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Skywatcher Star Adventurer


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My major concern right now is polar alignment.

With some work, I can get it to align quite precisely, the polar scope is very nice, the knobs are a bit too wobbly, but in the end, it's doable; the problem is that whenever I touch my camera(s), the alignment goes off, sometimes by a lot.  Last time I used it, my images had a huge drift, almost 2 degrees over 5/6 hours!

I use it with a slighly high focal length (200mm), and I wish to go further in the future, around 300/350mm, but unless I solve the polar alignment issue, it's gonna be tough.

I use the L bracket, so you can avoid a few problems (you don't need to mount the cameras after polar alignment), but when I point them it' still the same, I loose much of the polar alignment precision anyway.

When using the L bracket you can still look through the polar scope, so I was thinking of a different polar alignment workflow: first a rough polar alignment, then pointing the cameras, then a precise polar alignment, but if you rotate the RA axis, you loose your reference to the exact position of Polaris, and you don't know where it should actually be.

 

Has anyone found out how to improve polar alignment? 

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I load everything up and then polar align, don't loosen the locking screws off as you can still adjust it with them tightened.

Have you checked the the polar reticle is centred ? once PAd if you loosen the clutch and rotate it Polaris should follow the circle

When up and running you can check that Polaris is tracking around the circle while you're imaging and tweak it a bit and not worry too much about where on the clock face it is.

I use a 300mm lens on mine.

Dave

 

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10 minutes ago, Davey-T said:

I load everything up and then polar align, don't loosen the locking screws off as you can still adjust it with them tightened.

Do you mean the locking screw on the wedge? If so, I always tight that one a lot, to avoid any backlash, I always do my adjustment with that tightened up.

10 minutes ago, Davey-T said:

Have you checked the the polar reticle is centred ? once PAd if you loosen the clutch and rotate it Polaris should follow the circle

I need to recheck it, but it was fine last time I looked it. Not 100% accurate, but pretty close.

10 minutes ago, Davey-T said:

When up and running you can check that Polaris is tracking around the circle while you're imaging and tweak it a bit and not worry too much about where on the clock face it is.

Well, I was hoping to polar align after pointing my cameras, so I'd need to know where on the clock face it should be. But I see your point, I might just polar align before, and then check that polaris is still roughly on the same place.

I'm starting to think it might not just be a polar alignment problem, but a balancing issue, affecting tracking speed. 2 degrees is a hell of a misalignment, it's almost the whole field of view of the polar scope!

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35 minutes ago, GuLinux said:

 

Well, I was hoping to polar align after pointing my cameras, so I'd need to know where on the clock face it should be. But I see your point, I might just polar align before, and then check that polaris is still roughly on the same place.

 

It doesn't stay in the same place it moves round anti clockwise during the night, you just need to keep it going round the circle.

Dave

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Just now, Davey-T said:

It doesn't stay in the same place it moves round anti clockwise during the night, you just need to keep it going round the circle.

Dave

Yes, what I mean is checking the position with a "polar finder" app.

Maybe I'll just write my own version of it, but accepting an "offset" after you rotate the RA axis :p

 

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  • 4 months later...

Hi All,

I just wanted to give my 2 pennies worth and hope its helps anyone with the SWSA. I have a QHY polemaster, which, along with Backyard EOS are probably the 2 most useful value for money bits of kit I have purchased since getting into Astrophotography around 12 months ago. I currently own a Celestron CGEM mount, and Skywatcher ED80 Scope, plus the SWSA, which I purchased for the American eclipse in August. 

The point of this post, and I hope I'm not trying to teach my granny to suck eggs, but if you have a polemaster, they now do an adaptor for the SWSA. I have just ordered one and will let you all know how it goes. You can load and Balance your equipment, and then polar align without dismantling.

I hope this helps.

Regards John

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Anyone had their mount Hypertuned?

Lately i can't seem to reliably get >60s subs with my kit. I'm around or more likely just under 50% of the mount's 5kg payload capacity, too.

I'm about to send mine off, as I've positive feedback from users with other EQ mounts.

Edited by 8472
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8472, Check that the pilar that the 2 az adjuster's work against is secure. I found on mine it was loose so it never had a positve az 'lock'. You will find underneath the wedge is a screw that inside holds a pilar stud. You have to just put some lock thread on this and do it it up. It will not come loose again. It's a bit of a pain as you have to dismantle the wedge to get to it. But a least no special tools are required. I also had a proplen with the alitude locking lever and had to replace that with a new bolt, spacer and hand wheel. A much better and poitive solution.

Edited by HughP
Grammar
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21 minutes ago, HughP said:

8472, Check that the pilar that the 2 az adjuster's work against is secure. I found on mine it was loose so it never had a positve az 'lock'. You will find underneath the wedge is a screw that inside holds a pilar stud. You have to just put some lock thread on this and do it it up. It will not come loose again. It's a bit of a pain as you have to dismantle the wedge to get to it. But a least no special tools are required. I also had a proplen with the alitude locking lever and had to replace that with a new bolt, spacer and hand wheel. A much better and poitive solution.

