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Skywatcher AZ GTI mount owners thread


AstroNebulee

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32 minutes ago, bomberbaz said:

Apart from the big star bottom right which looks like it's in the middle of an Einstein's cross 😃.

Need to remember how to create a star mask now, lol. 

Yep I didn't look that closely in my phone, kinda cool though. God star masks 😬, still not learnt properly but fudged my own sort of process 😂

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Got the az gti out again tonight probably last dso until late July. Finishing off my tests and think I'll stick at 63.8mm back focus for now. Probably could do with a couple more 0.mm but but being really picky I think and I'm scrutinising to much. 

Guiding not as good as last night,bit of high cloud here and there but averaging 1.7-2.5 rms though. Got to check if I meshed the worm on the RA gear and fixed the spring instead of activating the spring loaded mechanism. So that's moros job. 

Got a few more subs on ngc 7000 so will check them moro too. I'm in now feeling really tired and bit chilly, I really envy the astrophotographers who can image ring inside and leave their scopes chugging away. 

Hope others are getting some action in tonight, wherever you are and whether your imaging or observing. 😊

Good night all. 

 

Edited by AstroNebulee
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Mine is going away in two weeks after my birthday.  I would like to try, if I can make rig with the calibration steps set as discussed on other thread and also find out what any others should be ( if there is an equation that is)

Useful info here for anyone with the asi air on setting up your calibration settings but i believe this carries through to any mount.

 

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12 hours ago, AstroNebulee said:

Got the az gti out again tonight probably last dso until late July. Finishing off my tests and think I'll stick at 63.8mm back focus for now. Probably could do with a couple more 0.mm but but being really picky I think and I'm scrutinising to much. 

Guiding not as good as last night,bit of high cloud here and there but averaging 1.7-2.5 rms though. Got to check if I meshed the worm on the RA gear and fixed the spring instead of activating the spring loaded mechanism. So that's moros job. 

Got a few more subs on ngc 7000 so will check them moro too. I'm in now feeling really tired and bit chilly, I really envy the astrophotographers who can image ring inside and leave their scopes chugging away. 

Hope others are getting some action in tonight, wherever you are and whether your imaging or observing. 😊

Good night all. 

 

Quoting my thread from last night.  I have opened up my az gti mount and saw that the RA spring was disengaged and the worm meshed to the gear (I must of reversed it back sometime?) so today I have gone back to using the spring on the RA worm and gear to see if any improvements or major differences then further testing on the next clear night. One day I will stop tinkering with my mount haha.

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More tinkering. I checked all my images from last night and it seems every sub had a little drift, not sure why that is.

Anyway, and sorry for the deluge of images I am putting up three pics. 

  1. The first effort from last night with 9 subs.
  2. A rework using PyAstro.
  3. A further rework of just 2 subs but with a Dual banded filter.

Notice the slight star trail on my first effort, this was before I installed and used PyAstro in gimp.

M57.thumb.jpg.3597d540b7a32a2442b24518b77f82ed.jpg

The rework below got overdone and I finished up with an Einstein cross on the bright star bottom right.

2033807421_M57new.thumb.jpg.2eadf0ff5144788d173a7cee0bd060c0.jpg

Considering this one below is from just 6 minutes of data (2 subs) I am more than just a bit pleased, possibly a tad over stretched. I used the ZWO dual band filter for this one. Now if I can just get the AZ mount tracking right, I think I will be on my way to cracking it.

Looking at this image though, I am amazed at the number of interesting little asterisms around it which I have never noticed visually. Next time out at a dark place I shall take this along with me (inverted as a map) to try and find some of them, although they may be beyond the T350!

1545560471_m57uhconly.thumb.jpg.f6d98f2d4dc81a917da12664892e6ad4.jpg

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Regarding drift do you recalibrate after each slew before imaging? Also I assume your tracking is on and set accordingly.

My last session for some reason the asiair decided to turn off tracking after each calibration which is not what it used to do. My sidereal rate is set at 0.9x. I was imaging at 200mm though, so even dithering a few pixels didn't matter to the subs (was using a dual setup).

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8 hours ago, bomberbaz said:

More tinkering. I checked all my images from last night and it seems every sub had a little drift, not sure why that is.

Anyway, and sorry for the deluge of images I am putting up three pics. 

