First light tests with the TS Hypergraph 6 (a.k.a. Sharpstar 15028 HNT)

[GalaxyGael]

Just received the TS Hypergraph 6, the TS optics branded Sharpstar 15028 HNT. Hyperbolic mirror newtonian, 420 mm focal length, with 150 mm aperture, so F/2.8. 

Came packed very nicely, nothing was loose, shaky or otherwise as has been reported here and elsewhere, and has remained so since even with the scope coming in and out every night for the last 3 nights (we got lucky this week after so many weeks of clouds). It bodes well that this leap to fast scopes provided one of the best weeks of the year so far here....

Here is it mounted, a tidy size and easier than I expected to balance. Dovetail is narrower than standard losmandy, so I added a longer one with extra length adding needed rear-end weight. ASI2600 MC on board, with the black dot indicated the long side of the sensor that is top of frame. ZWO EAF added and focuser rotated to frame and balance. 

One con is the need for a large screw driver to get at an awkward place (3 of them) in order to rotate the focuser, so when M31 is imaged (soon hopefully) I hope the framing is OK. Not too keen rotating this focuser outside. A bobs knobs or captains wheel a la Takahashi would be useful here.

Corrector is flush to its recommended depth, and using 55 mm backspacing for now.

While extendable spacer and shims will take a week to arrive, I am imaging during this fine weather week regardless of the necessary tweaks, since I cannot get over the signal that comes from this scope in 180 s subs. The initial subs and stacks gave me a giddy feeling I must be honest, especially when there is room for improvement with small tweaks.

Collimation done with cheshire and sight tube, after removing the corrector to get rid of diopter, but when that occurs it just gives two crosshairs either side of where the cross hair would be, much like a parallel line reticule, where the centre is the gap between the lines. Some fine tuning might be need one I change the spacing and tilt if its there.

Onto some initial images. Must say, the psychology of 'does the newt need to be tweaked' is not there with this one, like it was my my Mak-Newt. Refractors almost never cause this 'worry', just plug and play. I look forward even more once I iron out the small niggly issue to get it best performance. Collimation is very stable so far, and so is the focus. I never had to change it yet. We will see what the winter is like.

Image 1: Double cluster in Perseus

31 x 180 s subs (~1.5 hrs). ASI 2600MC Pro, -10C, Gain 0, native UV-IR cut filter on the camera. no processing apart from HLVG for green and a crop only after stretch in APP. All data processed in Astropixel Processor.

Image 2: Collinder 399, coat hanger or Brocchi's cluster

31 x 180s subs (~1.5 hrs), -10C, Gain 0, same camera of course, HLVF only, as it came from APP.

Image 3: Cocoon nebula IC 5146

77 x 180s subs (~4 hours), -10C, Gain 100 (where there is nebula involved, I am seeing what Gain 100 will do. Gain 0 seems to work very well for star clusters and brighter targets with 50k fwc giving wonderful star colors that I could never get before as easily as this anyway). This had some noise reduction, hlvg and matchcolor boost only, small adjustments compared to the stretched stack which also surprised me. I will be experimenting with sub length and gain in due course.

Image 5 work-in-progress: NGC 7822

47 x 180s subs, -10C, Gain 100. This is a work in progress, to be continued tonight since I can image for 5 hours without meridian flip. About 20 frames were dropped last night due to moon reflections on the subs., leaving just 141 minutes integration. This is directly from APP after stretching, no processing yet.

This is also ready showing detail and no filters were used, not even a light pollution filter, just the UV-IR cut of the camera even with LED light shining down. I am exciting about natural RGB imaging without even using quad band filters to give a nice tonal range in the reds/magentas/pinks that come without any processing. 

 

 

 

So, some tweaking to do with spacing to optimize, but I am very happy. I did notice a lot of 12 point diffraction flaring on brighter stars. You will notice that half of it disappears around some star, where it looks like a coma effect and reminiscent of flaring from mirror clips in some newts, but the reduction in flaring on one side of a star coincides exactly where the light intensity falls off where vignetting starts. I will reexamine once I have spacing perfect, because it is annoying in the way it affects star shapes. I do not mind the flaring, it add to the 'pizzazz' the fast newts give to images, but half-star flares are not nice. There are twelve bright screws around the mirror cell, which is one thing I must blacken just in case. Here is a picture of the top 6 screws around the mirror cell. They are flat ended and shiny, pointing up the light path.

