Skywatcher AZ GTI mount owners thread

[AstroNebulee]

3 minutes ago, bomberbaz said:

I have aactually just done some subs of the monkey head neb at 60,120 & 180 although I have used a little more gain at average 165 so maybe overcooking it. 

I shall see upon my results. 

165 gain could be good it's all about experimenting, I wish I could image the monkey head but after meridian no good, look forward to seeing your results 👍

[AstroNebulee]

53 minutes ago, RayWUK said:

How long do you have to allow between subs when dithering? I only tried it once and the guiding failed after each dither and took ages to lock on again. I was wasting almost half my imaging time waiting for the guiding to settle again.

I dither between each frame and it has to be under 4 for 2 secs to start the imaging again. I also set it to dither 5 pixels. 

I have found that since doing the mesh mod on my dec motor its so much quicker as I used to waste so much time dithering and settling. Now it's around 12 mins for every hour of imaging which for this mount is pretty good I think. 

You can dither every 2 or 3 frames I've read but every frame works for me, it's worth experimenting on how many frames then dither any fitheting will be an improvement. My images are so much better for it. 

I'm no expert by any means on imaging just saying what works for me and what I've learnt 😊

Also what set up were you using at the time Ray? 

Edited March 23, 2022 by AstroNebulee

[bomberbaz]

24 minutes ago, AstroNebulee said:

165 gain could be good it's all about experimenting, I wish I could image the monkey head but after meridian no good, look forward to seeing your results 👍

Just a quick FYI is the data I captured has dust motes on it and as I forgot to get flats it might be for deleting. Not sure if it is rescuable as i am still a little unsure about the capturing of flats. Fine with darks and bias 

[RayWUK]

First attempt at the Rosette Nebula.  Only managed 70subs of 120secs over two nights as its getting low in the sky now by the time it becomes visible from my backyard.

[AstroNebulee]

17 minutes ago, bomberbaz said:

Just a quick FYI is the data I captured has dust motes on it and as I forgot to get flats it might be for deleting. Not sure if it is rescuable as i am still a little unsure about the capturing of flats. Fine with darks and bias 

Has the set up moved a lot since took your data tonight or focus moved? You maybe be able to get away with taking them the next day after. As they should generally be taken after an imaging session. Some people take the morning sky for their flats if the setup hasn't moved. Best is to do it straight after imaging that night and retake them after every session. 

I use a flat panel light box I made. Using the flats tab in AAP autorun, I set it to 2 sec subs and try to get the hump of the histogram just under half way on the histogram. If it's to high up the histogram I add another sheet of paper or to low I take a sheet of paper away. I have perfected it so now I just pop the flats panel over the scope and fire off 30 flats whilst packing up at the end of a session and the hump in histogram is just under halfway (sorry don't have an image of this) You could just stretch a t shirt over the end of the scope, use a tablet screen or phone screen set to white as long as it covers the whole aperture of the scope and use the auto flats option in the AAP autorun will work. 

Edited March 23, 2022 by AstroNebulee

[AstroNebulee]

23 minutes ago, RayWUK said:

First attempt at the Rosette Nebula.  Only managed 70subs of 120secs over two nights as its getting low in the sky now by the time it becomes visible from my backyard.

Gorgeous Ray and lovely colour in the rosette and stars 👍, if you can reduce the stars in processing it'll make the rosette pop even more. 😊

Edited March 23, 2022 by AstroNebulee

[RayWUK]

4 minutes ago, AstroNebulee said:

Gorgeous Ray and lovely colour in the rosette and stars 👍, if you can reduce the starsin processing it'll make the rosette pop even more. 😊

I'm working on it, still getting to grips with StarTools.

[AstroNebulee]

6 minutes ago, RayWUK said:

I'm working on it, still getting to grips with StarTools.

Same here Ray👍, I use star tools and when in the shrink module, classic mode works quite well for that for a quick fix but  I've still a lot to learn in star tools too, I'm no expert honestly 🤣 I'm still learning so much in star tools that I even printed off the manual at 284 pages long 🤣 and you'll all notice I can't spell too (fingers to fast for ickle keyboard and I don't look at what I've typed.)

