110 replies to this topic

[JimTheEngineer]

Figured it out. Tightened up the rotator screw and then unscrewed the rotator off the back. Then unscrewed the rear lens using a plastic/rubber hand jar opener. The rear lens on this particular scope was only hand tight, so didn’t need a camera lens spanner tool to screw it off. Cleaned the backside of the rear lens and I’m good now.

It was rather cloudy tonight, but managed a single 10s frame (tracking not guiding) using an APS-C sensor (ASI2600MC). All I did was to STF Autostretch the FITS image in Pixinsight and run Aberration Inpector. No calibration frames or processing. Stars look good…

Edited by JimTheEngineer, 08 November 2024 - 01:43 AM.

[JimTheEngineer]

However, I have a lot of tilt and the stars in my guide camera are not perfect through the OAG. The image was run through ASTAP Inspection Tools. Didn’t have time to adjust tilt out. Even with tilt, note how low the off-axis aberrations are! This scope is nice and stars are really small…

Edited by JimTheEngineer, 08 November 2024 - 01:28 AM.

[PeterWar]

It's ludicrous, but I can import a brand new Tak FSQ-85EDX including ALL accessories including flattener, reducer, extender, diagonals, finders etc from Hong Kong or Japan CHEAPER than I can buy a new SQA85 from the local dealer (same local dealer has FSQ85 more than double the HK/JP price).

Warranty...not really worried with a Tak TBH in all the 20+ Taks I have owned.

I know the Vixen VSD90SS is expensive even from Japan, but I find it very alluring.

Dismayed to hear about the shavings on the SQA rear - could you have lens bulb dusted it off yourself Jim?

+1 to this comment. Will buy a Vixen VSD90SS in Japan this month and will report back. It would be interesting to compare it with the SQA85.

[Apennine]

I made the decision to look at my rear lens with a flashlight too, I also had a piece of debris  similar to Jim. Pretty disappointing. I couldn't get the rear element off, so I made a 3d printed tool. I uploaded it here in case anyone else needs it. But, like Jim once I removed the lens the debris blew right off.

 

I have incorporated the Baader M68 tilter, and things are looking pretty good to me! 

 

 

 

 

[Xav]

For those of you who have removed the manual rotator to get access to the rear lens, does it seem possible to replace the manual rotator with a standard adapter/extension tube? I'm thinking about getting this scope and putting an electronic rotator on it (PLL Arco or Pegasus Falcon) and removing the manual rotator would reduce risks of tilt.

[Apennine]

For those of you who have removed the manual rotator to get access to the rear lens, does it seem possible to replace the manual rotator with a standard adapter/extension tube? I'm thinking about getting this scope and putting an electronic rotator on it (PLL Arco or Pegasus Falcon) and removing the manual rotator would reduce risks of tilt.

I think it would be doable, but maybe with a custom adapter. It's recessed, and larger than M68. I am not sure of the interface, and was a bit of a pain to take apart. FWIW, I have a Falcon rotator on mine, and it seems ok. I am using the manual rotator to set the orientation of the Falcon rotator, so it's good for that at least. 

[Xav]

Ah yes, you need something to set the orientation of the rotator at least on the falcon. That's a bit unfortunate.

Thanks for the reply!

[JimTheEngineer]

Great job on eliminating the tilt! Looks like a perfectly flat field. Below is a pic of the jar opener I used.

[charles.tremblay.darveau]

Received my SQA85 today, luckily no metal debris inside mine. 

 

On the downside, we have a huge storm series coming to the Pacific North West and Astrospheric looks white for the next 10 days. I bet this is what the UPS truck carrying my scope looked like:

[JimTheEngineer]

Readjusted tilt and took the following frames on M31.
ASI2600MC (APS-C)
SQA85 - 408mm
Gain 100
Exp 120s
Single frame, autostretch only in PI

The guiding liked the stars from the OAG - (0.19”-0.3”)!

Edited by JimTheEngineer, 11 November 2024 - 10:34 PM.

[JimTheEngineer]

Stars looked great - very small and round to edge of APS-C sensor.

[JimTheEngineer]

HFD and Roundness using ASTAP

[JimTheEngineer]

Here is the guiding at start - 0.18”. This is about 35 deg off meredian and NOT near a pole. Got this on an AM5, ASI220mini, and Askar M54 OAG.

 

Also the final processed pic:

216 x 120s Baader UV/IR (7.2hrs last night)

40 flats

60 bias

30 darks

DSS

PI - EZ soft stretch, Photometric, SETI Astro DBE, BlurXT, NoiseXT, StarXT, Curves, Merge

Save to .jpg then image reduction to fit CN.

Edited by JimTheEngineer, 11 November 2024 - 11:18 PM.

[akdwivedi]

Received a 2nd scope. It has some smaller metal pieces on the inside rear lens. That’s the second time with the same issue. Will see if these will fall off. Also the focuser had some minor up/down movement, but you can get most of it out by tightening up the rotator lock. Also, not a big deal, but the rotator lock does not allow you to rotate the Askar OAG around it unless you add 5mm+ extension between to OAG and scope. Hopefully these metal bits drop off the rear lens shortly. Askar really needs to look at their assembly procedure to eliminate these metal shavings. Maybe blow the tube out and some QC?