This one had issues with moonlight reflections in several of the frames, appearing as a green bright disc. I have made a nice light/dew shield form black yoga mat foam that is going to be used now. This scope is very sensitive to stray light reflections.

 

 

[GalaxyGael]

My bad. Can mods move this to imaging deepsky subforum please. 

[Luke Newbould]

Beautiful shots from a fantastic looking rig! 🙂 well done!

I really know what you mean about the 'does it need tweaking?' feeling, I'm glad you aren't getting it from this though!

Great job 👍

[GalaxyGael]

1 hour ago, Luke Newbould said:

Beautiful shots from a fantastic looking rig! 🙂 well done!

I really know what you mean about the 'does it need tweaking?' feeling, I'm glad you aren't getting it from this though!

Great job 👍

Thanks Luke, appreciate that.

So far so good I guess. I'm used to the tweak0need feeling though, from years on big RCs and my old favourite Mak-Newt. The collimation and focus stability from just the last 4 nights were comforting. Once I get past the honeymoon stage and tweaking, I might see what this can do with 8 hours exposure at f/2.8. A new psychology comes after moving from f/9 and f/6 to this - integration times of 2-4 hours don't feel like a finished image (but 3 hours here is theoretically 13.5 on the Mak-Newt!), but it gets really close which might be handy when good nights are separate be weeks

[Allinthehead]

Hi Colm, congratulations on those very fine first light images. You're going to have lots of fun with that fast scope. 

My gear is very similar to yours, I have the 2600 and a Tak Epsilon 160. Where in Cork are you?

Richard.

[GalaxyGael]

1 hour ago, Allinthehead said:

Hi Colm, congratulations on those very fine first light images. You're going to have lots of fun with that fast scope. 

My gear is very similar to yours, I have the 2600 and a Tak Epsilon 160. Where in Cork are you?

Richard.

Thanks Richard. I think I will like it. The Tak 160ED is a great scope, and was what I had been saving for, but rare as hens teeth to get a hold of fast. The extender option to shift to galaxy imaging and its speed would make it an all rounder for me. But I do like this hypergraph 6 quite a bit. I am in Ballincollig.

[Allinthehead]

2 minutes ago, GalaxyGael said:

but rare as hens teeth to get a hold of fast.

Indeed, I was lucky to get one so quickly. I put my name down with Telescope Austria as soon as I knew it was in the pipeline. Highly recommend them, Tommy is superb to deal with. Unfortunately FLO not an option for me anymore after Brexit.

Did you shoot these from Ballincollig? Incredible considering the light pollution you must have. I'm in East Cork near Garryvoe.

[Lee_P]

Thanks for writing this up, it looks like a very capable telescope.

[GalaxyGael]

1 hour ago, Allinthehead said:

Indeed, I was lucky to get one so quickly. I put my name down with Telescope Austria as soon as I knew it was in the pipeline. Highly recommend them, Tommy is superb to deal with. Unfortunately FLO not an option for me anymore after Brexit.

Did you shoot these from Ballincollig? Incredible considering the light pollution you must have. I'm in East Cork near Garryvoe.

Yes, I shot in the backgarden through LP and three LED streetlamps, just like this. A light you cannot see in this picture of my Mak-Newt (to the left) shines down, with another in the shot shining toward me. The only spot where I get the shadow intersection of the LED light 'venn diagram' prevents me from seeing polaris.

 

I didn't use filters of any kind to see what data this scopes pulls in (especially considering the emission spectrum of the LEDs) and try to pick targets and position in the sky as much as I can.  I used to live in the hills above macroom, basically bortle 2/3 with a full milky way every clear night in the spring and summer but I wasn't into visible spectrum imaging at the time. curious we are so close with somewhat similar setups. Your imaging setup and processing deliver very nice and naturally images too.  

[Davey-T]

Nice scope and images, I have this scope and unfortunately mine was put together by a blind man on a Friday afternoon and basically needed rebuilding to get it working which it does now, apparently TS test theirs before despatch, also using ZWO ASI2600MC plus the ZWO26OOMM with Baader 2" filter draw which I also use with the MC and Optolong LeNhance filter.
I use a Badder Varilock to set the spacing.

Do you have a ZWO Asiair Pro ? I use one and combined with an iPad it makes a really great setup, synced to mount it autofocuses, sets up guiding has a good list of targets that can be selected and GoTod then plate solves and centres them and off you go.

There is a new version of the Asiair Pro coming out that has an external WiFi aerial as that has been a source of complaints, and does away with the micro SD card that has the OS stored on it so was a bit delicate and prone to getting corrupted if shut down unexpectedly, would definitely recommend it.

