Autoguider Troubleshooting 12″ OS

8th April 2023

After a successful morning of Luke helping me rewire the 12″ due to the removal of all computers apart from the Mac Mini, I looked at why the guider kept disconnecting last night and then not calibrating. It transpired to be the length of the USB run. I was hoping through 3 hubs and many meters of cable. On replacing the cable with a shorter one and plugging it into a single hub, the connection error went away. The only thing left to do was test auto guiding at night.

So roll on evening and I went out early to catch the first starts. Luke and I had replaced the All Sky Camera during the day so we wanted to see what that looked like, It is fair to say the ZWO ASI178MC is an amazing upgrade to the rubbish little ZWO ASI120MC I had been using.

New ASC with wider lens

So after much messing about with trying a camera other than the SX Lodestar, trying several pieces of software including PHD2 that I could not get working, I settled on TSX for guiding and managed to get it calibrated. On swapping the side of the mount and recalibrating I had a similar problem, however I think the brightness of the guidestar, along with the exposure time and the order I was doing things in had caused the issue.

Below are the settings used for the working system, note the calibration distance is 30 arcsecs which is fine if you calibrate on a star rather than a hot pixel.

Relay Settings including Direct Guide! 30 arc seconds for calibration distance

Successful calibration East side of mount

Successful calibration West side of mount

Guide Target Method

Settings

X2 Plugin and remove hot pixels

Autoguide tab – long exposure and subframe selected

more settings

Final settings

Success!

So you must select a bright enough star.

You must put a subframe round it.

You must them expose on that subframe.

You must then calibrate that subframe.

Viewing Report 4th April 2023

18:20 – 03:00

Before sunset I wanted to reset the dome parameters in TSX as these had got corrupted since loosing the NUC. I now have a set of working settings.

So I have managed to get the dome rotation working. The settings can be seen here for the OS12 and are documented for the other 2 scopes which are piggybacked in my TOSA manual.

OS 12″ Dome Settings

Skywatcher 120 Esprit Dome Settings

Skywatcher 5″ Dome Settings

Serial Device used for Dome

Unfortunately the night did not produce any images as the last thing I could not get working was guiding, I will take and look tomorrow. The main problem was I could get TSX, PHD2 or a 3rd party piece of software to calibrate the guider.

Imaging Report 15th-16th December 2022

As it was a work night and Dave was working I was imaging from the back garden and not the dark site. I started late in the evening and had issues sorting out the autofocus in NINA which meant I was even later than I had planned.

Using the OptoLong L-Pro filter and the native camera driver (not ASCOM) :

QHY268C Nina Native Mode

The target was decided by Dave as M31 (Andromeda Galaxy), I decided on 120 second exposures at -15℃, gain 0 and offset 30 (Photographic Mode). I finally started to capture data at 19:55 when M31 had already transited 45 minutes earlier.

M31 single sub (stretched) via NINA Imaging Session

I believe the dark shadow to the left is the QHY OAG prism, I may have to reduce it’s depth in the light path or rotate it 45 degrees so it sits on the long horizontal axis.

Once M31 had reached approximately 50 degrees altitude and was starting to set in the West my guiding started going awry especially in RA. I put this done to either balance issues or cable snagging so that’s something I need to look at in the future.

After shutting down earlier than I thought due to the guiding issue and the pending rising Moon I decided to do my darks, flats and dark flats. However my Pegasus Flatmaster refused to connect to NINA so I decided to fix and complete this task on a different day.

I only managed to capture 62 subs which totals just over 2 hours. I was hoping to get at least 6 hrs for a single session and something approaching > 12 hours which means I will need several more nights to capture my required amount of data for M31.

Not a great first outing but given I hadn’t imaged in ages this was expected. I can honestly say that although a OSC coupled with the new harmonic mounts such as the ZWO AM5/Pegasus Nyx are very convenient as part of a lightweight holiday travel setup. OSC also is easier processing but still I can say I’m not a total fan due to the loss of high frequency data, high HFR focus issues and in the case of the QHY268C the noise banding issue which although appears to be removed by darks etc still is unnerving.

Update (17/12/2022)

Have resolved my Flatmaster 120 panel issues but I feel I’m better off with a fully controllable fixed panel instead of a manual panel so I will look into that.

My Darks, Flats and Dark Flats are now done (25 of each) all performed at -15℃ to match this session temperatures but there is still not enough actual data to start processing.

Equipment Check-up

So after ages I’m planning to perform some imaging after being challenged by Dave to produce a OSC image of M31 with the QHY268C that can be of print quality.

The first step was upgrading all the necessary software to make sure both the NUC and laptop would not be interrupted during my planned imaging session.

