March 2020 – IMT3b Observatory

Viewing Report 27th March 2020 – IMT3 12″

Viewing time period – 17:18 – 02:07

Cooling down telescope ready for tonights viewing

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.

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.

@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.

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

@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.

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……..

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

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.

Viewing Report 24th March 2020 – IMT3 12″

Viewing time period – 18:16 – 01:43

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

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.

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.

@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.

Learning’s for next time……….

Update the SGPro Equipment profile with the changes for step size and data points for autofocus
Make sure the local plate solver is working and online at localhost
Review Anydesk bug that changes mapping of keyboard
Check out why WSX is loosing connection and shutting the dome
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.

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

@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

@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

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

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.

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.

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.

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.

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.

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.

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!

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.

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.

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.

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.