ASKAR FMA180 40mm aperture apochromatic telescope.

[Clarkey]

2 hours ago, Adam J said:

Depending on which filters you removed when you modified the 600D then you may actually already have an effective UV/IR cut in place. 

I'll have to try the mono camera and see how it fares. It was not a full spectrum modification so it might be blocking the blue as you suggest.

I have realised the single sub above is through an l-extreme so not very representative!

[PadrePeace]

My latest with the Askar 180, 2” L3 filter, and the ASI294MC cooled to -10 at 120 gain. Only 1hr 40mins of 30s subs with a 20% moon. Still a good image to support the L3 discussion here at the moment with some very bright white stars.  Enjoy…. and clear skies guys. 

[Adam J]

Three hours of RGB with the ASKAR, no luminance.

Dont get to do the long 40 hour intergrations I used to these days but I was quite happy with some of the fainter dust starting to  come in even without any luminance.

 

Adam

Edited January 14, 2022 by Adam J

[PadrePeace]

California Nebula from my Askar FMC180 in Optalong L Extreme dual band and straight ASI294MC RGB for stars and the IFN. 13hrs (4hrs NB and 9hrs RGB). 
I used my own Darks only calibration technique to get around the 294MC vs L-extreme Flats problem. See here for more. https://stargazerslounge.com/topic/388826-294mc-pro-l-extreme-and-a-bunch-of-flats/?do=findComment&comment=4197379

 

 

[Adam J]

3 hours ago, PadrePeace said:

California Nebula from my Askar FMC180 in Optalong L Extreme dual band and straight ASI294MC RGB for stars and the IFN. 13hrs (4hrs NB and 9hrs RGB). 
I used my own Darks only calibration technique to get around the 294MC vs L-extreme Flats problem. See here for more. https://stargazerslounge.com/topic/388826-294mc-pro-l-extreme-and-a-bunch-of-flats/?do=findComment&comment=4197379

 

 

Really nice image! I do like the dust seen here that you don't normally see in pure duel channel narrow band, great work all round. 

Adam

[Quetzalcoatl72]

Has anyone used a 2" filter with this scope? I don't want to have spend another 100 on a optlong pro lp filter for the 1.25". Anyone know how I can fit it in-between my asi533 and askar?

[Adam J]

4 hours ago, Quetzalcoatl72 said:

Has anyone used a 2" filter with this scope? I don't want to have spend another 100 on a optlong pro lp filter for the 1.25". Anyone know how I can fit it in-between my asi533 and askar?

It threads onto the front of the scope in front of the objective onto the same thread you used for the lens cap. To be honest its the best place for it you should not get reflections and you should not get any issues with pass band shift. Clearly its exposed to the elements though so I use a dew shield i made myself to protect it in use. Finally it wont cause any flats issues with dust on it etc from that location. 

Adam 

Edited January 17, 2022 by Adam J

[Second Time Around]

I use this as a finderscope and for night vision.

To make a longer dew cap I just screwed on a 48mm extension tube and my filters screw onto this.  It's certainly a very versatile piece of kit!

[Quetzalcoatl72]

5 hours ago, Adam J said:

It threads onto the front of the scope in front of the objective onto the same thread you used for the lens cap. To be honest its the best place for it you should not get reflections and you should not get any issues with pass band shift. Clearly its exposed to the elements though so I use a dew shield i made myself to protect it in use. Finally it wont cause any flats issues with dust on it etc from that location. 

Adam 

Great, yeah! does having dew shields cause vignetting, i don't have one but if i position my dew heater right it should be ok hopefully

[Adam J]

2 hours ago, Quetzalcoatl72 said:

Great, yeah! does having dew shields cause vignetting, i don't have one but if i position my dew heater right it should be ok hopefully

Just don't make it more than about 2 inches long. 

Edited January 17, 2022 by Adam J

[PadrePeace]

I have a homemade dew shield that sits 6cm forward of the end of the Askar scope with an exit diameter of 6.5cm and with an ASI294 4/3rds sensor have never seen vignetting on my Askar 180. It sits over the dew strap so is naturally a bigger diameter than the scope which means I get away with a longer dew shield and hence that little bit more protection from cold air and any stray moon or lamp light. It additionally warms being over the dew strap which gives added protection . 

[rnobleeddy]

Has anyone worked out how to fit a focuser?

I've only had this out for one night and whilst I thought I'd managed to achieve focus manually using the old DSLR live view + zoom, the result suggests otherwise. Although I appear to have achieved consistency, as I managed to same result on two targets!

Life's too short to worry about manually focusing, but I guess it'd be  custom bracket  + belt?

