Viewing Report 7th April 2020 – IMT3 – TPoint Failed

Viewing time period – 20:54 – 22:30

Old TPoint Model before new run

Tonight I set out to perform a TPoint run to improve the values we got last October. However it transpired to be more difficult than I thought. We updated TSX after October to there latest release, this seemed to have changed some of the parameters for plate solving. This meant that every time we took an image in the TSX it would not plate solve and so we could not perform the TPoint run. After the best part of 1 hour I gave up and let Bob take over the scope to play.

Meanwhile I then setup the Mac 180 to image Venus, however, by the time I got round to it and found it in the telescope and thus on the chip it was low down the side of the house opposite by the roof and was bumping around badly due to thermals. I found it difficult to centre the scope on Venus with such a small chip so I may need a more repeatable way of doing this moving forwards. I took a couple of videos just for posterity even though I felt the quality would be poor.

Subsequently the following day I opened up the images take with TSX and also download the All Sky Database that was missing to both the NUC in the dome and my local Mac. I then started to change the settings in Image Link within TSX until I could solve the image.

Solved image using Image Link All Sky Search in TSX

The key parameter transpired to be the Image Scale Tolerance on the All Sky tab setting it to 5% from 1%. Also I changed the Image Scale back to 0.32. On the Setup tab I selected Setup under Source Extraction and changed the detection to 10.0 and the minimum number of pixels to 20.0.

New Source Extraction Settings and solved image

I then tried a second image and that solved in 1 sec too so very happy. I will try to give the TPoint another go tonight as well as Venus on the Mac 180. If TPoint works I will take RGB on the Tak. First solution from the image I solved can be seen below.

TSX Image Link solved

The resulting astrometric solution from TSX is below based on another 60s exposure image is below as text.

******* ASTROMETRIC SOLUTION RESULTS ********

Center RA (2000.0): 07h 14m 12.34s

Center Dec (2000.0): +32° 34' 16.1"

Scale: 0.3250 arcseconds/pixel

Size (pixels): 4656 x 3520

Angular Size: 0° 25' 13" x 0° 19' 04"
Position Angle: 195° 28' from north through east

Mirror Image: No

RMS: 0.88 (X: 0.45 Y: 0.75)

Number of Stars Used in Solution: 40 (100%)

FWHM: 8.98 pixels, 2.92 arcseconds

***********************************************

Things still to resolve

  1. Check out why WSX is loosing connection and shutting the dome
  2. Clean filters for the 12″ to get rid of doughnuts
  3. Clean sensor for QHY168C

Viewing Report 4th April 2020 – IMT3 & Travel Setup Mak 180

Viewing time period – 18:42 – 04:21

Hoping to perform a TPoint run tonight, along with gathering some frames on M53 through all 3 scopes (along with Darks and Flats for the Esprit), as we only got some frames through the Tak yesterday. I also hope to try out the Mak 180 Sky-Watcher on the portable mount at the same time from the garden. I will also join the BAS Zoom meeting with all the rest of the gang on as we go through the night, which we have been doing for the past 11 days due to this unprecedented lockdown of society globally due to the Coronavirus, Covid-19 SARS-Coronavirus2 outbreak.

So progressed well tonight, spent the whole night on Zoom with the other astronomers so good company. Managed to image the following Lunar 100 objects, L13 – L30 – L42 – L53 – L59 – L65 – L68 as well as Venus which was at a phase of 44.75%.

@23:53 finished imaging with the Mak 180

Unfortunately M35 has now set and Bob is still imaging the Moon so I will have to grab M35 tomorrow early if it is clear……

I saw big problems with calibration with PHD2 which need to be looked at on the Tak.

@4:21am went to bed whilst the IMT3 was taking Darks

Things to still resolve

  1. Check out why WSX is loosing connection and shutting the dome
  2. Clean filters for the 12″ to get rid of doughnuts
  3. Clean sensor for QHY168C

Viewing Report 3rd April 2020 – IMT3

Viewing time period – 18:56 – 00:59

Opening dome to cool it down

So early on as always I opened the dome to cool down. Tonight Bob, Gingergeek and I want to image Venus in the Pleiades. Even before it got dark and as I slewed the telescopes to Venus, it was visible straight away so I took a quick image, 0.001s from both the 12″ and Bob’s FS102.