Dave

[GalaxyGael]

19 minutes ago, Lee_P said:

Thanks for writing this up, it looks like a very capable telescope.

Happy to, even if some are curious about how it performs to a degree. I had read lots of information on teething issues, and there are still some simple shortcomings I think Sharpstar could have taken care of. But, it is quite something to shift from f9 or f/6 to this.

[GalaxyGael]

10 minutes ago, Davey-T said:

Nice scope and images, I have this scope and unfortunately mine was put together by a blind man on a Friday afternoon and basically needed rebuilding to get it working which it does now, apparently TS test theirs before despatch, also using ZWO ASI2600MC plus the ZWO26OOMM with Baader 2" filter draw which I also use with the MC and Optolong LeNhance filter.
I use a Badder Varilock to set the spacing.

Do you have a ZWO Asiair Pro ? I use one and combined with an iPad it makes a really great setup, synced to mount it autofocuses, sets up guiding has a good list of targets that can be selected and GoTod then plate solves and centres them and off you go.

There is a new version of the Asiair Pro coming out that has an external WiFi aerial as that has been a source of complaints, and does away with the micro SD card that has the OS stored on it so was a bit delicate and prone to getting corrupted if shut down unexpectedly, would definitely recommend it.

Dave

Thanks Dave,

I read through all your trials and tribulations while researchign this scope as a quicker-to-get option vs a Tak 160.  Your experience was one of the things I asked the contact at TS to check explicitly, along with collimation that involved making the secondary at least perfectly square to start out with - I can take care of the rest with tweaks. I got updated from the optical bench directly, which was very nice of them. I had issues with a couple of quad modified petzvals from them and they've ben very helpful and interactive with checking anything that I buy. Incidentally, sharpstar made those quads....

I notice a lot of starburst diffraction, testing to see where that comes from, as it partially disappears on stars towards the edge of the frames (giving an awful half starburst, half normal star), mapping the edges of the vignetting or the secondary mirror edge in the frame. there are 6 sets of 2 screw ends on the rim outside the primary cell, might be a culprit.

I don't use ASI Air, having been using the sequencer capability in Sharpcap for deepsky for a while now and it is very good and very stable, so didn't go back to APT since. I used to use ASTAP, Fitswork and MixinDL some years ago for IR imaging and photometry with RC scopes, but found sharpcap (like many software options out there) quite good for an OSC imager.

 

[Davey-T]

19 minutes ago, GalaxyGael said:

there are 6 sets of 2 screw ends on the rim outside the primary cell, might be a culprit.

I blacked the back of the secondary and the shiny steel circle behind it and Loctited it to the mirror as it kept coming loose when adjusting, changed the spring on the secondary for a weaker one and changed the secondary adjusting screws for dog end ones as they have flat ends that don't dig in.
Also blacked all the shiny screws etc inside the tube.
Fitted springs under the primary mirror locking screws as they had a habit of loosening themselves and need to stay put as the slightest movement on them alters the collimation.

Have to say I'm really pleased with it now and I suppose it's good that I'm now familiar with how to take it to bits and reassemble it 🤣

Dave

[Padraic M]

Nice write-up Colm, and some lovely images.

[GalaxyGael]

39 minutes ago, Davey-T said:

I blacked the back of the secondary and the shiny steel circle behind it and Loctited it to the mirror as it kept coming loose when adjusting, changed the spring on the secondary for a weaker one and changed the secondary adjusting screws for dog end ones as they have flat ends that don't dig in.
Also blacked all the shiny screws etc inside the tube.
Fitted springs under the primary mirror locking screws as they had a habit of loosening themselves and need to stay put as the slightest movement on them alters the collimation.

Have to say I'm really pleased with it now and I suppose it's good that I'm now familiar with how to take it to bits and reassemble it 🤣

Dave

Good ideas. Here is what I see in a single 180 s sub of ngc 7822 where the moon just just about overhead and to the side. A reflection likely coming from that aluminium secondary holder.

Blackening the screws is what I might do, at least to see where the secondary bright starburst comes from.

I have not had an issues to change the springs in any of the mirror holders/cells, although the primary locks do shift collimation a lot, which I why I never tighten them. I have the main mirror collimation screws between half and full tension in collimation and it holds just fine. 

True, being able to strip and build is a great skill and glad to hear that it is performing well for you now. mind you, none of that should have happened in the first place really.

[GalaxyGael]

23 minutes ago, Padraic M said:

Nice write-up Colm, and some lovely images.