Edited March 23, 2022 by AstroNebulee

[AstroNebulee]

Just got in from grabbing 2 hours worth of data on M101 tonight, so pleased to be back out under a moonless, windless, clear night sky even if the transparency was rubbish. Couldnt really make Virgo out atall and Leo was washy. 

And quick couple of screenshots, guiding was very good too using multistar guiding. 

Hoping to grab more data on it moro night if it stays clear. 

 

Edited March 24, 2022 by AstroNebulee

[badhex]

Was out with the AZ-GTi and ZS73 last night for the first time since last November! 

I had momentarily forgotten several things, like how much additional stuff you have to do for setup vs completely manual alt-az. That said, the manual alt-az I've been using recently was a Skytee-2 and EQ-6 tripod which I did not miss carrying up two flights of stairs. 

I luckily plonked down the tripod in spot where it was completely level, and after setting everything else up including first proper use of the Celestron battery I bought last year, I started north-level alignment which took two attempts: the first slew being completely off as the time was wrong on the dedicated android phone I use. Second attempt after fixing the time issue, I used Mizar and Sirius. Mizar was miles out until I corrected, Sirius also pretty far out but after that every target was spot on! Spent the rest of the session touring a few objects I've recently observed in a bigger scope for a comparison of the experience. A fun 3 hour session!

Just before I packed up, I fired up Stellarium on the phone to see if I could connect the scope. There was an error with Stellarium having no data to download additional star charts which was not an issue, but although it said the mount was connected and knew where it was in the sky (helpfully shows you on the map) it did have additional sync errors.

Another story for another day, but definitely something I want to play around with! Anyone who has experience of using Stellarium mobile with the AZ-GTi, I would be glad to hear about it. 

Edited March 24, 2022 by badhex

[Elp]

9 hours ago, AstroNebulee said:

Just got in from grabbing 2 hours worth of data on M101 tonight, so pleased to be back out under a moonless, windless, clear night sky even if the transparency was rubbish. Couldnt really make Virgo out atall and Leo was washy. 

And quick couple of screenshots, guiding was very good too using multistar guiding. 

Hoping to grab more data on it moro night if it stays clear. 

 

Funny that, I was doing this on Tuesday, yours shows good detail for two hours, I did 60 mins L, 45 R,G,B, 30 Ha and it still seems dim after processing. Guess my issue is time now, need to do at least the same again. Ha I'm guessing around 3-4 hours should do (it reveals the bright red globules in the dust lanes).

[Elp]

As a general rule for camera settings:

1. If you want lower read noise work towards unity gain or higher, there are limited gains going way beyond unity.

2. Lower than unity gain or closer to zero gives you better full well depth (larger full well depth, the longer photons can keep hitting a pixel before it becomes fully saturated). This also gives you better dynamic range in bit depths (more bits = more distinct levels of grey/colour can be defined).

Both these terms work opposite to each other (ie higher gain = lower read noise, less FWD and DN, lower gain = higher read noise, more FWD and DN in general). Tbh I don't really see that much difference (for my cam anyway), the differentiating factor is integration time and not capturing light pollution.

Edited March 24, 2022 by Elp

[bomberbaz]

11 hours ago, AstroNebulee said:

Just got in from grabbing 2 hours worth of data on M101 tonight, so pleased to be back out under a moonless, windless, clear night sky even if the transparency was rubbish. Couldnt really make Virgo out atall and Leo was washy. 

And quick couple of screenshots, guiding was very good too using multistar guiding. 

Hoping to grab more data on it moro night if it stays clear. 

 

excellent guiding that pal, what exposure and gain you using?

[RayWUK]

13 hours ago, AstroNebulee said:

Just got in from grabbing 2 hours worth of data on M101 tonight, so pleased to be back out under a moonless, windless, clear night sky even if the transparency was rubbish. Couldnt really make Virgo out atall and Leo was washy. 

And quick couple of screenshots, guiding was very good too using multistar guiding. 