First pic is rear lens right out of box with M48 adapter removed. Second is after some cleaning.

thats certainly not a good example of QA for an expensive scope. doesnt look like something that happened during transportation. I have bought from two smaller scopes from askar before and they came clean inside, perfect cosmetics and functionality.

 

you should return it and ask vendor to at least inspect the scope before shipping.

[JimTheEngineer]

I have had about 6 clear nights with this scope and have processed 8 images. This is a very nice scope. Stars are so perfect, I really don’t need blurXT or any star reduction processing. Most of the clear nights have been close to the full moon and I needed to switch to narrowband targets. I have yet to see any bad halos on bright stars. Pelican and Andromeda looked great. Need more data on Triangulum and horsehead/flame. Jellyfish, tadpole/flaming star, and Cygnus loop looked great with narrowband, but would like to see them with only UV/IR filter. Also did C2023A - DSS comet & star processing turned out much better than before using the AT60ED. Every image solving and guiding program really likes the flat field and tiny stars. The focuser has worked great. I have rotated the camera and have not seen any bad tilt at different angles. You do need to keep the rotator screw nice and snug. The focuser travel is very small at only 8,000 steps for the EAF. Focus typically varies due to temperature change about 20-30 steps max over the night with median star sizes reported to be 1.65” if focus/seeing is good and as high as 2.0” if seeing is bad. The focus routine using ASIAir Plus is set to minimum steps of 10 and I think my actual backlash is around 30-40 steps. My crops due to meredian flips is minimal. Waiting for the moon to disappear so I can see how it handles the Pleiades. This scope is definitely a keeper and 408mm is a perfect focal length for wide field targets like andromeda I can’t get at 2438mm focal length. Planning to take this to Big Bend in the next couple months to see what a proper dark site can do…

[akdwivedi]

thats a much more positive review. I guess the focuser travel is short due to it being a astrograph and not intended to be used for visual purpose unlike fsq85.

[JimTheEngineer]

Nice detail using the SQA85, ASI2600MC, 10hrs data, 3min EXP, 250 gain, Optolong Ultimate, Nov 14,15,19,20,21 (full moon) on Cygnus Loop.

Edited by JimTheEngineer, 24 November 2024 - 11:57 AM.

[JimTheEngineer]

Had an offline question about whether an electronic rotator would fit. I don’t own one, but thought I would post some photos with measurements. You would probably need a special made adapter. Hope this helps.

[JimTheEngineer]

It should be noted the silver threads on the rear end of rotator are NOT the same as the black threads on the front end of the rotator. It also looks like the black threads is a 21mm long threaded tube (nipple) that screws into the rotator. However, I am not sure it can be removed.

Edited by JimTheEngineer, 26 November 2024 - 12:06 PM.

[JimTheEngineer]

On the silver side of the rotator, there are 3 adapters provided by Askar that are 7mm in optical length that go to M42, M48, and M54.

Edited by JimTheEngineer, 26 November 2024 - 11:58 AM.

[JimTheEngineer]

Here is another nice pic of Triangulum using the SQA85, ASI2600MC, 10hrs data, 3min EXP, 100 gain, No Filter, Nov 11, 22-25. Stars and details are great. This one is cropped since I had sort of a 45deg rotation on frames taken on Nov 11.

Edited by JimTheEngineer, 26 November 2024 - 04:13 PM.

[Apennine]

Had an offline question about whether an electronic rotator would fit. I don’t own one, but thought I would post some photos with measurements. You would probably need a special made adapter. Hope this helps.

I believe Askar also provides an M68 adapter with the SQA85, mine did at least. I have used that adapter screwed directly into the Pegasus Falcon V2 rotator (also M68), then adapted to M42 for my 36mm EFW. This works well, with the manual rotator ahead of the electronic rotator allowing for positioning its orientation. With this setup, I have to rack out about 10mm to achieve focus, so not much. The only draw back is I could not use an OAG, there is not enough room.

I have verified the great performance of this scope, but too cloudy so far for any real imaging.

[JimTheEngineer]

Apennine is correct and I was not. The adapters off the rear end of the rotator supplied by Askar are M48, M54, and M68.

Also, the rear lens is shown. The optical path ID is only 40mm at this point, but as you move a sheet of paper back away from the rear lens, the image circle gets bigger. I would bet it easily covers at least a 44mm image circle. However, I am still wondering if you install a 10mm OAG prism so there is no shadow on a full frame sensor, whether you get an entire field of stars on a 174mini guide sensor using the Askar OAG. Hope we eventually see some uncropped full frame unprocessed photos from someone with the scope and full frame camera.

Certainly the APS-C with a smaller 220mini guider is fully covered and I am impressed with the images, the guiding due to perfect stars, and the speed in which various program can plate solve and not really need any post processing of the stars…

Edited by JimTheEngineer, 26 November 2024 - 05:11 PM.

[charles.tremblay.darveau]

It's useful to know you can remove the stock rotator, so you can free up precious backfocus space for an electronic rotator. Would good to know from sharpstar/askar what the thread spec is.

[sharpstar-service]

Hello，

The thread of the rotator removed is M74*1