 

Edited January 18, 2022 by rnobleeddy

[Quetzalcoatl72]

I know people use this for star trackers but has anyone actually tried to put it on a large scope like the neq6. I currently mount it on the ed80 and just use that, but it seems a waste to bring out the ed80 and not actually use it because the askar is too light to have any counterbalance. i think the bar is actually heavier lol.

Edit: oh thats right i need a guidescope, i might get away with using one weight right to the top if i create a setup somehow.

Edited January 19, 2022 by Quetzalcoatl72

[900SL]

Anybody use the Bahtinov mask that is available for this scope? If so, how is it working out?

 

[Adam J]

19 hours ago, rnobleeddy said:

Has anyone worked out how to fit a focuser?

I've only had this out for one night and whilst I thought I'd managed to achieve focus manually using the old DSLR live view + zoom, the result suggests otherwise. Although I appear to have achieved consistency, as I managed to same result on two targets!

Life's too short to worry about manually focusing, but I guess it'd be  custom bracket  + belt?

 

Looks more like a stacking issue to me, as if you have includrd some out of focus stars in the stack with some in focus subs too. 

Adam

[rnobleeddy]

1 hour ago, Adam J said:

Looks more like a stacking issue to me, as if you have includrd some out of focus stars in the stack with some in focus subs too. 

Adam

I'll check the stack again, but I didn't touch the setup during this time, and I'd guess drift might look different? 

I did use a narrowband dual filter, so wondered if this is exacerbating the effect, if the focus is slightly out on the red side, that might explain the ring around the star?

Found https://grapeot.me/auto-focus-solution-for-sharpstar-fma180.html which I will probably print and try.

[Adam J]

1 hour ago, rnobleeddy said:

I'll check the stack again, but I didn't touch the setup during this time, and I'd guess drift might look different? 

I did use a narrowband dual filter, so wondered if this is exacerbating the effect, if the focus is slightly out on the red side, that might explain the ring around the star?

Found https://grapeot.me/auto-focus-solution-for-sharpstar-fma180.html which I will probably print and try.

RGB are really quite close in this scope as demonstrated by others using OSC cameras (assume this is an OSC?), once you have used a L3 filter its virtually perfect correction between 420 and 680nm. 

So its nothing to do with the filter you are using. 

I would take a look though your subs. 

Adam

 

[rnobleeddy]

5 hours ago, Adam J said:

RGB are really quite close in this scope as demonstrated by others using OSC cameras (assume this is an OSC?), once you have used a L3 filter its virtually perfect correction between 420 and 680nm. 

So its nothing to do with the filter you are using. 

I would take a look though your subs. 

Adam

 

You're right - I didn't have time to re-stack them, but looking at a few individual subs doesn't show the same issue.  Thanks!

[Dindale]

Relative newbie here. I am still working with normal photography lenses and a simple (MSM) tracker and consider this Askar a nice step up before I go “full APO”. My current tracker is way too light for my Canon 6D mk II and 70-200 f2.8, less so with my Zeiss Makro-Planar 100mm. I am planning to go for a real GOTO mount and dedicated astro camera and guiding and everything, but first I want to practice on this lens (and filters) before I invest further. I live in a Bortle 4 area but with some nasty LED streetlights relatively close. Reading this thread I have come up with the following shopping list to get started:

1. Askar FMA180

2. Baader T2 EOS adapter

3. Astronomik L3 filter, M48 to screw on the front of the Askar, not sure if this helps against LED lights?

4. Baader T2 fine adjustment rings, not sure if this is needed in this setup?

Am I missing anything here or other advice you can give me? Thanks!

[Adam J]

8 hours ago, Dindale said:

Relative newbie here. I am still working with normal photography lenses and a simple (MSM) tracker and consider this Askar a nice step up before I go “full APO”. My current tracker is way too light for my Canon 6D mk II and 70-200 f2.8, less so with my Zeiss Makro-Planar 100mm. I am planning to go for a real GOTO mount and dedicated astro camera and guiding and everything, but first I want to practice on this lens (and filters) before I invest further. I live in a Bortle 4 area but with some nasty LED streetlights relatively close. Reading this thread I have come up with the following shopping list to get started:

1. Askar FMA180

2. Baader T2 EOS adapter

3. Astronomik L3 filter, M48 to screw on the front of the Askar, not sure if this helps against LED lights?

4. Baader T2 fine adjustment rings, not sure if this is needed in this setup?

Am I missing anything here or other advice you can give me? Thanks!

The first thing I would say is that this is a valid imaging scope and I would not consider it a stepping stone rather simply a tool in your box for working at this focal length / FOV. I own an Esprit 100 and lots of other very expensive accessories and I still enjoy imaging with this scope as part of my mobile / wide feild imaging rig. I use it on a AZ GTI  in EQ mode for GOTO. So personally i would go with all those things guiding / good mount and then when you get a larger scope I would keep this for wider views.

