]

55 minutes ago, alcol620 said:

Thanks Adam, what would a "good" one be?

I would try the Takahashi or baader one from FLO as opposed to the astro essentials. But before you do that test to see if it is the problem is it is the distortion pattern will change as you rotate the camera in the scope rings as it will follow gravity. 

[alcol620]

Thanks Adam, much appreciated. If we ever get any clear nights??

[Space Oddities]

Apparently the Askar 180 will soon have a little brother!

 

[Space Oddities]

Well that's funny!  Yesterday I was wondering if there was a Bahtinov mask small enough to be mounted on the Askar 180. They're all designed for bigger telescopes and probably won't work on this 2" front element...

And today, totally by mistake, I found this upcoming Bahtinov mask! Looks great and reasonably priced.

 

Also they have released an M48 adapter, to replace the default T2 one. That might be a better fit to attach my filter slider, it's really not practical right now. 

These don't seem to be in stock yet, but I guess we'll see them soon in our favourite astro webshops!