Venus 0.001s exposure from the OS 12″ during daytime
Venus 0.001s exposure from the Tak FS102 during daytime

I then went off to watch TV with Helen whilst Gingergeek and Bob grabbed some more images of Venus.

Around 10pm I re-joined Bob and GingerGeek and we set about imaging Venus as it passed by M45 Pleiades in the Tak FS 102. We then went on to perform autofocus on the Tak followed buy setting up the autofocus on the Esprit 120ED

Before the clouds decided to put a stop to play, we took some images of M53 the globular cluster on the Esprit around 00:10am using the Luminance filter.

Quick stack and stretch of M53 from Skywatcher Esprit 120 ED

By 00:59 the clouds finished play 🙁

Viewing Report 31st March 2020 – IMT3 12″ – Sync and Solve

Viewing time period – 20:30 – 22:20

Tonight GingerGeek, Bob and I wanted to make sure the newly installed version update for SGPro was working. In particular we wanted to get the sync and solve working, so that we could centre an object, but also the autofocus as the was a major update.

In TSX select an object and slew to it
In SGPro take a quick 5s image of the object
In SGPro click the Solve and Sync button on the bottom left
In SGPro the image is now solved and synced to in SGPro
In SGPro right mouse click on the object and select Center Here from the menu
In SGPro select Yes on the Center Telescope window
In SGPro take another 5s image using Frame and Focus
In SGPro the object should now be in the centre
In TSX from the Telescope tab click on the Start Up button and select Star Synchronisation
In TSX make sure Synchronize mount into existing model is selected and click on Sync
In TSX notice the FoV indicator from the camera has shifted to a new position
In SGPro take another 5s image using Frame and Focus
In SGPro the resulting image should not have moved

The mount in TSX and SGPro are now synced to the correct position in the sky.

Viewing Report 27th March 2020 – IMT3 12″

Viewing time period – 17:18 – 02:07

Cooling down telescope ready for tonights viewing

IMT3 Cooling down

M94 and NGC 3395/3396 are the 2 targets for tonight, some luminance on M94 and RGB on NGC 3395/3396 if I get enough time. I always try to open the dome early to give at least 2-4 hours cooling before I use.

View from the bridge

When I was about to start with autofocus I tried to recenter back on the target but the mount respond and it transpired that the mount thought it was out of balance. I went to the dome and the mount was beeping proving it was out of balance. So I turned the mount off, manually moved the scopes pack to the park position and then turned the mount back on and all was well.

@19:57 I performed the autofocus for the night on Luminance which scammer in at a position of 75282 on the focuser.

1st AutoFocus run

@20:10 I started an imaging run of 24 x NGC 3395/3396 with Luminance filter. Once done I planned on grabbing RGB frames before moving on to M94.

NGC 3395/3396 Luminance

@22:32 I started on the RGB frames for NGC 3395/3396 after refocusing on the Red filter.

Single Blue frame for NGC 3395/3396

@1:40 I slewed to M94 and changed the filter to Luminance. I performed a refocus and shifted from 77895 to 75884 on Red filter by accident. So we (I had Bob on Zoom by this point) refocused on the Luminance and the new focus position was 74884. So the difference is 1000 for Luminance to Red. I also changed the step size for the focuser temperature compensation from 531 to 431 to see if the HFR is more stable.

A new autofocus on Luminance

I noticed tonight that PHD2 lost the Use Direct Guide check mark twice and thus complained about pulse guide not being supported. I had to stop guiding, disconnect the mount in PHD2 and go into the settings, check the Use Direct Guide and reconnect the mount and start guiding again. Something to look into possibly.

Quick frame and focus 20s of M94 Luminance

@02:07 I went to bed and left the scope gathering another 2 hours of Luminance data on M94.

Addendum …….

The following day I took the ZWO ASI1600MM CMOS Camera off the back of the 12″ and cleaned the sensor window. What I found was the dark dust doughnuts disappeared and the rest for the doughnuts were actually on the filters.