  1. The first effort from last night with 9 subs.
  2. A rework using PyAstro.
  3. A further rework of just 2 subs but with a Dual banded filter.

Notice the slight star trail on my first effort, this was before I installed and used PyAstro in gimp.

M57.thumb.jpg.3597d540b7a32a2442b24518b77f82ed.jpg

The rework below got overdone and I finished up with an Einstein cross on the bright star bottom right.

2033807421_M57new.thumb.jpg.2eadf0ff5144788d173a7cee0bd060c0.jpg

Considering this one below is from just 6 minutes of data (2 subs) I am more than just a bit pleased, possibly a tad over stretched. I used the ZWO dual band filter for this one. Now if I can just get the AZ mount tracking right, I think I will be on my way to cracking it.

Looking at this image though, I am amazed at the number of interesting little asterisms around it which I have never noticed visually. Next time out at a dark place I shall take this along with me (inverted as a map) to try and find some of them, although they may be beyond the T350!

1545560471_m57uhconly.thumb.jpg.f6d98f2d4dc81a917da12664892e6ad4.jpg

What is your tracking rate set to Steve? Mine is set to 0.9x too same as Elp. Could be worth changing your tracking rate. Also how close is your PA? I've seen drift like this before but not sure if it's doing it in RA or Dec, someone will know which. 

Cheers 

Lee 

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11 hours ago, bomberbaz said:

More tinkering. I checked all my images from last night and it seems every sub had a little drift, not sure why that is.

Anyway, and sorry for the deluge of images I am putting up three pics. 

  1. The first effort from last night with 9 subs.
  2. A rework using PyAstro.
  3. A further rework of just 2 subs but with a Dual banded filter.

Notice the slight star trail on my first effort, this was before I installed and used PyAstro in gimp.

M57.thumb.jpg.3597d540b7a32a2442b24518b77f82ed.jpg

The rework below got overdone and I finished up with an Einstein cross on the bright star bottom right.

2033807421_M57new.thumb.jpg.2eadf0ff5144788d173a7cee0bd060c0.jpg

Considering this one below is from just 6 minutes of data (2 subs) I am more than just a bit pleased, possibly a tad over stretched. I used the ZWO dual band filter for this one. Now if I can just get the AZ mount tracking right, I think I will be on my way to cracking it.

Looking at this image though, I am amazed at the number of interesting little asterisms around it which I have never noticed visually. Next time out at a dark place I shall take this along with me (inverted as a map) to try and find some of them, although they may be beyond the T350!

1545560471_m57uhconly.thumb.jpg.f6d98f2d4dc81a917da12664892e6ad4.jpg

Sorry I can't offer any imaging advice! But on the subject of the starfields in/around Lyra, I recently was in darker skies (Bortle 5 instead of 7/8) with a basic 70mm scope showing max TFOV of about 4° and was also surprised at the richness of that area. Loads of stars I had never really seen properly before, I ended up spending ages panning around there when I took in the various multiples as well. 

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51 minutes ago, badhex said:

Sorry I can't offer any imaging advice! But on the subject of the starfields in/around Lyra, I recently was in darker skies (Bortle 5 instead of 7/8) with a basic 70mm scope showing max TFOV of about 4° and was also surprised at the richness of that area. Loads of stars I had never really seen properly before, I ended up spending ages panning around there when I took in the various multiples as well. 

Yeah it is a very rich field Joe, I am particularly keen to get onto this (annotated) asterism which I have named the christmas tree for obvious reasons.

I think I am going to need highish power but after a play on stellarium to check magnitudes, I think much of it is possible. 

676993718_m57xmastree.thumb.jpg.5c3bc27b309c7e3bdd5890064fd9d6bb.jpg

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Very useful article here on the guide settings including a guide testing method.  I have cut and pasted the main part but also attaching the link, well worth a read guys. 