  • Windows10 latest Updates (Dec2022)
  • SGPro (4.2.0936)
  • NINA (2.1 HF1 Beta002)
  • ASTAP (2022.12.09)
  • ASCOM (6.6SP1)
  • Pegasus Ultimate PowerBox (1.6.1230.46)
  • iOptron commander (5.9.0.2)

The iOptron CEM60 mount hadn’t been updated in ages and it showed :

  • HandControllerV2 : 210106
  • MainBoard : 190716
  • RA board : 201005
  • DEC board : 190716

After performing the firmware update procedure, the mount was now showing the following levels :

  • HandControllerV2 : 220119
  • MainBoard : 211018
  • RA board : 211018
  • DEC board : 211018
  • Catalog : 150429

Of course I will need to perform a new zero mount position following the upgrade. Tonight I will also be changing the OpenPHD algorithm to PredictivePEC as described by Cuiv the LazyGeek :

https://www.youtube.com/watch?v=BfvmlR3It1o

Viewing Report 10th December 2022

23:00 – 00:20

So it’s about time I tried to find a replacement for SGPro, given the continued problems with it, it’s less than intuitive design and find something that does not cause friction in my desire to capture more photons from the distant universe! So after looking at NINA briefly earlier this year, I have gone for it this evening to see if I can indeed capture some images.

The problem that set me back once before with NINA was the lack of connection to the FLI focuser. I just simply got an ASCOM error (I really dislike ASCOM). So after some educated guessing I got it connected. Instead of connecting to the FLI focuser directly I actually went through ASCOM which bizarrely cured the error.

With that done. I could now run autofocus, and only the 2nd time in my life this astronomy programme focused on the first go. The only other piece of software that good is the ZWO ASIAIR that I really enjoy because it just works.

I have now connected NINA to PHD2, also to TSX and left TSX to control the dome. I may change this later, however it works just fine and has not caused any problems. The only reason may be to further automate the dome for closing and reporting on status if that is a feature of NINA, something to look into later.

NINA at work

Managed to take 5 or 6 Ha images of 600s this evening before the cloud rolled in. I can use the flats from yesterday. A good evening testing given conditions including the almost full but waining Moon.

Exoplanet HAT-P-32b (14/9/2020) – IMT3

So the evening started well, I had logged into IMT3, got the dome ready, TheSkyX/SGPro software was up and running, CMOS camera was cooled and I was already syncing on a bright star even though it was still twilight.

Dave and I had chatted the previous night and had settled on HAT-P-32b in the constellation of Andromeda. The reason was due to the target position in the sky, the time of rising and setting was before the rise of the sun so we could get a full ingress and egress and no meridian flip was required.

Then the gremlins started to play havoc with our efforts and I was having major issue with guiding to the point that I was going to give up as the issues were eating into the desired 1 hour egress monitoring time period. Dave joined the session to help resolve the issue and we managed to start imaging about 10 minutes before the start of the transit.

Dave had to go to bed due to work commitments but I was determined to get the full set of observation and run it through the HOPS analysis software. It was an uneventful night interspaced with music, movies and hot cups of tea.

Once I had transferred the data over the internet to my server, performed the analysis and sent the result to Dave it was 5:30am so I crawled into bed around 6am.

Detrended Model from HOPS software

Exoplanet WASP-93b (1-2/8/2020) – IMT3

Session time 21:00 (1/8) – 03:41 (2/8)

@ 19:00 Opened dome in order to cool the dome and scope down.

@ 21:00 GingerGeek arrives, wine is poured and we took 5 x darks, flats and bias for both the last run and tonight. The flats (red) were 3 seconds exposure to get 2/3 well depth required for this.

@ 21:44 Slewed to WASP-93b before we set about focusing on a nearby magnitude 5 star using the Red filter. Starting focus position was 58841@19.42℃.

@ 22:06 After failing to focus using the Red filter we resorted to using the Luminance filter to auto focus and achieved a excellent fit (focus position 61630, HFR 4.95 @20.83℃).

When we swapped back to the Red filter, SGPro then moved the filter offset to focuser position 60630. We slewed back to WASP-93b (GSC:3261:1703) and found a guide star just off centre of the star field with the exoplanet target.

Started to take exposures to find the brightest value of the centre pixel of the star and make sure it was 2/3 full well depth and thus 33,000 ADU (even though it is a 12-bit camera SGPro is set to 16-bit for ease of use. Eventually this was achieved at around 200 second exposure.

@ 22:51 Started imaging, 18.21℃ was measured at the focuser.

Frame and focus of starfield
Target star for Exoplanet measurements
Local conditions
200s exposure of starfield
Another plane!
Target location in Cassiopeia
Details of WASP-93b transit for tonight
Some cloud early on in the night

Mars imaging finished at 03:41

Viewing Report 2nd June 2020 – IMT3

20:28 – 00:30

After a day of checking the mount and spending some 3 hours resetting the RA and DEC cam stop and spring plungers I have come out to see if I have resolved the image or made it worse. I can still hear the squeaking of the cables in the Through the mount position as the worm turns so I do need to remove 1 or 2 of them to free it up. However I no longer hear the knocking, tapping and grinding of the Dec axis. I am also going to capture some PEC data for Tom on the Software Bisque forum to look at. GingerGeek with his usual smoking jacket turned up to assist from a distance.

