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How to improve tracking of Star Adventurer (with/without Guiding)

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#1 mxcoppell

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Posted 28 November 2017 - 12:00 AM

Current setup: 

 

  • Sky-Watcher Star Adventurer
  • Nikon D500 (Stock)
  • Nikon 70-200mm f2.8 II
  • Orion 50mm Guiding Scope
  • Orion Starshoot Autoguider
  • Manfrotto Aluminum Tripod  (with 20-lbs dumbbell added weight)

 

Dec bracket and the counter weight kit are deployed. I use 2 ball heads, one for the D500+70-200/2.8 on the rotate-able geared head side, the other ball head installed on the counter weight bar side for the guiding scope. Overall, I don't think this setup exceeds the payload limitation of the Star Adventurer. 

 

For polar alignment, pretty sure I got it very well before the shooting starts. Tested the tracking without guiding with focal length at 200mm, 30-second shot looks pretty good (frame center, stars look round and solid). But for 45-second or 60-second shots, the star trails are very obvious. With PHD2 guiding, the guiding chart looks pretty smooth if I don't touch the setup. But when taking test shots, I still can only get solid stars at 30-seconds - 45-second and 60-second have obvious trails. 

 

After tracking for an hour or so, I went back to check the polar scope - Polaris didn't wander off its path on the circle in the polar scope. So I would assume the PA is still good.

 

From the PHD2 guiding chart (RA-only), I don't see the guiding adjustment getting worse. It looks pretty smooth. Next time I will capture a guiding chart to post here.

 

I don't have any ideas about how to improve this other than more carefully checking the tripod level. 

 

Another thing bothered me is that - with guided tracking, isn't it should be much better? I am thinking I should be able to take 120-second sub-shot without guiding and 300-second sub-shot with guiding at 200mm (or 280mm with TC1.4). Am I expecting too much?

 

My goal is to use my existing photo gears - without using telescopes and big tracking mounts, to see where the limits are.

 

At last, not many Nikon D500 samples on CN forum, here are a few of mine shot 2017/10 and 2017/11 at Fort Griffin Historical Site (Class-2 dark site).

 

MX-20171118-233808-20171127232836.jpg

"Orion Rises Above Fort Griffin"

 

MX-20171127-193436-20171127232859.jpg

M31, 30s/200mm/f2.8/iso3200/64-light/25-dark/25-bias


Edited by mxcoppell, 28 November 2017 - 01:26 AM.

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#2 SKYGZR

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Posted 28 November 2017 - 01:01 AM

What you have posted looks pretty good..If you're looking to improve..you might want to tear it apart, & hypertune the thing...might help, might not...


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#3 mxcoppell

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Posted 28 November 2017 - 01:16 AM

@SKYGER,

 

Thanks for the comment! Actually I followed the user manual and checked the SA. Not sure it could go back to the original precision after reassembling. laugh.gif

 

I do read on the internet that people are able to get solid stars without guiding at 120-seconds. 

With guiding, single exposure could go up to 5 minutes. 

 

Or using the M31 as example, could I get more details (colors, layers) if I take more 30s light frames with the same configuration?


Edited by mxcoppell, 28 November 2017 - 01:18 AM.


#4 Jim Waters

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Posted 28 November 2017 - 01:52 AM

I am able to get ~240" with a 200mm lens.  Balance and PA are key...!  Also being level and a very good tripod.


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#5 Jim Waters

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Posted 28 November 2017 - 01:53 AM

What you have posted looks pretty good..If you're looking to improve..you might want to tear it apart, & hypertune the thing...might help, might not...

Can you point to any hypertune literature?



#6 Cajundaddy

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Posted 28 November 2017 - 02:05 AM

Fundamentals:

* PA must be very precise

* For precise tracking your total payload should be roughly 50% of rated payload for your mount.

* Rock solid tripod weighted and set low to the ground or on a permanent pier.

* Carefully balance your payload and counterweights.

 

With all of these things in place you should be able to shoot much longer subs without trailing.


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#7 bobzeq25

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Posted 28 November 2017 - 10:30 AM

@SKYGER,

 

Thanks for the comment! Actually I followed the user manual and checked the SA. Not sure it could go back to the original precision after reassembling. laugh.gif

 

I do read on the internet that people are able to get solid stars without guiding at 120-seconds. 