Hmm, not something I thought to look at, tbh. I'm going to have to investigate this when I get in.

Thanks for that!

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I have had mine hypertuned but not used it yet as I only use it when I go to dark sites for widefield imaging.

Whilst in France in June I was getting 450s un-guided and the attached shows how good this little mount is and this wasn't hypertuned then, so how good will it be now.

The image is unprocessed (Just reduced in size for here) at ISO 160 F2.8 14mm on my Nikon D800, it wasn't even well balanced as I had left the counter weights at home.

The only thing I always do is use my Polemaster for a polar alignment

GOOD_LIGHT_450s_160iso_2-8_20170617-23h37m57s507ms.jpg

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1 hour ago, Jkulin said:

I have had mine hypertuned but not used it yet as I only use it when I go to dark sites for widefield imaging.

Whilst in France in June I was getting 450s un-guided and the attached shows how good this little mount is and this wasn't hypertuned then, so how good will it be now.

The image is unprocessed (Just reduced in size for here) at ISO 160 F2.8 14mm on my Nikon D800, it wasn't even well balanced as I had left the counter weights at home.

The only thing I always do is use my Polemaster for a polar alignment

GOOD_LIGHT_450s_160iso_2-8_20170617-23h37m57s507ms.jpg

Nice image. That's at the super wide end of the spectrum, so very forgiving of alignment and tracking. I'm at the other extreme, with 576mm (crop sensored) fl.

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  • 2 months later...
On 12/01/2018 at 19:14, 8472 said:

From that site:

"Below is a cropped single 10 minute (602 seconds to be precise) or our Star Adventurer with a 200mm EF lens (=320mm focal length  due to crop factor)"

Gah!  I hate it when people suggest that using a crop sensor somehow changes the focal length.  How do they imagine that works?  Does it somehow magically introduce another lens?

I do like the counterweight made from three drink cans though.  That's rather neat and handy if you want to take stuff on holiday without weighing yourself down with lumps of steel.

James

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  • 5 months later...

Hi folks, feedback required on problems with star trailing on my SSA set up. Trying to get the set up to work so I can get out into the country dark sites. I have an ASI1600MC mounted on a TS Optics 60mm with flattener (focal length 260mm). I have taken time to polar align, checked that it does a full rotation in 24 hours but anything over about 30 sec subs and I get star trailing. Balancing is not easy and the camera and scope looks quite weighty for what is a rather flimsy set up.

Any feedback welcome on how to get longer subs that others seem to achieve. 

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You have almost exactly my setup ? same scope, same mount, same camera.. only difference is I have the ASI 1600MM (MONO/non cool), with a filter wheel :)

 

First, have you checked that the polarscope is correctly calibrated? You can check the Star Adventurer manual for details, or this website: http://www.myastroscience.com/polarscopecalibration

Most importantly though polar alignment can be ruined by even the smallest touches. What I did to improve overall stability was to lubricate with grease the equatorial wedge (I dismantled it to be able to access the internals), tighten the two small screws that limit the azimuth movement (the allen ones), and tighten the other screws (altitude and azimuth lock) as much as possible when polar alignment is finished.

I also try to never tighten too much the RA lock until I finished literaly *everything* and I'm ready to image. Continuously screwing/unscrewing that lock eventually causes to loose polar alignment.

 

Also, very important (but you're probably already doing it) you should polar align with the telescope already on the star adventurer with the L bracket, and use the illuminator with the adapter.

Balancing is hard, and that setup is already pushing the mount to the limit. I plan to add an additional counterweight to help this, but anyway by pushing the counterweight to the end of the shaft, and lowering the L bracket, I can get everything quite balanced, even with some little slack.

Declination balancing is easier if you add the extra tube section to the scope, this way more weight can go to the lens part.

 

When I do polar alignment properly, I can go up to ~2 minutes. Not a lot, but with these cameras you'd better stack loads of frames, rather than try to increase exposure time.

Edited by GuLinux
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23 minutes ago, GuLinux said:

You have almost exactly my setup ? same scope, same mount, same camera.. only difference is I have the ASI 1600MM (MONO/non cool), with a filter wheel :)

 

First, have you checked that the polarscope is correctly calibrated? You can check the Star Adventurer manual for details, or this website: http://www.myastroscience.com/polarscopecalibration

Most importantly though polar alignment can be ruined by even the smallest touches. What I did to improve overall stability was to lubricate with grease the equatorial wedge (I dismantled it to be able to access the internals), tighten the two small screws that limit the azimuth movement (the allen ones), and tighten the other screws (altitude and azimuth lock) as much as possible when polar alignment is finished.

I also try to never tighten too much the RA lock until I finished literaly *everything* and I'm ready to image. Continuously screwing/unscrewing that lock eventually causes to loose polar alignment.

 

Also, very important (but you're probably already doing it) you should polar align with the telescope already on the star adventurer with the L bracket, and use the illuminator with the adapter.