Whilst trying to find a star we came across a galaxy, NGC 5646 H126-1, which looked very interesting for the 12″, so we will come back and image that at a later date. We are in a rush for the clouds as it is to cloud over by 11:30pm. What we need to do is disable PEC, disable TPoint and Protrack and the guider relays then point at a star and guide without applying any corrections as per page 147 of the MEII manual for 15 minutes.

I went out to the dome and set with the help of GingerGeek the camera on the back of the 12″ to as close to 0 degrees as possible, in our case 0.81 degrees after plate solving.

We slewed to a start neat declination 0 and close to the Meridian on the East side of the mount called Tycho 326:747 and at 22:37 started to look at the auto-guider settings. The star was at DEC +01Β° 34′ 10.909″ and RA 14h 45m 20.1920. The auto-guider log in question for tonight was “Autoguider.018.log”. The star looked good in the main ZWO ASI1600mm camera which we would use to guide and collect the data. We did notice as per the image below over 15 minutes the star drifting East, so the polar alignment is out. More importantly we got the 15 minutes of data in the log as the clouds started to roll in, as can be seen in the star brightness below.

Autoguiding in TSX

The resulting log file was read into the Sky’s PEC and the raw data shown below one we clicked ‘Fit’ on the data which scales it to this chart. The peak to peak was 0.7 arcsecs. We applied this to the mount –

Raw PEC data from log
Fitted and applied PEC data

Next whilst GingerGeek went off to get his beauty sleep…..he really needs it πŸ™‚ I set about slewing to a bright star in the vicinity and calibrating the guider, since I had rotated the camera. The calibration was successful even though the RA looked slights odd as a fit. The different in the RA and Dec rate was potentially due to position on the sky and the error in the RA plotting data. I will go back and do another calibration next time it is clear.

Calibration in PHD2

I then slewed to M92, could not find a guide star very suitable so moved around a bit and then started to guide and see what the graph looked like. What surprised me was the the amplitude of the guiding was only 0.36 arcsecs which is really low and no guiding issues as I saw before. It looks like the adjustments to the spring plungers and cam stops may have been the cause and fix.

Guiding graph at +74 deg altitude and near M92

I performed a quick focus run whilst pausing the guiding and got 61836 and HFR 4.4 which is vert good for this scope.

Auto focus

Meanwhile the clouds from the North had started to drift in which was going to stop play πŸ™

All Sky Camera

I managed to get a single frame and focus on M92 of 20s before the clouds stopped the guiding. So I shut up the dome, sent the logs to Software Bisque, or the chap on the forum who was kind enough to help and went off to bed.

M92 20s sub

Viewing Report 1st June 2020 – IMT3

20:25 – 00:15

Dome once again open to cool down

Solved FoV for Lodestar guider on 12″

Now guiding on star to West side of mount around 0 degrees Dec and near the Meridian to see if problem reoccurs, graph looks ok but there is a slight regular pattern of error.

Slewed to M92 which is a glob currently at Alt +74, Dec 43 and on the East side of the mount where I had issues last night. I plate solved the image.

The auto focus run looked good

Found guide star by moving M92 slightly off centre. Now guiding. All looked good for a short while. So each section of PHD2 graph is 25 points, so when you have 100 points selected there are 4 sections of the graph. This mean each section/column represents own my case 250 seconds as I expose for 10 seconds, so just over 4 minutes per section. So the errors I saw last night were about 12mins apart. This cannot be the work gear as it has a cycle of 2min 29sec. This is from the latest Paramount manual for the MEII.

  • Tracking at the sidereal rate, one revolution of the worm takes 149.6 seconds (2 minutes 29 seconds).
  • The right ascension gear has 576 teeth.
  • The declination gear has 475 teeth.

The error I am seeing is about 4mins. I cannot continue imaging as every few frames are trailed.

Viewing Report 31st May 2020 – IMT3

18:01 – 01:09

Opened dome early to cool down at 6pm.

The first thing to do were Flats for Ha first for the previous night but also for use tonight. I completed this at 22:15

At 22:31 I performed focus run on Luminance which came in at position 59841 with HFR 4.77.

I started an image run as soon as the Pelican Nebula (IC5067) was above the neighbours house. I have set a run of 10 x 600s and 20 x 300s Ha subs guided with the new PHD2 settings to prove the 12″ now works from 1 night to another. Then we can try the Esprit on the next clear night. The guiding at first looked okay.

