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.


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:







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).


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.


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


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℃


  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™‚


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

Viewing Report 1st December 2019 – IMT3 Observatory

Viewing time period – 19:03 – 21:27

Tonight I wanted to get the PHD2 guiding working when doing a meridian flip without the need to calibrate. A month ago we still failed to get this done, however a little experimenting tonight and changing a single setting has corrected the problem. The setting was the ‘Reverse Dec Outputted After Meridian Flip’ one within the Guiding table of the Advanced Setup, for which I ticked and this fixed the issue.

Reverse DEC output after meridian flip needed ticking!

I then decided to try 2 objects either side of the meridian and that worked manually slewing to each and then guiding. What did not work was the slewing automatically to the object in terms of centring on the screen. It slewed to the star, I could see it on the screen, the first object Almach worked ok, but the second object, Deneb appeared on the screen but failed to centre with the error ‘ Failed to auto centre, aborting sequence’ followed by ‘ failed to centre on object with an error less than 50 pixels’. Plate solving works fine, well at least it comes back with success.

Error message failing to centre

So I tried different sets of co-ordinates from TSX including the Topocentric and 2000.0 sets. Neither made a difference, with 2000.0 data used I still got this set of errors which shows an error in pixels of more than 50 in DEC.

DEC Error when centring

So I decided it might be the very bright object I had picked, star in this case, that was causing the problem. So to further my experimentation this evening I choose two different and less bright objects, M36 and M39, once again on different sides of the Meridian. Success !!

60s uncalibrated guided M39 exposure

So after fixing this I am now happy to go off to bed early (9:30 work tomorrow) with a job well done.

60s uncalibrated guided M36 exposure

Clear Skies πŸ™‚

Viewing Report 27th/28th October 2019 – IMT3 Observatory

Viewing time period – 19:01 – 00:05

GingerGeek and I tried to sort a few things last night, namely PHD2 guiding on both sides of the mount without any recalibration, automated meridian flip within SGPro, focusing and plate solving. After nearly 2 hours we had not fixed any of these problems. So we need further research/reading to resolve.

Instead @9pm I decided to take some more images of M76 since it was due to be fairly clear all night. What I found was this was quite simple to now setup and get working as long as I did not mind performing a manual flip at 11:30pm.

There was one other issue last night which was around the dome closing, it suddenly did this around 10pm, not sure why, I think (I now in the light of day cannot be sure) the relay went off. Looking at the Keogram and then the ASC movie for last night it does coincide with a set of cloud going over so maybe that is why it closed. It will be nice to then get it to reopen when clear, another thing to fix at some point.

So as I say, setting up for the run was straightforward and I used TSX rather than SGPro to centre and platesolve M76 as normal. I then took a sample image of 60 seconds found that the focus was more or less spot on for OIII, despite earlier challenges with focus not working and all was ready to go.

On the point of focus problems, we could not get an accurate V-Curve earlier in the evening, SGPro kept coming up with different focus points after each run and eventually we put this down to the dome and scope not having had time to cool given it only being 30 minutes or so. The outside temperature was around 3℃ whilst the inside was just shy of 9℃. Later in the evening the difference was much smaller (I should remember to record this). I can get the ambient temp for the outside the next day from the FITS header but I have no record of the inside ambient temp, something else to fix.

So I went off to bed just after the meridian flip around 11:30pm and after watching a few frames come down. This morning I took flats and darks and closed the dome which was still open with the first frost of the season having set in and frost was covering the inside of the dome.

Viewing Report 12th July 2019 – IMT3 Observatory

Viewing time period – 20:32 – 22:56

After several reboots by GingerGeek who is looking after the observatory I am now logged in. I currently have the dome open and the 12″ centred on Deneb that can be clearly see whilst the Sun is still above the horizon and thus not dark yet.

The rebooting is due to hanging of the NUC. We have had various problems, the external ASI120MC with ASICAP/SharpCap and Firecap seem to cause an issue, we have a problem rebooting and the NUC just powering off and today trying to login through Windows and it was just hung. So lots of niggles.

Tonight I hope to test a single Ha guided exposure on the Elephant Trunk nebula in Cepheus to the North East as it rises and will look to image from 11pm for a few frames before closing the dome for the night. I have already noticed that Deneb is drifting in my FoV so something is still amiss with the polar alignment event though I thought I had it cracked. I will make a note to go back and check it. Currently Deneb is +42 Alt and 66 deg in Azimuth. I think the key will be looking at where I pick the star for polar alignment and making sure I have truly tightened.

So now it is nearly 10pm the sky is getting darker. The strangest thing happened, the dome closed. I only noticed as the image was blank. I checked and the Hitec Weather Station had tripped and closed the Dome. I toggled the Relay and then I could open the dome. Interestingly if you try to open the dome from TheSkyX it tries then stops and resets to closed. For the moment given the clear skies and forecast I have disconnected the Hitec Weather Station software but will reconnect later. Something else to debug.

HiTech Weather Station Software

It’s now 22:21 and dark enough to focus, I spent some time getting the auto focus routine working in SGPro. Interestingly I had to set the step size to 1000 given the 100k steps my FLI focuser is capable of. I also increased the data points to 10 and this gave me enough movement and data to get a good V curve.

I managed to get down to an HFR of on average 6 tonight at focus point 71290. It took me 3 runs to get the right figures. I then made the changes under the 12″ profile within Profile Manager and saved them for future use.

Auto Focus Run

Next I moved on to PHD2 and guiding. Once I got an image I then found I only had hot pixels and no stars. I also had a funny cone of light and something large out of focus and the edge of the tube. I then remembered GingerGeek had fitted a new guard ring to the guider camera and inadvertently moved the position due to a loose screw elsewhere on the fitting. Thus I need to go and focus that the next night out as because I am not there tonight I cannot do this. This also means I am stuck for testing a guided exposure.

Very out of focus Autoguider

So instead I tried a few different exposures with the Ha filter unguided even though I knew I had the problem with polar alignment. I took exposures at 120 seconds and 180 seconds by which time I had trailing, given as I said I had polar aligned and could image for 10 minute exposures in a different part of the sky I need to redo the aspect. Note I did not perform a second autofocus on the Ha filter. I will at some point calibrate the offsets of the filters once I have the auto guider working.

120s Ha Elephant Trunk area still not dark

So at least a useful night to try and get a few things working, a few things to add to the ToDo list but all in all a good evening.