fwm891

I can't say what the Askar 120 APO's are like for visual use but I have 2 mounted as a dual set-up on my obsy mount and the optics (both 1x and the 0.8x) are superb with pin point stars right across the FoV.

+1 for the 585. I'm using the uncooled camera with my Askar 120-APO. Waiting to see if a mono version is in the pipeline...

M51  is a great target for the 585 plus lots of other galaxy's and smaller neb's.

Put me down as an opposit - photographer - visual is out for me. Tried it, got the tee shirt (didn't fit!)

What to do when you wake early! Well today I thought go for it it was gone 4 am but I managed to get the obsy open camera mounted and fired up, hoped the focus was good from the previous session as there was no time for an auto focus run. Set NINA for M27 hit slew and centre 20x 60s ... I got 5 mins before the sky got too bright.

Now its all packed away again, I've had a play with PI and it's still only half 6!

Breakfast calls....

Good session last night even with the first quarter moon high and bright.

I've stacked a mix of 120, 180 and 300 second subs total of (37) used with 6 having sat trails and being dumped.

Scope was my Askar 120 APO with an ASI 585 MC (uncooled) camera, Baader UVIR cut filter on an iOptron CEM 60 mount guided via PHD 2 and a TS 80mm guidescope piggy backed on the 120.

Processing was done in PI.

Hope you like

Yes working fine...

Yet it can still show 100% cloud cover with a starry sky forecast...

Dakota Starry Nights reviews on YT are quite in depth for these Dobs...

Last night was the first clear night for what seems ages so I tried some imaging with the 120 rig and an ASI 585 MC (uncooled) camera on a couple of deep sky objects (M51 and M106) I kept to more common objects as they're well known making the outcome easier to judge too.

The 120 APO had it's 1x flattener fitted so working at f7. The 585 had its gain set to 252 with an offset of 25? (need the check that). UV/IR cut filter used for all exposures.

M106 13x 180 second subs. Processed in PI. Stars and background processed separately then brought back together with pixelmath I also experimented with a soft mask to help control the background/foreground balance.

M51 22x120 second subs. Processing similar to M106.

Both images reduced for display but uncropped.

Stunning Nigella stunning.

If you go to the info page on FLO's website you'l find Clearoutside 'a weather' prediction ap enter your postcode for location and it will give you your bortle number. There are other programs around but that is the simplest.

Imaged with an Askar 120 APO 13x 300s subs and processed in PI. Camera: ASI 2600MC DUO Gain 101 with offset 25.

Well done. Agree with @tomato about the redness. I would also lighten the background too that will help you bring out the tidal effects more.

Photos added as requested 👍

I have my two Askar 120 APO's on a temporary plywood non adjustable base at present really just to make sure this set-up is going to work the way I had it working "in mind's eye" to start with. (Must take some photo!s)

I have a pulsar pier with an iOptron CEM 60 on top (non EC) in a RoR back garden obsy with quite restricted skies due to buildings and trees. Long ago I had a 115 refractor which I sold and regreted selling as it walked out the door. Recently I've had problems handling my 10 newt on and off the mount so I decided to get another refractor and purchased an Askar 120APO. After 1st light with this scope I put in an order for a second, what a brilliant scope and started drawing up plans to build a platform for the pair to get them looking at the same patch of sky. Needless to say N°2 arrived before I'd built the adjustable platform so a piece of 12mm marine ply had to take it's place. I very carefully machined and planed the plywood to make it fit for purpose as possible and bolted the two tube ring assemblies on one side and a losmany plate on the other. All as parallel as I could make them.

The tube assemblies I've offset lengthwise (35mm) so the focus knobs don't clash. Dec balance was done by shifting each OTA by the same small amount until they could be left without tipping up or down and locked off. Cameras were mounted and cables attached. I was surprised I still only needed the single 9.5Kg counterweight supplied with the CEM 60 although it was right out to the full extent. I added a small 1Kg weight to bring the bigger weight in a little and use the smalller weight's movement to fine tune RA balance. The OTA's both have 1x flatteners and I have a 0.8x flattener/reducer which is the same weight as the 1x so balance should be little effected by a change over.

The cameras in use at present are an ASI 2600MC DUO and a 585MC I'm yet to work out how to get both cameras working via NINA so I'm using NINA to control the DUO/mount/guiding/dither etc as normal and ASI STUDIO to just capture images from the 585. Loosing the odd sub where dither happens during a 585's sub...

As  it's galaxy season here's a couple of 'pairs' from Friday night with this set-up as it is at present:

Well done Lee

Although not for visual I've just got a pair of Askar 120 APO's I like that (if I ever go back to visual I can remove the back end and fit a bino viewer to one...) superb optics.

7 hours ago, Stuart1971 said:

That’s a great single sub, well done and looks like a great set up..👍🏻

but for us pixel peepers there is nothing to peep as the image is much to compressed….

Attached the original fits file.