In terms of 3. nothing really helps for RGB imaging vs LED lights you will just have to live with them or get a duel narrow band filter if your camera has been modified. I would get the adjustment rings especially for a full frame sensor as you will need to get it spot on. Remember that nothing ever really covers a full frame no matter the claims unless you spend some very serious cash. Hence be prepaired to crop.

Personally I would chuck a little more cash in and get and AZ GTI with a wedge and counter weights bar to use the scope in goto even as a interim step as if your current tracker is not coping I doubt that chanigng to the FMA180 will help too much over the canon lense combinations that you have been using.

If you are not going to use a auto focusing solution then i think that a bahtinove mask is avaliable for the FMA180 and that it has been discussed earlier in this thread, for me that would be an essential purchase. Finally I would say get a 2 inch dew strap and 12 volt power source as designed for use on 2 inch eyepeices. It will fit the FMA180, I would not image without one. You will not need a dew controller for such a low power strap just run it all the time at full.

Adam

 

Edited January 21, 2022 by Adam J

[Dindale]

8 hours ago, Adam J said:

The first thing I would say is that this is a valid imaging scope and I would not consider it a stepping stone rather simply a tool in your box for working at this focal length / FOV. I own an Esprit 100 and lots of other very expensive accessories and I still enjoy imaging with this scope as part of my mobile / wide feild imaging rig. I use it on a AZ GTI  in EQ mode for GOTO. So personally i would go with all those things guiding / good mount and then when you get a larger scope I would keep this for wider views.

In terms of 3. nothing really helps for RGB imaging vs LED lights you will just have to live with them or get a duel narrow band filter if your camera has been modified. I would get the adjustment rings especially for a full frame sensor as you will need to get it spot on. Remember that nothing ever really covers a full frame no matter the claims unless you spend some very serious cash. Hence be prepaired to crop.

Personally I would chuck a little more cash in and get and AZ GTI with a wedge and counter weights bar to use the scope in goto even as a interim step as if your current tracker is not coping I doubt that chanigng to the FMA180 will help too much over the canon lense combinations that you have been using.

If you are not going to use a auto focusing solution then i think that a bahtinove mask is avaliable for the FMA180 and that it has been discussed earlier in this thread, for me that would be an essential purchase. Finally I would say get a 2 inch dew strap and 12 volt power source as designed for use on 2 inch eyepeices. It will fit the FMA180, I would not image without one. You will not need a dew controller for such a low power strap just run it all the time at full.

Adam

 

Hi Adam,

Thanks for te elaborate answer, I really appreciate it! I have been hinging on two thoughts: get a decent EQ mount first and work with the camera and lenses I have right now, or try to get as much out of the MSM tracker with maybe a lighter lens, like the AFM, improve my skills and then go for the EQ mount. I bought the MSM just to see if I could get something out of my current gear, and I was quite surprised what is already possible, and that made me hungry to go further. Last time I tried this was roll film on a Russian camera back in the eighties… Any thoughts on this (not on the roll film camera)?

I can get decent 60 sec subs with the 100mm, which is less than 700 grams. 

The 70-200 with tripod collar comes in at some 1600 grams, and I can see and hear the MSM struggling with it. I got a half decent shot of Orion a week ago on a damp night with the big Canon but could not go beyond 10 second subs.

That is why I thought by reducing the weight significantly I could continue to use the MSM for a while but get a longer focal length. Polar alignment is still an issue then with the longer focal length (as opposed to the 100mm Zeiss).

Bahtinov mask, lens warmer and power source(s) are all there, I just have to exercise some more discipline to use the warmer.

 

[900SL]

What are you guys doing for a front dew shield/hood? Anything out there that works with a 2" filter installed in the front thread? 

[Adam J]

12 minutes ago, 900SL said:

What are you guys doing for a front dew shield/hood? Anything out there that works with a 2" filter installed in the front thread? 

I 3d printed one. Might still have the file not sure. 

[900SL]

2 hours ago, Adam J said:

I 3d printed one. Might still have the file not sure. 

Thanks Adam, appreciated but I don't have access to a 3D printer

I found this on TS, I'll see if FLO have one:

M48 to M63 conical shield, ~ 60mm long, with an internal thread for 2" filters? Should fit I think? 

 

 

 

 

[Adam J]

1 hour ago, 900SL said:

Thanks Adam, appreciated but I don't have access to a 3D printer

I found this on TS, I'll see if FLO have one:

M48 to M63 conical shield, ~ 60mm long, with an internal thread for 2" filters? Should fit I think? 

 

 

 

 

Probably so long as it's not too hard to get the filter in.