Before cleaning Flat from Luminance on ASI1600MM
Flat from Red after cleaning sensor window
Flat from Green after cleaning sensor window
Flat from Blue after cleaning sensor window

Things to still resolve……..

  1. Check out why WSX is loosing connection and shutting the dome
  2. Fix Slew Here and Centre Here in SGPro that does not work
  3. Clean filters for the 12″ to get rid of doughnuts
  4. Clean sensor for QHY168C

Viewing Report 25th March 2020 – IMT3 12″

Viewing time period – 19:15 – 23:05

As I found last night I need to get Temperature Compensation working for the focuser if I am to produce any decent images. SGPro has a Temperature Compensation Trainer which I will follow.

Temperature Compensation Trainer in SGPro under Tools menu

I started @19:35 by taking an image of a star field to make sure there were no bright stars and then ran the autofocus routine. This came back with a focus position of 76974 at 11.5℃.

First autofocus run complete

Next I started the Temperature Compensation wizard which seems to measure the difference in focus position over a 5℃ decrease in temperature. It takes the initial reading above and then you wait until the temperature has dropped by 5℃.

Temperature Compensation Trainer Starting figures

It took 3.5 hours for the temperature to drop by 5℃. So @23:08 I then ran the autofocus routine and got the next image and result. This resulted in 531 steps per 1℃ of temperature change.

Autofocus after 5℃ drop in temperature

Viewing Report 24th March 2020 – IMT3 12″

Viewing time period – 18:16 – 01:43

Dome of IMT3 open and cooling down

Tonight I plan on setting the 12″ imaging M94, a Messier galaxy in Canes Venatici.

I slewed to nearby star and focused using SGPro after changing a couple of settings in the step size and amount of data points to be used, I set step size to 100 from previous 1000 and data point to 5 from previous 10 and got a much better focus. Focus landed up first time around at 738840

SGPro Autofocus settings changed

I had tried to get @focus working in TSX but it would fail every time on the galaxy with not enough stars. This meant I could not use TSX to solve and sync to centre M94.

SGPro autofocus

I then tried to centre with SGPro and that also failed so instead I used TSX to connect to the camera and manually moved M94 to the centre of the chip. I ned to get the local plate solver working as it was not running.

@ 20:32 I took an initial 5min sub to see what the image would be like after setting PHD2 guiding running.

5 min M94 sub

@1:20 and after gathering 3 hours of data I moved to other side of mount so meridian flip. I refocused as it had drifted a lot. I now need to consider setting up focus move for temp as the focus shift is dramatic. I also changed PHD2 Hysteresis setting to 0.20 from 0.10 as the PHD was having problems guiding.

I struggled to find guide star and landed up exposing for 15s and then having to increase, possibly needs recalibrating on this side of the mount. But also I need to find a brighter guide star by moving the mount offsetting the galaxy. The other way is using one of the piggy backed scopes which I may do next time.

@1:43 the dome closed, not sure why, might have been high cloud but probably because the WSX software lost contact with the WSX hardware. I did a reset and reconnected and then it was fine, but as the dome had closed I packed up with 3 hours of Luminance data on M94. I now need to take flats on the morning.

Single 5 min sub stretched in PI

Learning’s for next time……….

  1. Update the SGPro Equipment profile with the changes for step size and data points for autofocus
  2. Make sure the local plate solver is working and online at localhost
  3. Review Anydesk bug that changes mapping of keyboard
  4. Check out why WSX is loosing connection and shutting the dome
  5. Work out how to use temperature compensation for the focuser in SGPro
Flats from the following day at the same focus point

Viewing Report 23rd March 2020 – Travel Scope

Viewing time period – 18:23 – 04:08

@18:28 took flats for last night

PixInsight Flats from 120ED Esprit and QHY168C

@18:47 finished 20x -25℃ Flats 0.06s now taking Darks, will do more flats later when the cooler can get to -35℃ which right now it can’t as ambient outside temp is 7℃ so I can only get to -33℃ at 100%

ZWO Ezcap software for acquisition of Flats and Darks

@21:47 just finished Flats at -35℃

@22:49 started imaging Whale and Hockey Stick for Herschel 400

@00:47 I have 2 hours worth of data, performed meridian flip and continued to image the Whale for another 2 hours whilst I went to bed

@4:08 finished imaging and packed up

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 🙂 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 🙂

MUST REMEMBER TO TAKE FLATS TOMORROW!