Hoping to grab more data on it moro night if it stays clear. 

 

What camera were you using for this? I'm thinking of selling on my Canon 600D (Mod) and getting a dedicated camera. Only thing stopping me at present is which one, 183MC, 553MC or 294MC. They all have their merits, i kind of like the square format of the 553MC. That guiding you have is something i can only dream about at present. Would you mind sharing your settings?

Edited March 24, 2022 by RayWUK

[AstroNebulee]

5 hours ago, Elp said:

Funny that, I was doing this on Tuesday, yours shows good detail for two hours, I did 60 mins L, 45 R,G,B, 30 Ha and it still seems dim after processing. Guess my issue is time now, need to do at least the same again. Ha I'm guessing around 3-4 hours should do (it reveals the bright red globules in the dust lanes).

Thank you. That isn't 2 hours on M101 it's just a screenshot from one sub on the asiair app. I should of added it was just screenshots, sorry. 

I'm hoping to get more on it tonight if it stays clear, no wind again. Would like to get more on it, there's some interesting galaxies around it namely ngc 5474.

Like you say more integration time in Ha will get the results youd like, good luck 👍

Edited March 24, 2022 by AstroNebulee

[AstroNebulee]

2 hours ago, bomberbaz said:

excellent guiding that pal, what exposure and gain you using?

Thank you, though my guiding was more generally around 1"  but kept lowering to that value, so well happy. 

With my zwo 294mc pro I was using 120 gain which is the unity and 180 sec subs. 

[bomberbaz]

3 minutes ago, AstroNebulee said:

Thank you, though my guiding was more generally around 1"  but kept lowering to that value, so well happy. 

With my zwo 294mc pro I was using 120 gain which is the unity and 180 sec subs. 

Sorry should have been specific, I  meant on your guide camera. I am assuming your not using a pro camera for guiding.

[AstroNebulee]

7 hours ago, RayWUK said:

What camera were you using for this? I'm thinking of selling on my Canon 600D (Mod) and getting a dedicated camera. Only thing stopping me at present is which one, 183MC, 553MC or 294MC. They all have their merits, i kind of like the square format of the 553MC. That guiding you have is something i can only dream about at present. Would you mind sharing your settings?

Hi Ray 

Thank you. My camera is a zwo 294mc pro. There are plenty of threads on here about choosing a dedicated astro camera on here. I was umming and ahhhing about those 3 until I got the 294mc pro. The thing that swayed my choice was the larger sensor. The amp glow doesn't bother me as its very easily calibrated out with darks. I'm really happy with my choice and suits my scope stats. Do your research and ask on here what would suit your setup and how you want it.

That is the best guiding I've ever had, no wind and the meshing of the Dec motor gears proved this. I must do the same to the RA motor. I shall share screenshots of my settings pages when I'm hopefully imaging tonight. 

I do my guiding calibration on the target I'm imaging and multistar guiding, choosing a guide star around 3 hfd and my guidescope nicely focused. My guide speed is 0.9x, generally RA aggression 40-45 and dec is 55. Gain of guidescope is around 60 and exposure is 2 secs. I'll double check my calibration step settings but think it's 2000ms, max Dec & RA duration is 500ms. I believe my guide stability settings are 4" for 3 seconds. Will take screenshots later (hopefully) 

Cheers 

 

Lee 

Edited March 24, 2022 by AstroNebulee

[AstroNebulee]

19 minutes ago, bomberbaz said:

Sorry should have been specific, I  meant on your guide camera. I am assuming your not using a pro camera for guiding.

Ahh sorry Steve (I'm a bit thick anyway haha) No I'm using my zwo asi120mc-s for guiding on the zwo 30mm f4 guidescope. My gain is around 60 and exposures are 2 secs. Though my gain can range from 50-70 depending on the quality of the sky. 

Cheers 

Lee 

Edited March 24, 2022 by AstroNebulee

[AstroNebulee]

5 hours ago, badhex said:

Was out with the AZ-GTi and ZS73 last night for the first time since last November! 