The next thing we can control is the guiding rate or guide pulse multiplier.  In ASIAir this is found under mount settings as .25x, .5x(default), .75x, and .9x.  The baseline guide pulse is the pulse sent to mount to keep things moving at the sidereal rate.  When a corrective guide pulse is issued, this setting will send a pulse as .25x the sidereal pulse, .5x , etc. Every mount is different and responds differently.  Most will find that .5x is perfect but not always so.  My Orion mount corrects best at .75x.  For some mounts these settings are not offered in the app and must be set on your hand controller.  You can determine which setting is best by setting both RA and Dec aggression to 50%.  Then try each multiplier setting and watch the total rms number.  Wait for the graph to measure the full width of the chart using the selected setting.  You can use 1s guide exposure for this part to speed up the process.  Choose the setting with the lowest rms error.  Note that as of version 1.5.3 this setting is not persistent and will reset to .5x at boot up.  Another thing to file in the back of your mind is to consider the guide pulse multiplier as a course setting and the aggression sliders as a fine tune setting.  As you try larger or smaller guide pulse multipliers you may need to decrease or increase the aggression to get the best guide.  If you find your aggression is too high or low you may need to adjust the multiplier to keep your aggression in the middle of the range.

East Wind Astrophotography: February 2021

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I've been reading some guiding / drift issues above so thought I'd share my set up ASI Air Pro settings as I rarely (if ever) get such issues with either DSLR or ASI 533mc pro.  For reference I use the Astro Essentials 30mm mini guide scope + ZWO ASI 120mm mini camera on top of my WO Z61ii scope.  The AZ GTi is stock (I haven't opened it to fiddle with the insides at all) and I use the Skywatcher eq wedge.

Camera and memory stick inserted to ASI Air usb 3 ports.  Guide camera and mount (via eqmod cable) into usb 2 ports.

Make sure the mount is level and balanced then turn on the AAP first once everything is connected and in position.  Wait for the beep then turn on the mount.  Open up the AAP app on my iPad once it's all switched on.

Roughly focus then polar align (I can spend ages doing this).  I'm not happy until I'm within 00° 00' 10".  I can't stress enough how important for me this step is.

Slew to a nearby star (I use the AAP's goto function) to finalise focus using a Bahtinov mask.

Slew to my target (again using the AAP's goto function).  Once in a blue moon the mount might go a bit crazy and slew in a seemingly random fashion, at which point I'll turn it all off and start over.  I seem to have got over this issue now that I've changed how I power the mount (from the AAP rather than an old dusty power adapter I found in a drawer).

Guiding - in the guiding screen to start guiding all I touch are the circular arrows button over on the right to start refreshing, then I'll focus the guide camera (gain set to around 80 so I can see properly to focus) followed by the circular target button to start guiding.  "Exp" (bottom right) is set to 1 second.

At the bottom of that screen next to the graph, RA Aggr is set to 100%; DEC Aggr set to 100% and DEC Mode is set to Off.

I then minimise that screen so that the small guide graph is visible, take a test shot of my night's target and, once happy, set up my imaging run.

In terms of other Guide Settings (button at the top) from the top down:

Guide Camera - ZWO ASI 120mm mini (picked up automatically by the AAP)

Guide scope focal length - 120mm (make sure that's accurate)

Gain - 77 (changed when I focus the guide camera)

Calibration step - 1000ms

Max DEC duration - 1000ms

Max RA duration - 1000ms

Auto restore calibration - set to on

Guide camera bin 2 - off

Guide stability settings - Stability 1"; Settle time 3s; Timeout 60s.

Dither settings - it's switched off.  I don't bother with dithering with the AZ Gti.  I've had very mixed results with it and don't bother any more.

 

Mount Settings

Mount - EQMod mount selected and switched on

Serial connected; Baud 9600

Goto Auto Center - turned on

Center Exp Time - 2s

Guiding Rate - 0.5X

Tracking - turned off

 

I think that covers it.  I'm normally guiding around 1 - 1.2 Total (quite often below 1, sometimes higher) which is fine for my 360mm fl / 61mm dia scope.  2 or 3 min subs are my norm, 5 mins I'll set rarely and I've had it as high as 10 mins without issue.  On occasion I'll notice a very minor amount of drift between subs but we're talking fractions here from first sub to last in a multi-hour imaging run.  It's so minor it's not an issue and causes no problems when stacking.  Hope that helps if you've been having problems 👍.

Edited by herne
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3 hours ago, herne said:

Guiding - in the guiding screen to start guiding all I touch are the circular arrows button over on the right to start refreshing, then I'll focus the guide camera (gain set to around 80 so I can see properly to focus) followed by the circular target button to start guiding.  "Exp" (bottom right) is set to 1 second.