IMT3 Tak QHY Camera Clean

Bob had noticed a lot of dirt on or near the sensor on the QHY168C camera that forms part of the imaging train on the Tak FS102. Today I took the camera off for a little spring clean.

The first thing was to mark the rotation angle of the camera so that it goes back on exactly. 21 degrees is the rotation angle as measured through an actual image.

Taping up position angle on QHY camera

Next I took the camera off loosing the 3 screws holding it in position and then took a look at the CMOS chop glass cover for dirt.

Inspecting QHY168C for dirt on glass cover

There was really only a couple of pieces of dirt on the cover so I removed them with the blower.

Rocket blower

Next I took off the extension tube with which has the glass UV lens inside. At this point I forgot to mark up the position angle when I took the extension tube off. So when I reattached I look at the image train photo to adjust. Hopefully it will be very close and will only require minor adjustment.

Tak FS102 QHY168C imaging train

Looking at the UV filter it was instantly visible that there was plenty of dirt and dirt on the glass lens, however it transpired to be on the inside of the lens toward the OTA. O removed the filter to clean with the rocket blower.

UV glass filter dirt and dust

I then reattached the filter, the camera and reset the angle. I followed up by feeling for any play in the Tak OTA bracket that piggy backs it on the OS12″ OTA. I could not feel any. I was checking due to a shift on the FoV when Bob was recently imaging. Again the next time out we will need to readjust.

Tak FS 102 piggy back bracket

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 2nd March 2020 – Travel Scope

Viewing time period – 19:30 – 23:00

Tonight I wanted to continue to try and get guiding working, I setup outside on a much calmer night, no real wind tonight. Bob once again is playing with the IMT3.

I setup in the same place on the patio and again fed the USB cable through the window. I used the Polemaster to get the mount in the right position and then slewed to Betelgeuse to see if it was in the centre and it was!

I then slewed to M35 and connected the guider with PHD2. After some back and forth I got it calibrated but it was complaining about the amount of steps being to small for calibration and the guiding was all over the place. The screen brightness was still very white. I solved this by changing the Gain for the camera.

I decided to give TheSky X a go at guiding instead of PHD2. Unfortunatly it was not much better and at one point I could see the downloaded image from the guider then suddenly it disappeared, I had changed nothing but now it was black. Nothing I could do would make it come back including disconnecting. So I went back to PHD2.

I managed to fix the issue in PHD on the amount of Steps being used to calibrate by adjusting the calibration step size down from 5333 to 1300. This increased the steps from 3 to 5. Much better and now I don’t get the error.

PHD2 good calibration

However right now I still cannot get the Dec to behave. Whilst I can take a 5 min image the Dec is wonder up from where it should be and no amount of tweaking the Aggressiveness or Hysteresis changes that.

Furthermore, I decided to take images with The Sky X over EzCap but after 4 images TSX hangs every time……. So I have now given up tonight and will come back out the next cleanser night to resolve the issues.

PHD2 DEC drift up!

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

Analysis Report for first partial Exoplanet Data – IMT3 Observatory

I managed to get only 45 minutes worth of data the other night to test if I could both acquire data and then process it. It took some time to get the downloaded HOPS software from the ExoClock mission working on my Mac, but with the help of Angelos from the project. So I opened the 46 images, I did not capture darks or flats and of course no bias due to it being a CMOS camera. I added information about the observatory and then ran the reduction and alignment code.

Completion of details and opening of 46 images

So the initial chart looked promising, I had taken the first set of frames almost on time for the transit even though you are supposed to start 1 hour before. This was because it took me so long to setup. So the data looks like it shows a decrease in brightness over the 45mins, however I have asked Angelos for his opinion and await a response.