Thank you Padraic

[Davey-T]

I use this for blacking stuff.

Dave

[CCD-Freak]

How well does the GEM45 handle the SS15028HNT?  I have been thinking of getting one for better portability when traveling to star parties.  I like how the combo looks with all the red and black. 🙂

My AP900 will be a tough act to follow but it is a lot to haul around.   

 

 

 

[Davey-T]

47 minutes ago, CCD-Freak said:

How well does the GEM45 handle the SS15028HNT?  I have been thinking of getting one for better portability when traveling to star parties.  I like how the combo looks with all the red and black. 🙂

My AP900 will be a tough act to follow but it is a lot to haul around.   

I'm using the Rainbow RST-135 makes for an incredibly portable setup, doesn't require balancing so just bung the Sharpstar on it and off you go.

Dave

[GalaxyGael]

2 hours ago, CCD-Freak said:

How well does the GEM45 handle the SS15028HNT?  I have been thinking of getting one for better portability when traveling to star parties.  I like how the combo looks with all the red and black. 🙂

My AP900 will be a tough act to follow but it is a lot to haul around.   

 

 

 

The GEM 45 is great, and my guiding is between 0.37 and 0.65 depending on seeing. I have pulled it completely apart to fix a belt after it got squashed causing huge guiding excursions every 12 or so minutes, and very easy to service if ever needed to.

Handles the scope perfectly, and can handle a lot more for its size, I think about 20 kg in addition to a 5kg counterweight. 

I have the unusual GEM45G, with slightly off red RA axis (they are normally the same ZWO-type red, but not mine). I has the GEM45G saddle, but without the iguider built in. So it has both vixen and losmandy options, 2 x 3A 12 V power outlets where my ASI2600 plus in, the saddle USB for the guidescope etc. So the ioptron has just one cable to the laptop. The standard GEM45 doesn't have all these, fyi. There are encoder variants too, but I am not sure of their accuracy or whether they are more like the freedom find option from skywatcher - a handy tool but not true encoders that can compensate for guiding in many cases.

That AP900 is a lovely thing. Incidentally, I am not too hot on all the black and red, which is why I have powder blue counterweights! That mount gives you a solid base and futureproofs heavier scope or multiscope setups maybe.

[GalaxyGael]

2 hours ago, Davey-T said:

I'm using the Rainbow RST-135 makes for an incredibly portable setup, doesn't require balancing so just bung the Sharpstar on it and off you go.

Dave

I was looing at these when I was talking to a colleague to who has ABB robotic arms in their labs (like in the car making industry) that have astonishing levels of precision. These Rainbow astro and Hobym look like a variation of this tech. How is the guiding and PEC, given strain wave harmonic drives can have large amplitude long period error. OK in general use? Industry that use such encoder and drives have mastered PEC, but not yet in the mount makers. They look amazing for their size. I saw a demo where someone held onto the end of a hobym, hanging freely, and it lifted the person without any strain. 

[Catanonia]

Reminds me of my days (7 years ago) when I got one of the Boren PowerNewts F2.8 (The predecessor to your scope)

Great scope and very fast, but an absolute mare to collimate and eventually lead me to giving up on astro until now due to the issues I had with mis shaped stars in the corners.

I tried everything with it and just gave up.

Now I have a new ZWO 183MC, I might try and give it a go again, if the RASA 8 will let me lift her off the mount

Anyways, awesome images, so happy you got a good one as I too have heard the horror stories about the Boren I got and expeienced and the scope you have.

Congrats and enjoy mate, welcome to the SUB F3 group

[Davey-T]

1 hour ago, GalaxyGael said:

How is the guiding and PEC,

Using it with ASIAIR Pro PHD and have left all the settings at default, haven't messed with PEC or backlash yet.

This a corner of a ZWO ASI2600MC single frame, uncalibrated, enlarged to 200%, 600sec' WO110FLT.

Guiding is fine, got a bit of tilt that I haven't sorted yet.

Dave

 

[CCD-Freak]

I am working to get the collimation dialed in before the Okie-Tex star party next month and I finally got a clear night out at my SRO dark site   The conditions were not very favorable which seems to be the norm as of late.  I tried an IDAS NB-1 filter with an ASI-1600MM-Pro for this 35 x 2 minute image of the Pelican Nebula IC 5070.  Everything is not perfectly dialed in yet but it shows that it will be a fun combo once I get everything as I want it.

 

Edited September 5, 2021 by CCD-Freak