Thank you, that's a brilliant explanation and readout of your process and workflow setting up 👍. You have some excellent guiding there. Quite similar to my set up process. Do you clear your calibration before you set your guiding going, I have auto restore calibration switched off, so it shouldn't keep the previous calibration set, though I do clear it just incase, then press the looping icon then the target icon, let it pick my guide star (as long as its around 3-3.6 hfd) and multistar guide too. let it calibrate then off it goes guiding when calibrated. 

3 hours ago, herne said:

At the bottom of that screen next to the graph, RA Aggr is set to 100%; DEC Aggr set to 100% and DEC Mode is set to Off.

I have mine dec mode set to auto though I do dither, which is a revelation to me and have the settle time to 3s and under 4" as it would take to long to settle anything under that after a dither. 

Some other settings are different but in the end it what works for each person and no 2 mounts ever seem the same to me, with different scopes and such. but gives everyone a nice guideline to work from, thank you 😊

Cheers 

Lee 

Edited by AstroNebulee
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3 hours ago, bomberbaz said:

Very useful article here on the guide settings including a guide testing method.  I have cut and pasted the main part but also attaching the link, well worth a read guys. 

The next thing we can control is the guiding rate or guide pulse multiplier.  In ASIAir this is found under mount settings as .25x, .5x(default), .75x, and .9x.  The baseline guide pulse is the pulse sent to mount to keep things moving at the sidereal rate.  When a corrective guide pulse is issued, this setting will send a pulse as .25x the sidereal pulse, .5x , etc. Every mount is different and responds differently.  Most will find that .5x is perfect but not always so.  My Orion mount corrects best at .75x.  For some mounts these settings are not offered in the app and must be set on your hand controller.  You can determine which setting is best by setting both RA and Dec aggression to 50%.  Then try each multiplier setting and watch the total rms number.  Wait for the graph to measure the full width of the chart using the selected setting.  You can use 1s guide exposure for this part to speed up the process.  Choose the setting with the lowest rms error.  Note that as of version 1.5.3 this setting is not persistent and will reset to .5x at boot up.  Another thing to file in the back of your mind is to consider the guide pulse multiplier as a course setting and the aggression sliders as a fine tune setting.  As you try larger or smaller guide pulse multipliers you may need to decrease or increase the aggression to get the best guide.  If you find your aggression is too high or low you may need to adjust the multiplier to keep your aggression in the middle of the range.

East Wind Astrophotography: February 2021

Thank you Steve. Its a great article and gives a good insight into guiding with the asiair. 👍

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Think next time out I will not bother dithering. With my scope FL and fov the walking noise will be minimum and pyastro tools can remoove whats left. 

I am actually wondering if the dithering is too blame for the drifting.

Thanks @hernefor your settings walk through.

I will build a settings sheet walk through with tips and pointers for next time out using some of your info plus stuff from my link above. I think taking a methodical approach will help in ironing things out. 

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1 hour ago, AstroNebulee said:

Do you clear your calibration before you set your guiding going, I have auto restore calibration switched off, so it shouldn't keep the previous calibration set, though I do clear it just incase, then press the looping icon then the target icon, let it pick my guide star (as long as its around 3-3.6 hfd) and multistar guide too. let it calibrate then off it goes guiding when calibrated. 

I'll double check what it's set to the next time I'm out (if I remember!) but I know I don't do anything with clearing the calibration.  I also let it pick my guide star but not multistar guiding.

1 hour ago, AstroNebulee said:

I have mine dec mode set to auto though I do dither, which is a revelation to me and have the settle time to 3s and under 4" as it would take to long to settle anything under that after a dither.

Good job getting dithering to work on the AZ GTi 👍.  It's not something I got on very well with.  Perhaps I'll try again at some point although I'm quite happy with my results without.

1 hour ago, AstroNebulee said:

no 2 mounts ever seem the same to me

Yeh exactly.  There will always be small variances in gears and whatnot so the more information sharing the better to give others ideas and things to try 🙂.

10 minutes ago, bomberbaz said:

Thanks @hernefor your settings walk through.

I will build a settings sheet walk through with tips and pointers for next time out using some of your info plus stuff from my link above. I think taking a methodical approach will help in ironing things out. 