Balancing is hard, and that setup is already pushing the mount to the limit. I plan to add an additional counterweight to help this, but anyway by pushing the counterweight to the end of the shaft, and lowering the L bracket, I can get everything quite balanced, even with some little slack.

Declination balancing is easier if you add the extra tube section to the scope, this way more weight can go to the lens part.

 

When I do polar alignment properly, I can go up to ~2 minutes. Not a lot, but with these cameras you'd better stack loads of frames, rather than try to increase exposure time.

Hi  Many thanks for getting back to me. The first thing I need to do, as you suggest, is to check the polarscope calibration. It was Ok some time ago, but I have made a small 90 degree lens so that I can more easily view polar alignment, instead of standing on my head, however, I have to push this onto the end of the polar scope and I may have put it out of calibration. 

Not sure what you mean by adding an extra tube section to the scope to help Dec balancing, any chance you could post an image of your set up?

I am using the short vee plate that comes with the TS60 scope and this leads to some difficulty in balancing the scope.

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There's an extra white ring in the scope package, you should unscrew the focuser, and add the ring to the tube. It's an extension.IMG_20180824_221049.thumb.jpg.e5891c65421374855962a2ff053f843a.jpg

 

I'm using the same plate as well, but I moved the attach point so it's closer to the focuser (and with said extension you also get some extra room).

I have to keep the focuser on the top side (reversed) in order to get the balance point as close to the focuser as possible:

IMG_20180824_221416.thumb.jpg.fa59581e6d49c649f8289097e5348bd5.jpg

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23 minutes ago, GuLinux said:

There's an extra white ring in the scope package, you should unscrew the focuser, and add the ring to the tube. It's an extension.IMG_20180824_221049.thumb.jpg.e5891c65421374855962a2ff053f843a.jpgimageproxy.php?img=&key=bdf8b2134cef9d8b

 

I'm using the same plate as well, but I moved the attach point so it's closer to the focuser (and with said extension you also get some extra room).

I have to keep the focuser on the top side (reversed) in order to get the balance point as close to the focuser as possible:

IMG_20180824_221416.thumb.jpg.fa59581e6d49c649f8289097e5348bd5.jpg

Very many thanks for that, most helpful. I wondered what that extra tube in the case was for! Tomorrow I will check the polarscope calibration and extend the tube. thanks again. Alec

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Hi GuLinux

Thanks for your help. Extended the tube length today, improved balance as you suggested. Checked the polar scope calibration, not far out, but I had a fiddle and improved it slightly. Can't get it any better than the end result.

Set up in the garden an hour ago and ran into an unforeseen problem. The additional tube length had changed the focus point and I can't wind the focuser in enough of achieve focus!! What a hobby this is!!!!

Obviously out set ups are similar, but I don't have the filter wheel as I have the ASI1600MC. I have the TSRED279 reducer/flattener in the chain and a Moonlite focuser. Spacers bring everything to 70mm from the sensor to the reducer/flattener.

Not sure I have any option but to remove the scope tube extender?

Any comments? Thanks

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6 minutes ago, alcol620 said:

Hi GuLinux

Thanks for your help. Extended the tube length today, improved balance as you suggested. Checked the polar scope calibration, not far out, but I had a fiddle and improved it slightly. Can't get it any better than the end result.

Set up in the garden an hour ago and ran into an unforeseen problem. The additional tube length had changed the focus point and I can't wind the focuser in enough of achieve focus!! What a hobby this is!!!!

Obviously out set ups are similar, but I don't have the filter wheel as I have the ASI1600MC. I have the TSRED279 reducer/flattener in the chain and a Moonlite focuser. Spacers bring everything to 70mm from the sensor to the reducer/flattener.

Not sure I have any option but to remove the scope tube extender?

Any comments? Thanks

Mmh, that is weird... in my setup, having the filter wheel, I should get more further away from the focus than you do.. And yet I can focus with the tube extension without problem.

I have the same reducer as well, so that shouldn't be the issue.

Only one thing pops to my mind: you mentioned a "Moonlite focuser"? Meaning, you have the refractor focuser PLUS an extra focuser?

If that's the case, no wonder you can't focus.. I would get rid of that, the TS60 native focuser is already pretty good

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1 hour ago, GuLinux said:

Mmh, that is weird... in my setup, having the filter wheel, I should get more further away from the focus than you do.. And yet I can focus with the tube extension without problem.

I have the same reducer as well, so that shouldn't be the issue.

Only one thing pops to my mind: you mentioned a "Moonlite focuser"? Meaning, you have the refractor focuser PLUS an extra focuser?

If that's the case, no wonder you can't focus.. I would get rid of that, the TS60 native focuser is already pretty good

Apologies, getting in a muddle as always. The focuser is the one that comes with the TS60 but it has a stepper motor on it. Its my 120ED that has the moonlite. Will take an image tomorrow to illustrate the set up. i would have thought the distances would be the same. The distance requirement of the reducer should make the distances the same.

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