Good initial guiding

The resulting image looked very good too

300s Ha guided Pelican
300s Ha guided zoomed no trailing
600s Ha Pelican guided
600s guided zoomed no trailing

After about 5 frames I suddenly ran into a problem the guiding looked like this

There were large movements in the Dec and the RA would not return to centre. Soon enough SGPro stopped imaging and tried to settle the guider and then further complained about not being able to settle. So I temporarily changed the Hysterisis from 10 to 15 to see if this would get the star back. It did, well just.

The RA axis returns to the centre after quite some time. Is this possibly seeing related or is there something mechanical amiss with the setup?

I did notice the problem one more and then went off to bed left it running 01:09 leaving the possible bump in the worm to resolve itself.

bump in the worm?

Addendum – So got up this morning and the scope had continued its travel across the heavens. I looked at SGPro and it finished the sequence without any problem. I then looked at PHD2 and expanded the time to include the maximum span possible as it had been trying to guide after loosing the star (I have check boxed Enable Star Mass Detection in the hope this fixes it) and I noticed a problem, which is the recurring South then North oscillation which I now need to investigate as that is the cause of loosing an image due to the star moving. It looks for all the world to be on the worm gear. I will set about measuring the PEC tonight and see if I can see it. It may of course be from when I adjusted the work due to another problem I had and it may not be quite right. I will also ask on the forum.

Viewing Report 30th May 2020 – IMT3

5pm – 3:19am

I opened the dome at 5pm. I wanted to try tonight to sort guiding via PHD2 again on the 12″ this evening and then on Esprit120 if enough time allowed.

I changed the PHD2 Profile for 12″ from 6 calibration steps to 12. Performed calibration. Started test guiding in West at +47 Alt. Tried 300 seconds exposure x2 all good

I Slewed back to the East and to Pelican Nebula. Set the Reverse Dec Output After Meridian Flip tick box again ! It then re-calibrated for this side of the mount.

I have also changed the assume Dec orthogonal to the RA axis.

I reran the calibration a number of times until there was no longer an error at the end of the calibration. There was also trailing of stars. Some of the problem seems to have been an incorrect calibration, we need the RA and DEC rates to be very close indeed. Some of ours this evening were 1.5 arcsec difference. The good calibration we finally settled on was 0.5 arcsec difference. The other change was I went out and tightened up the grub screw holding the Lodestar guider on the prism tube that goes into the OAG body, this was loose and I could move the back end of the guider around. This was due to changing the OAG position recently and clearly not tightening the grub screw in enough.

Good calibration
Good guiding after good calibration

I then refocused on Lum and then switched to Ha. This is the image after 300s with a much better HFR of 5.21

Pelican 300s in focus with no trailed stars
Close up of stars from 300s image

When I had a bump in the seeing (assumed) the PHD2 graph looked like this

PHD2 graph bump in seeing

the resulting image of 300s I was in the middle of looked like this :

Image effected by seeing and bump in PHD2 graph

and zoomed in you can see the problem.

Trailed stars due to that seeing bump

Watching Chris Woodhouse’s excellent YouTube video on PHD2 guiding he has also set the min star size to stop it picking up a hot pixel, something we have seen this evening. He has also disabled Star Mass Detection, which stops PHD restarting if it if it thinks another star has been picked even though it may not have, both of these under the brain and guiding tab.

Settings before the change
Minimum star HFD and Star Mass Detection changes

It’s now 2:51am, the sky is brightening but the seeing has settled, the mount is behaving and I am taking 600s Ha images of the Pelican Nebula without any trailing of stars. The odd spike sees a jump up to 3 arcsecs occasionally.

600s Pelican in Ha with good guiding
Close up view of stars at 600s

The guiding graph below shows a really good small RMS below 1 which is key.

PHD good guiding below 1 RMS

So by 3:19am the sky is really getting bright and showing on the SQM as 18.6 and dropping fast. I have stopped guiding and imaging and will now head to bed. The final focus position for Ha was 59925 so I can grab flats tomorrow! I will then take a look at the Esprit120 tomorrow night.

Viewing Report 29th May 2020 – IMT3

21:05 -2:56am

Currently cooling dome since 8pm.

Dome open to cool down

Logged in at 22:43 to slew to Pelican IC 5067

Esprit 120 FHR was 1.99 for Lum and 2.54 on the Ha

Focused on Deneb , 30 seconds exposure produced HFR 2.23

Deneb – 30 seconds in Ha
Solve and Sync

Solve and sync completed on Deneb in Ha

The focus point for Ha was 6217

Now for a quick frame and focus, 30 seconds exposure

30 seconds Ha on Pelican as Frame and Focus test

That looked good, next up was to see if we can image for 5 minutes unguided and see what the resulting image looked like

300s Ha Pelican

Again the resulting image looked very good and no star trails

Clear skies with -18℃ measured by the Infrared sensor on the AAG Cloud-Watcher.