I think a methodical approach can sometimes help.  Even something as basic as the order in which we switch on equipment might have an impact.

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14 minutes ago, herne said:

I'll double check what it's set to the next time I'm out (if I remember!) but I know I don't do anything with clearing the calibration.  I also let it pick my guide star but not multistar guiding

I expect its set to not restore the calibration form last time like mine. 

You've definitely got a perfect set up 👍

I know when a guidestar is chosen by the AAP or chosen by the user that the peak of the graph on the star hfd needs to be a nice peak and not flat or missing at the top. 

 

IMG_20220530_143452.jpg

Edited by AstroNebulee
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A little bit of tinkering and whatnotting on my set up after work today. 

I set about giving it a damm good balancing session. I didn't use the Italian Belgium chaps tutorial as I didn't like the thought of all my kit on there and trying to hold and balance it, then knowing my ability to be a clumsy butterfingers I'd only cause issues 😬.So I did it on the tripod itself.

The Dec balancing was ok. The the RA was a little scope heavy, I couldn't move my weights any further down the bar so I've added a homemade counterweight out of an old disc of steel and added to the bottom clamped by the original counterweights. 

I also checked the bolts and screws on the tripod and extension pier, just a note to others with this star adventurer tripod that's sold with the az gti check the Allen bolts at the top of the tripod legs for play as mine have needed to be tightened a couple times now. I will eventually get the skywatcher 3/8th steel tripod for more rigidity and sturdyness. 

Cheers 

Lee 

IMG_20220530_181543.jpg

IMG_20220530_184329.jpg

Edited by AstroNebulee
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42 minutes ago, bomberbaz said:

I lengthened my balance bar the other day Lee, useda 2 inch bolt, took around 2 cm to lock up then skid the weights down the extra 1 inch or so. Balanced it bob on. 

Sounds great Steve. My counterweight bar is a 30cm m12 bolt with about 2 inches of thread to go into the az gti mount. The bike head is fixed so I can't add anymore length to mine. I have just found a 40cm m12 part threaded bar on ebay so ordered it and should gain the extra length now. I'm hoping my latest tweak here will work until the bar comes.

This is the link to the bars, lots of lengths on offer if anyone is looking for one for their az gti.

https://www.ebay.co.uk/itm/383682199393?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=g4gbkfnlsh6&sssrc=2349624&ssuid=Fo3Iht4XRKy&var=652081108589&widget_ver=artemis&media=COPY

👍

Edited by AstroNebulee
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1 hour ago, AstroNebulee said:

Sounds great Steve. My counterweight bar is a 30cm m12 bolt with about 2 inches of thread to go into the az gti mount. The bike head is fixed so I can't add anymore length to mine. I have just found a 40cm m12 part threaded bar on ebay so ordered it and should gain the extra length now. I'm hoping my latest tweak here will work until the bar comes.

This is the link to the bars, lots of lengths on offer if anyone is looking for one for their az gti.

https://www.ebay.co.uk/itm/383682199393?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=g4gbkfnlsh6&sssrc=2349624&ssuid=Fo3Iht4XRKy&var=652081108589&widget_ver=artemis&media=COPY

👍

I use a 40cm threaded bar myself.  Bought it as a 1m length from B&Q (I think) and cut it down.  I still have a 60cm length left over I can use if I want extra length although much longer and it might become a bit ungainly.  Actual weights instead of my nuts and washers would perhaps be better.

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15 minutes ago, Priesters said:

Nice location but a few ‘characters’ around this car park at the moment so maybe my last post 😂.  Hoping for a clear night and a shot at NGC 6974 🤞8974E69D-0AD8-41ED-BCDE-E3405063FCEC.thumb.jpeg.b8d6e70f75d773aca0ac289b943d6c73.jpeg

Haha good luck, make sure you give us your what 3 words address, keep everything well buttoned up and unaccessible 😬

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20 minutes ago, Priesters said:

Nice location but a few ‘characters’ around this car park at the moment so maybe my last post 😂.  Hoping for a clear night and a shot at NGC 6974 🤞8974E69D-0AD8-41ED-BCDE-E3405063FCEC.thumb.jpeg.b8d6e70f75d773aca0ac289b943d6c73.jpeg

Nice view of pendle there, are you up wycoller way?

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