Output from clicking Run Reduction

I then selected the target star, KELT-18 with the red circle below, along with 5 comparison stars. I may have selected stars incorrectly here as they are probably suppose to be not variable.

Alignment and comparison star window

The resulting table appeared with the size of the box for each star and its position.

Resulting target and comparison stars

I then ran the photometry code and the following chart was created which to me showed I had done something wrong given the scatter.

Graph output with actual photometric values and PSF in red

I then for fun ran the fitting code from this screen.

Information for Fitting

The fitting showed and increase in brightness which was clearly incorrect. So I have learned a few things with this, first is to read up on using the software for analysis, second is to gain more data and calibration frames.

Resulting output clearly showing problems with data

Viewing Report 29th December 2019 – IMT3 Observatory

Viewing time period – 17:43 – 17:48

EXOPLANET – HAT-P-20b

Slightly hazy right now but I have opened the dome up and turned the cooling fans on the 12″. Slewed to Atik, a mag 2.8 star in Perseus and aligned the scope.

Atik mag 2.8 star in Perseus for alignment

So the star was almost in the centre when I slewed the scope to it, a slight tweak and now synced on it centrally. The Hitec Astro weather station reports slight haze

Hitec Astro Weather Station showing haze

Gingergeek installed a new Intel Windows small form factor computer recently in replacement for the RPi so we could run the AllSkEye software and see if the loss of one of the colour channels was software or hardware. Here is tonights image, which still needs colour calibrating during the day.

AllSkEye camera software

Viewing Report 25th December 2019 – IMT3 Observatory

Viewing time period – 19:10 – 20:32

EXOPLANET – KELT-18b

As always on Christmas Day, or at least it seems so, the sky was clear for a period of time before the clouds rolled in. The day was dry and cold, sunny and bright, the first time in over a month of rain. Now was the time to take a look at a star and see if I could calibrate my setup for imaging an exoplanet transit.

All Sky Camera

I used the exoclock.space website to find objects for my location and then entered the RA and DEC into The Sky X (TSX) and slewed to it. The star and its associated planet tonight was KELT-18 and the planet KELT-18b. This was very low to the North when I slewed and I struggled doing a slew and sync with the scope in TSX due to not enough stars found.

Exoplanet Target List from Exoclock.com

So instead I placed the RA and DEC into SGPro and asked that to perform a slew and solve, which incidentally worked an absolute treat. The star was centred in the middle of the FoV and the star pattern matched that from the Exoclock website which they give you.

Kelt-18b details including interactive star map

I then setup SGPro to take as many images as I could, each being 1min long as I could not find a guide star. At 1min I did not get any trailing and I should have said, all of this through the 12″. I set the cooler to -28℃ which consumed about 26% power so nicely cold. I choose the red filter as described to lower the amount of noise in the image and allow calibration with other astronomers images.

Resulting image

I had to change the user profile to the Comet profile as I did not wan the guider trying to settle, so restarted the run and was off. I managed to go for around an hour and thus grabbed 46 images. I am not sure if I can use the HOPS software from Exoclock to plot these but will try. I did not bother with calibration frames and if needed I can grab some later.

SGPro sequence running

Either way, a good hours viewing in-between the outgoing festive cheer from one side of my family and the incoming festive cheer tomorrow from the other.

Merry Christmas and Clear Skies

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 🙂

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 22nd/23rd October 2019 – IMT3 Observatory

Viewing time period – 21:38 – 01:50

Quick set of images this evening to take some more data of M76. I can image for 3 hours before a meridian flip. I need to get the automated flip working and thus the plate solving that seems to be having issues. For now I will open the dome and just set it running on OIII through the 12″.

After entering with TSX connected to the ASI camera I started guiding and for setup reasons I have included the guide star here.

Guide Star

@00:45 I managed to do the manual meridian flip and then headed off to be after collecting another 2 hours of OIII data. I left the scope running for the rest of the night knowing that the dome would shut if the sky clouded up.

Last image taken

So I am now up at 7am and indeed the dome closed when the clouds rolled in. I have no real notification of when that occurred so I have now set the HitecWeather station software to log on the triggering of the relay to a file so I can see the time it closed.