AAG Infrared sensor read -18c so zero clouds

I then tried a 10min image but got clear trailing.

Star trailing at 10 minute exposure

So I set the guiding up with PHD2, went out to the dome and created a dark library as this was not done. I then set about training the guider and then set it running, initially with a 4 second exposure. The resulting guide graph looked a bit bumpy. The ASC looked very clear this evening which was the first time in a while. You could see stars to the left hand edge of the image which is normally obscured by cloud.

ASC Clear skies

We decided to run the guiding assistant in PHD2 and see if there were any changes that needed to be made. It came up with some suggestions including redoing the calibration and changing the calibration step size from 1600 to allow more steps in the calibration, in this case I changed to 1200 to try and go from 3 steps per axis to 8, however I got to 6 steps and this seemed good enough. When I then reran the guiding assistant I no long got the error about calibration. I did have a few suggestions as seen below which I applied.

Guiding Assistant recommendations

So the changes made still have not allowed 10mins images, they are still trailed. So that I do not waste any further time this evening I captured 5 minute images instead of 10 minutes and I will relook at the guiding next week when the Moon get brigheter.

At 1:38 we gave up on guiding and switched to 12″, Autofocus on Lum, 63384 HFR 5.4. Took some 5 minute and a single 10 minute frame guided, scope trailing ?

There were three scopes on the Pelican Nebula (IC5070/IC5067) tonight as GingerGeek was imaging with the Tak FSQ85 from his back garden.

3 Different image scales from tonight

Finished to go to bed at 2:56 am, GingerGeek finished the session by taking flats, warming up the CCD and bringing the scope indoors just after 3am.

Rough stack of Ha (5nm) 10×600 seconds, -15℃ From the FSQ85
ASC and Summer Triangle

Viewing Report 26th May 2020 – IMT3

21:00 – 00:46

All Sky Camera

Opened dome at 4pm to start cooling the 12″, but actually started to play by looking at guider on the 12″ at 9pm. The guider had never really produced round stars and I suspected this was due to it not being pushed all the way in, far enough to be in the sweet spot for focus.

So I took off and adjusted with a spacer of which I had many in different thicknesses. I found the ideal one to fit that would allow the filter wheel Now round stars. Given high cloud I have set running on M5 LRGB, 60 x 60 seconds L / 30 x 60s RGB. Not guiding. Gain 139 Offset 21. Cooler -15. to rotate far enough that it did not fowl the guide camera, which until now it had. Now this was done, it was time to test.

Round guider stars

The images were much better, the stars tight and round. I also changed the rotation of the guider so that its chip was square to the rectangular whole in the light pickoff shaft.

Stretched M5

So now that was achieved I went off to image M5, but without the guider as I could not find a guide star……..typical. I chose M5 as we have some frames from a previous night in May but focus was not as good as tonight and the ADU was too high. I left the scope running 60 x Luminance and 30 x RGB and went to bed.

Images captured for M5

Addendum. The dome shut when the Sun started to rise which is fantastic and working as designed. What is not is the AAG must have hung and although I could see in Windows Task Manager it was nowhere to be seen, not in the icon tray or open as a window. Also I forgot to keep the dome log open in TSX so could not see the time stamp of closure. I will have a check list for the next night out. Also I now realise the pick off mirror obscuring the corner of the camera chip for the main camera so I need to either move where the light is picked off from or move the mirror out slightly without effecting the focus.

OAG Pick off mirror obscuring main camera in corner

I have also now started to process the image and on close inspection to the frames I can see the cloud moving across in the Red channel. Here is the results for the processed image.

M5 Cropped

Viewing Report 15th May 2020 – IMT3

21:58 – 02:02

Just setting up for an imaging run and to test imaging without temp compensation to see if the 12″ keeps focus without it. I started by myself then was joining by GingerGeek and then Bob.

Performed a SGPro autofocus run on Mag 7 star produced focus position of 71,828 @ 4.6 HFR at 14.47℃.

1st autofocus run
Resulting M98 image from 1st autofocus run

The resulting image was good with good star shapes. Although I suspected at this point the seeing was not excellent.

I let the sequence run for a bit imaging M98 through LRGB and then decided the HFR was gradually getting larger so I performed a 2nd Autofocus run which came in at position 72,215 HFR 5.7 at 13.97℃.

Again I let the sequence continue for at least 4 images and the performed another Autofocus run, note all the time this was on M98 and not slewing away to another star. This came in at focus position 72,697 @HFR 5.7 at 13.82℃.

I continued this routine again and performed another Autofocus run on M98 focus position 73,441 HFR 5.4 at 12.98℃.