I had momentarily forgotten several things, like how much additional stuff you have to do for setup vs completely manual alt-az. That said, the manual alt-az I've been using recently was a Skytee-2 and EQ-6 tripod which I did not miss carrying up two flights of stairs. 

I luckily plonked down the tripod in spot where it was completely level, and after setting everything else up including first proper use of the Celestron battery I bought last year, I started north-level alignment which took two attempts: the first slew being completely off as the time was wrong on the dedicated android phone I use. Second attempt after fixing the time issue, I used Mizar and Sirius. Mizar was miles out until I corrected, Sirius also pretty far out but after that every target was spot on! Spent the rest of the session touring a few objects I've recently observed in a bigger scope for a comparison of the experience. A fun 3 hour session!

Just before I packed up, I fired up Stellarium on the phone to see if I could connect the scope. There was an error with Stellarium having no data to download additional star charts which was not an issue, but although it said the mount was connected and knew where it was in the sky (helpfully shows you on the map) it did have additional sync errors.

Another story for another day, but definitely something I want to play around with! Anyone who has experience of using Stellarium mobile with the AZ-GTi, I would be glad to hear about it. 

Really pleased you got your az gti out at last and that is a long time since it's last outing but sounds like you had a really good tour of the night sky last night indeed.👍😊 I don't use stellarium for my mount though. 

[bomberbaz]

2 hours ago, AstroNebulee said:

Ahh sorry Steve (I'm a bit thick anyway haha) No I'm using my zwo asi120mc-s for guiding on the zwo 30mm f4 guidescope. My gain is around 60 and exposures are 2 secs. Though my gain can range from 50-70 depending on the quality of the sky. 

Cheers 

Lee 

Interesting gain, I am using around 250. Wonder if there are too many stars that is affecting tracking accuracy as a result of this.

Are you still managing multi star tracking easily enough Lee?

Cheers, steve

[AstroNebulee]

34 minutes ago, bomberbaz said:

Interesting gain, I am using around 250. Wonder if there are too many stars that is affecting tracking accuracy as a result of this.

Are you still managing multi star tracking easily enough Lee?

Cheers, steve

It's still guiding well on the multistar guiding and picked out around 10 or so stars to guide on plus the main one.

You could always try a lower gain on yours and see how many stars it picks up. With your gain at 250 are the stars quite bloated? 

This screenshot is from a few weeks ago and before I refocused my guidescope so the stars are a little off and the hfd of the star a bit high but this is with gain 60. Note only using one star to guide in the screenshot but using multistar now. The guidestar in the box in top left should have the red graph bit at a point and not flattened off. 

Cheers 

 

Lee 

 

Edited March 24, 2022 by AstroNebulee

[bomberbaz]

26 minutes ago, AstroNebulee said:

It's still guiding well on the multistar guiding and picked out around 10 or so stars to guide on plus the main one.

You could always try a lower gain on yours and see how many stars it picks up. With your gain at 250 are the stars quite bloated? 

This screenshot is from a few weeks ago and before I refocused my guidescope so the stars are a little off and the hfd of the star a bit high but this is with gain 60. Note only using one star to guide in the screenshot but using multistar now. The guidestar in the box in top left should have the red graph bit at a point and not flattened off. 

Cheers 

 

Lee 

 

 

You have just made me think, I actually altered the focus last night when moving the system around and forgot to check focus again later before using the kit.

Anyway, I will drop my gain and recheck focus before my next run to see if that helps. Looking outside that is unlikely to be tonight though, lol.

Steve

[AstroNebulee]

3 hours ago, bomberbaz said:

You have just made me think, I actually altered the focus last night when moving the system around and forgot to check focus again later before using the kit.

Anyway, I will drop my gain and recheck focus before my next run to see if that helps. Looking outside that is unlikely to be tonight though, lol.

Steve

Hopefully you can get your set up outside soon to test it all out, good luck Steve. 

 

Cheers 

Lee 

[AstroNebulee]

@RayWUK @bomberbazhere are my quick screenshots of settings for tonight.

 

Edited March 24, 2022 by AstroNebulee