This will allow me to compare to the Keogram from the ASC and double check the dome is closing at the appropriate time.

Fortunately SGPro is connected to the weather station as a safety monitor and stops imaging if the dome closes. I can see the clouds started to roll in around 1:30am for a few minutes then just before 2pm there were more and by 2:43am after they covered the sky. The good thing is it looks like, although I cannot be sure, the dome would have closed at around 1:50am which is the time of the last image taken assuming the date stamp is the completion of the image.

Safety enabled

I have now taken flats and darks and parked the scope and it is ready for it’s next outing, I also remembered to turn the dehumidifier back on this time. Both the dehumidifier and the flat panel need connecting to an Arduino to automate turning on and off.

View from cameras when in position to flat panel on 12″

Viewing Report 19th/20th October 2019 – IMT3 Observatory

Viewing time period – 17:31 – 01:48

After nearly a month of not imaging from IMT due to a holiday in Tenerife, a week in New York with work and then Manchester and London along with a run of poor weather it was clear on a Saturday night! Another evening commissioning the observatory was needed, so tonight we will again further refine the polar alignment since the last major modification and distribution of weight where we changed the adjustment plate for Bob’s Tank FS 102 OTA. Again we plan to drift align with PHD.

First thing is to find a star near the celestial equator near the Meridian so that it would display the most movement and thus magnify the error of miss polar alignment. I should be able to find HP 95501 @8pm.

Star to drift align for Azimuth

Next I performed an autofocus using the Luminance filter. HIP 95501 is the star to choose for drift aligning the first part, a 1 second image within Frame and Focus in SGPro showed it just off centre which was fine.

Star to guide on

Next I moved the star to place in the Lodestar FoV. Now I can measure the azimuth polar error, ALWAYS ignoring the RA line. Looking at the Dec line I could see I was out by 2.43′ and 39px. I adjusted the thruster knobs on the MEII to move the star to the outset edge of the purple circle showing the error, in this case the right thrust in and left thrust out. I then drifted again and make sure the purple circle gets smaller and the DEC line a much shallower angle.

After first adjustment 0.53′ and 34px out

I adjusted again and got the azimuth error down to a respectable 0.08′ 5px error.

Azimuth error 0.08′ 5px

The graph on PHD2 should started to look fairly flat, and so I then attempted to fix the polar error for altitude. I selected a star in the West and near the celestial equator such as Rasalgethi in Hercules.

Rasalgethi used for Altitude adjustment

I watched the DEC line only and ignored the RA, the DEC line this time reflecting the error in altitude. Then I adjusted the mount using the altitude adjustment spanner moving the star again to the outside of the purple circle and then retested, finally getting the error down to a suitably small number after only 1 turn of 0.12′ 5px error.

Altitude adjusted to 0.12′ 5px error

Unfortunately at the extreme West I could only expose unguided for 1min on the 12″ at 2.5m focal length, the stars otherwise looked trailed.

Trailed stars at extreme due West

I then went to near the meridian and a 4 min exposure produced nice sound stars.

4 minute exposure near Meridian

I then went on to do an automated TPoint run, but the problem seemed to be that a large number of samples could not be solved. The resulting TPoint model of 118 samples of which only 90 were usable, was worse than the 60 point model I had before. I will therefore redo the TPoint model the next time it is clear.

TPoint model not as great at 60 points I did before

The whole 118 model took approximately 1.5 hours to complete which is so much better than a manual model.

Completed model 118 points

The good thing is the TPoint model told me the polar alignment is excellent!

Polar Alignment is excellent 🙂

It is now @23:30 so I went on to start imaging. First I needed to perform a focus run on Luminance which I did.

Good focus on luminance

I then slewed to M76 to start my image run, a 30s exposure showed stars in focus and little dumbbell prominent in OIII.

Focused stars and M76 centred

This time round I decided to set the Gain to 139 and the Offset accordingly to 21. I also decided on a 10min exposure rather than 20mins front the last set.

M76 1 x 10min Gain 139 Offset 21