I then decided, due to struggling to get a good HFR on focus runs to see if the autofocus was introducing an issue so I changed the autofocus setting from 9 data points to 11 data points to try and get fuller deeper curve. The resulting curve was better and more complete on both sides of the U shape. I then imaged further and then attempted an autofocus with the settings change for the step size from 2500 to 1500 and data points from 11 to 15. This was because I felt we always have a flatfish bottom to the autofocus which at this focal length of 2.5m shows the quality of the seeing with a narrower flat bottom being better seeing. The new autofocus came in at position 73,534 HFR 5.1 at 12.66℃. Meanwhile we kept noticing satellites going across the ASC which I now believe are potentially StarLink so very annoying.

ASC with Satellite

The new autofocus settings seem to work better. Anything less than 1500 step size would be less than the seeing, as proved tonight so I may find that 2000 is ideal, a test for another night. Also noted that Red filter was showing the worst HFR changes due to seeing and humidity was around 75%, again worthy of note to see how good the seeing is. The guiding was all over the place tonight, again another indicator of poor seeing. So all these things are not poor setup or poor software but poor seeing!

This I believe was the ISS going over captured in the ASC.

ASC and ISS

I was really pleased GingerGeek and I had spent time a week or so ago when the Moon was around working out the location of the Field of View (FoV) indicator on TSX, it makes it much easier to find a guide star, although tonight M98 had a couple strategically placed which was great.

FoV for Off Axis Guider and the OS main camera

By 2pm the cloud had started to appear, first at South Winston with Steve’s setup, then at Mil Dave’s at Tadley and finally here some 15 minutes later. The guide star was lost by PHD and SGPro in a well ordered fashion did what it is really good at and stopped imaging.

SGPro can’t continue imaging due to guide star loss πŸ™‚
PHD2 and guide star loss due to cloud

Here is where I got up to so LRGB on M98 for the night with 15 x Luminance and 12 x Red, Green and Blue was the original first image for each was there wrong exposure time, so RGB at 2mins and Luminance at 5mins. Very happy for an evening testing and gathering data at the same time.

Here is a set of image statistics charts for each filter for the HFR changing over the evening whilst I refocused. Next time I will focus once and not refocus and see what happens with the temperature drop.

Final look at the AAG weather station as the cloud sensor which is Infrared makes the dome unsafe and shuts it.

AAG Weather Station now Cloudy

Here is the final view from the ASC

ASC and cloud

and of course to finish the evening off another satellite!

Viewing Report – Cinco de Mayo 2020

Moon 96% Waning.

Our TOSA Manual needs updating now that we have replaced the HiTechAstro Deluxe Cloud Sensor with the LunΓ‘tico AAG CloudWatcher cloud detector.

New Screens to get familiar with:

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Initially I was unable to open the shutter of the dome. Thinking I’d forgotten to reset the HiTechAstro relay I soon realised I had to figure out why the AAG_Cloudwatcher software was reporting Unsafe. GingerGeek spotted that the Brightness level looked like a sawtooth and should settle after a few minutes, which it appeared to do and the dome shutter opened successfully.

Following on from my previous observing session on 1st May when clouds interrupted play just as I was completing a Guiding Assistant run in PHD2, I started tonight’s session with a quick look at Venus before it set below our horizon and then had another go at running the Guiding Assistant in PHD2 for the OS 12″ / Tak FS-102 combination, with the Tak as the guider for the Officina Stellare.

Venus in Ha (because it’s so bright).

Crop

As the Tak has an Alnitak Flip Flat attached to it I added it to the profile I’ve created for the OS12 and Tak combination so that the panel can be opened to allow light through to the camera πŸ™‚

Guiding Assistant completed successfully and values applied for RA MnMo, Dec MnMo and Dec Backlash compensation.

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Y scale = 2, Target Radius = 1.5

Sequence running for 2, 5, 7, 10, 12 and 15minutes.

2, 5,& 7 minutes exposures ok but trailing beginning to show at 10 minutes, quite evident at 12 minutes and very evident at 15 minutes.

Added 8 and 9 minutes to sequence, but both of these show signs of stars trailing.

Started a sequence of 24 x 5 minute exposures.

Aborted at frame 20 as the NGC3628 was now below the horizon.

The image has drifted and NGC 3628 has not remained fixed in the frame, so we still have issues with guiding as that is almost certainly the source of the drift.

02:22 Slew to M5, just off centre.

Slew to HIP 74975 to centre and focus.

De-selected guider.

02:57 Slewed to M5 and started a sequence of 24 x Lum and 8 x R,G,B 120s frames.

Sample Luminance frame:

04:08 SQM graph has started to droop. Was 18.2 before 4am, now down to 18

04:10 ASC image brightening quickly

04:15 SQM 17.54

04:24 Camera Warming Up

Disconnected Guider

Telescope Parked and disconnected.

Dome Parked (shutter closed) and disconnected

De-humidifier on.