2024-03-27_04-26-29__9.80_120.00s_0002.fits

Set my alarm for 2 AM this morning but the first break in the clouds didn't arrive until after 3:30 so Met Check and the Beeb got it wrong. Anyway set-up, focused and tracked on NGC 6888 sitting east/south east for me. managed 4 subs of 120 seconds each before clouds completely swamped things but hey it's a first light with a new scope what more could I expect!

Only one sub wasn't partly clouded out so I've run with that. Captured on an ASI 2600 MC DUO, gain 101, offset 25, filter used: an Askar Ha/OIII 6nm NB. NINA used for capture, PI used for the processing of the single sub.

Specifics: RC Astro's Noise and Star Exterminate within PI otherwise just Curves transform,  SCNR and Saturation used. Original uncropped just reduced in size for display here.

Pixel peepers welcome...

1 hour ago, Vroobel said:

Did you think about a 120mm APO binoscope? 😏

No not a visual guy

Not really what the postman delivered but I collected my 2nd Askar 120 APO from PAS on Saturday and now building a framework to support the pair on my CEM60.

One will be fixed the other will have a small amount of adjustment to get them both on the same FoV..,.

I’ve had an OO VX12 OTA mounted on an iOptron CEM 60 for photography use with a coma corrector. It’s 1/10 wave optics were superb but the scope was just too big even at f4 for me so I ended up selling it. I then got a VX10 with 1/10 wave optics again superb at f4.8 so the same 1200mm fl as the VX12. Sadly at 73 I’m now having to sell the VX10 because of problems getting it on and off the mount when I want to use my RASA.

Had a 'few' (sadly few being the operative word here) nights now with the HEM 27/RASA/ASIAIR+/ASI585MC combination. (no counterweight used). I run everything off two small Celestron LifePO4 Batteries.

I've used an 8x 50mm TS guide scope with an ASI120MM guide camera mounted on the RASA's top rail for all guiding and not had any problems with finding enough suitable guide stars. I've fitted the guide scope, ASIAIR+ onto a small losmandy saddle. This I can slide up/down the RASA's top rail to fine tune the dec balance when I swap between the 585MC and the 2600MC Duo though with the Duo I guide with it's second sensor.

Guide exposures: I'm finding as most seem to find that the shorter exposure times yeald the best guide graphs and ½ sec to 1 sec being best. That via the 8x 50 guide scope is quite easy and when using a UV/IR cut filter with the Duo. Guiding at <0.5" on a good night is achieveable, circa 0.6" on an average night and around 0.8" with pooer seeing or longer exposure lengths.

Narrowband filters with the Duo (6nm Askar Ha/OIII is my narrowest at present) require 1.5 - 2 sec guide exposures but the guiding doesn't seem to stray much beyond the 0.8-1.0" with total errors showing in the range of 1.25" - 1.46". There are night when things don't go quite so well and others where things are slightly tighter which as this is a grab-n-go kit rather than a permenent set-up.

It replaces the AZ-GTi (with EQ mod) I previously had as a grab-n-go so: a) the GTi would never have carried the RASA 8. b) guiding is better given that the focal lengths used are similar.

For me the pluses:

Carries more load (bigger instruments) Currently using either:  an Altair Ascent 80 f6 Triple with x1 or x0.8 reduce/flatteners or a Celestron 8 inch RASA future: Askar 120APO

Uses the same surveyors tripod so no additional expense on supporting the mount.

Easy to PA via the ASIAIR+

GoTo's are accurate and require little extra time centering

Minuses:

Black mount makes set-up more awkward in total darkness

Azimuth adjustment knobs are small (or my finger are too big) especially if cold.

Heavier than the AZ-GTi (I do keep it on the tripod so not a major negative)

WiFi connection via handset - doesn't really worry me as when in use the handset just lays on the tripods equipment tray.

Operation:

Setting up I've found that I don't fully tighten the altitude or azimuth locking bolts but leave them 'snug'. Tight enough to take out any wobble but loose enough that adjustments can be made to the alt/az axles when doing a PA. I've not found any slackening of the bolts/machine screws during an evening. In fact the last few sessions I've not even checked the 'snugness' of the locking bolts (until just now!) and they're fine.

I've not set the slew rate to 'max' keeping it one notch down. I've not had any problems with the slews from the Home position or when it does a flip. I'd just like to keep the RASA in one piece so a few extra seconds  is worth it.

Happy with my HEM 27.

Link missing?

Managed to fit my Nikon 800E to the Askar 120 APO with its 0.8x reducer also fitted. Shot a number of subjects but I've just picked one 90 second sub from a set of M45 to process this morning.

It was apparent last night when imaging with the 800E that the throat/lens mounting flange was acting to mask the extremities all round especially the corners. Stars are still visible in these areas so perhaps I should shoot some flats and try to reduce the shadowing caused by the cameras lens mounting.

No problems with smaller APS-C formats.

Processing in PI, noise reduction only.

NGC2264 image added (6x 90 second subs) processed as above