Camera Power Off

04:30 I’m off to bed

Viewing Report 20th April 2020 – IMT3

Viewing time period – 20:15 – 23:46

TONIGHTS TARGETS

H56-1 / NGC2903-OS-Ha-300s x 12 – Done

NGC3395-OS-Ha-300s x 24 – no Ha so aborted

M94-OS-Ha-300s x 8 – Done

M85-OS-Ha-300s x 24 – no Ha so ignoring

Flats () Darks () FlatDarks ()

Camera Temp -26℃

WORKFLOW

  1. Cool down scope and dome – done
  2. Turn off Dehumidifier – done
  3. Turn off fans on scope – done
  4. Find home – done
  5. Slew to nearby star to target – done
  6. Select filter and focus – done 74,517 Ha – done
  7. Slew to target and take a test image using Frame and Focus – done
  8. Solve and Sync and then right mouse click on object and Slew Here – done
  9. Setup SGPro Sequence with details – done
  10. Make sure guider connected and calibrate – done
  11. When guiding run sequence – done

Tonight we will take a bunch of Ha images for 4 targets we have been imaging recently with Ha data being provided through the 12″. I have selected the 4 objects in order of passing across the Meridian first. We should aim to get 2hrs of Ha in each, in which case we may need to take the rest tomorrow.

Auto focus run before dark on Ha using 20s subs @ 21:00 focus position is now 74,517 at focuser temp 15.84℃

Autofocus on Ha

Autoguiding on 10s with one of the 2 stars in the FoV of the guider for OS12.

@21:17 started taking the first image. Noticed quickly the guiding in Dec went up, so stopped and recalibrated guider. Then started guiding on 8 second subs.

Guiding 8s OS12 Lodestar

So the sequence is now running and taking frames of the first target in Ha NGC2903 aka H56-1.

H56-1 / NGC2903 Ha 300s

After 12 x 300 seconds on NGC2903 I slewed to NGC3395 and took the first Ha image, but unfortunately it was very dim so not worth pursuing. Instead I have now switched to M94 which is currently on the East side of the Meridian. I will take 24 x 300 seconds Ha with no guiding. It will require a meridian flip in about 90 minutes. I will then leave Bob to complete the Ha on M94 for the rest of the night as M85 does not have any Ha within it.

Bob continued and had a little success, cloud rolled in at 23:46 so frame 9 onwards are no good so we got 8 frames in total for M94, we will continue another night. The shutter was closed as Bob did the meridian flip due to cloud.

I tried to take calibration frames the following day at 7pm when the outside temp was 15.5℃, the inside was 18.5℃ but the ASI camera on the OS12 would not get lower than -25℃. I now concur for with Bob and GingerGeek that we should lower the cooling temp to -20℃ for the remainder of the Spring and Summer returning to closer to -30℃ in the Autumn / Winter. For now I had to wait for the temperature to drop outside and thus inside to cool down the final 1℃ to take the calibration frames. By 20:22 the temp outside had dropped to 12℃ and the internal temp to 15.8℃ which was enough to cool the camera to -26℃.

Viewing Report 19th April 2020 – IMT3

Viewing time period – 21:16 – 23:24

So first I could not see any USB devices that were plugged in to the USB hub on the mount. A reboot of the mount fixed that problem. Next I could not auto focus, I did not get to the bottom of that so tried to focus manually best I could. Then PHD2 settings were wrong for the OS12 and the associated lodestar guider, the calibration steps were 100 rather than 400, the min move was 0.66 rather than 0.18. I had taken screen shots before on the blog so changed them back, I am not sure why they have changed. I then managed to calibrate the guider on the OS12, given I have taken off the camera to clean the filters the other day.

@22:15 I started imaging RGB on M94 on the OS12.

M94 5min Red

The guiding was not bad after calibration. I set to expose once every 8 seconds on the only guide star in the FoV.

Guiding with PHD2

What I do need to do is set the FoV indicator in TSX for the Lodestar guider to the correct position to help find a guide star. Else I really should try to guide with one of the other scopes. I am now off to bed, I will leave the scope collecting the rest of the green, 2 left and the final 12 blue. Then Bob will take over imaging for the rest of the night.

Bob took over Green which lost the guide star, so he performed a meridian flip, continued on the Green and then took some Blue. Bob then took some HA, OIII, SII at 5 and 10 minutes for a test. The Ha would be useful for the galaxy as an LRGBHa image. Bob turned in at 2:50am.

M94 10min Ha

I also noticed this morning that the Offset was wrong in the ASI camera profile which was called ZWO camera in the dropdown and in fact was set to 50 rather than 21 for this Gain which was correctly set at 139. I have also changed the OSA12 No Guider profile to use the ASI2 camera rather than the ZWO one, not sure the difference. I have adjusted the setting back to 21 so all the OS12 profiles now use Gain 139 Offset 21 as their standard. If we want the other 2 setting that need changing for each time we run, along with subsequent darks and flats etc would be Gain 0 Offset 10 and Gain 75 Offset 12. For the moment the Darks and Flats etc from last night are Offset 50 so we can only use for last nights images.

Viewing Report 22nd March 2020 – Travel Scope

Viewing time period – 19:33 – 05:12

Once again unto the darkness ……….

I started setting up before dusk and the scope was ready for my on the patio once darkness had fallen. The first thing to do was use Polemaster to get the polar alignment roughly done.

Polemaster prior to alignment

@19:43 finished Polar alignment and started PHD2 drift alignement

Drift alignment for the azimuth

@20:07 finished drift aligning in Dec

@20:23 after doing the washing up I am now back to do the drift alignment of the altitude

Drift alignment altitude

@20:29 finished drift alignment in the altitude and did not need to adjust

@20:43 slewed to M35 and set the camera temp -25℃ and its running at 40%. I have set Gain to 7 and Offset to 30

I then joined the BAS Zoom call along with many others from the society. I shared my screen and explained the problem I was having that the DEC axis was still drifting. Mil Dave took me through the settings and it transpired that I had the Dec Guide Mode set to North rather than Auto. This meant it was not correcting for the error as it drifted South., I set to Auto and PHD started to correct! It now works πŸ™‚ Thanks Mil Dave!

PHD Dec Guide Mode Setting to Auto!!!!!!!!@

@21:20 I had started gathering 5min exposures of M35

Quick stack and stretch and plate solve and annotation of M35

@23:00 finished capturing M35 now waiting for M65 Trio in Leo to go across the meridian

The SkyX Trio in Leo

@23:46 started imaging Trio in Leo although there is some high level cloud

PHD Guiding now fixed πŸ™‚

MUST REMEMBER TO TAKE FLATS TOMORROW!

Viewing Report 3rd March 2020 – Travel Scope

Viewing time period – 19:37 – 22:35

Back out again tonight for a short period to look at guiding again. So with everything setup and a longer USB 2 cable in use I am now sitting in the warm Orangery. I will try again with the PHD2 software to guide and EzCap to acquire images from the QHY168C. I have set the Gain to 7 and Offset to 30 as previously used on my other QHY168C when used in Tenerife.

I polar aligned using PoleMaster. Then set about syncing the scope with Betelgeuse. It was only off slightly. The sync worked fine tonight. I then slewed to M35 and started the PHD2 guider software, selected a guide star and calibrated the guider. This worked well first time proving my new step size of 4 using a small ms time for the pulse worked.

Then I started guiding and very quickly realised the same problem as yesterday with DEC drift upwards. No amount of fiddling with the setting such as Hysteresis or Aggressiveness changes the constant upwards drift. I then remembered that I could calibrate the settings as the other night under Guider Assistant. I ran this made the changes but still the upward drift.

I then remembered that on the Paramount MEII in the dome I had to drift align with PHD2 to get it properly polar aligned and that PoleMaster was only good enough for short exposures or rough guiding. So I set about drift aligning.

PHD2 Drift Alignment

The first thing to note is that the polar alignment was out by a fair bit to get the accuracy I require in both azimuth and altitude. I have now adjusted both and the graph seems a lot smoother.

So in all it took me around 1 hour to drift align and just as I was about to test the clouds rolled in!

Clouds start to roll in

Viewing Report 1st March 2020 – Travel Scope

Viewing time period – 17:35 – 23:00

First time out for a very long time with the travel setup. I need to get the guiding working before the Tenerife holiday in July. I have left Bob to play with the IMT3 whilst I work through the bugs.

The challenge is at first remembering how to set everything up. I found after some effort I was actually missing a cable, it was in the black wheelie case in the garage with the laptop tent and scope daytime cover, but more about that later.

So So after finding a place on the patio where I could feed the USB cable through the Orangery window, I put the Berlebach tripod down and placed the MyT mount on top. I tightened the screws and then placed the Sky-Watcher Esprit 120 ED on top of the Versa Plate. Once in position I balanced the scope then connected the various cables, now all through the mount due to my good friend Bob making up some power connectors for me.

So I tried to guide through PHD2. There was a large wind blowing. On trying to calibrate the scope would not move. After what seemed like an hour I remembered that cable, this was again the ST4 guider cable that is needed on the Mac if you are guiding with PHD2 as there is no ASCOM. So I connected the ST4 cable and it worked.

What I could not achieve tonight was to get the guide graph behaving, it was a mess. The wind was at fault but still there were other issues, not least the slider to control the contrast of the screen was causing anything above 0.5s to become white.

Guiding a mess with PHD2

After many hours I gave up and brought the rig in. I had been using TheSkyX to slew there scope, PHD2 to guide and EzCap to connect to the QHY168C camera and take images. I will try again tomorrow night.

EzCap image of Betelgeuse