With guiding, single exposure could go up to 5 minutes. 

 

Or using the M31 as example, could I get more details (colors, layers) if I take more 30s light frames with the same configuration?

Those are pretty nice.

 

You've got it, about taking more subexposures.

 

Total imaging time is crucial, more important than getting the subexposure time exactly "right" (whatever that is).

 

People can argue whether 30X60 seconds is better than 60X30 seconds.  But 60X60 seconds will beat either.

 

The M31 looks like it could use a boost in saturation, there's almost certainly more color there.

 

Are you doing flats?

 

Camera trackers are great, but they're low cost, they can be pretty variable with regard to tracking ability.  People's experiences with a certain model vary.


Edited by bobzeq25, 28 November 2017 - 10:36 AM.

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#8 SKYGZR

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Posted 28 November 2017 - 05:26 PM

 

What you have posted looks pretty good..If you're looking to improve..you might want to tear it apart, & hypertune the thing...might help, might not...

Can you point to any hypertune literature?

 

None that I know of...yet, if someday I decide to play with mine, I may take some pic's & do a write up..yet right now no real intention..



#9 mxcoppell

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Posted 28 November 2017 - 05:48 PM

I am able to get ~240" with a 200mm lens.  Balance and PA are key...!  Also being level and a very good tripod.

Jim. Don't think I got a chance to thank you for the hint about setting up the RA-only guiding for SA.  Thanks!

 

240s is with guiding right? That's amazing. 

 

Even with the counter weight, I find it's hard to get absolutely balance with D500+70-200, guiding scope/camera. But I adjusted the "starting" position of the PA (where I can set the PA scope cross vertically in the view). By this way, the counter weight is at the bottom and the heavies part of camera and lens is at the top. The line from the counter wight to the camera+lens only tilts about 30 degrees from vertical line. So basically the weight is on the top. I will think about some other ideas. 

 

For PA, after I set the initial position of the cross in the view vertically (following SA's manual), I always set the Polaris exactly at the spot shown by the PA Align app. I think my basics of PA is correct. Otherwise there is no way I could even get 30s shots at 200mm.

 

For SA, the headache is manual Go-To - no matter how care I was, I suspects it impacts the already established PA and tracking. I do go back to the polar scope to see if the Polaris is moved away from the polar scope cycle. How do you solve this problem when adjusting camera+lens to point to the target?

 

Here is another attempt I did last month at Fort Griffin.

 

MX-20171127-193509-20171127232849.jpg

M45, 30s/200mm/f4.0/iso1600/80-light/25-dark/25-bias


Edited by mxcoppell, 28 November 2017 - 06:07 PM.

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#10 mxcoppell

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Posted 28 November 2017 - 05:58 PM

 

You've got it, about taking more subexposures.

 

Total imaging time is crucial, more important than getting the subexposure time exactly "right" (whatever that is).

 

People can argue whether 30X60 seconds is better than 60X30 seconds.  But 60X60 seconds will beat either.

 

The M31 looks like it could use a boost in saturation, there's almost certainly more color there.

 

Are you doing flats?

 

Camera trackers are great, but they're low cost, they can be pretty variable with regard to tracking ability.  People's experiences with a certain model vary.

 

That's what I definitely would try next by adding the number of light frames. 30s still seems a little too short - for bright subjects it might be okay, but for faint subjects longer exposure sounds better (for example, shooting nebulas when the camera is astro-modified).

 

I like your 30x60, 60x30, and 60x60 example, yes! I want 60x60! LOL

 

I tried boost M31 left & right, but can't see the rich color layers of it. I think 64 light frames is not enough. 

 

About flats, I always think it's not that useful. Could you share if shooting flats is really necessary? 

 

D500+70-200mm probably is at the limit of SA. My ultimate goal is to put the 200-500/5.6 in use, haven't found the proper mount yet.

 



#11 mxcoppell

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Posted 28 November 2017 - 06:04 PM

Fundamentals:

* PA must be very precise

* For precise tracking your total payload should be roughly 50% of rated payload for your mount.

* Rock solid tripod weighted and set low to the ground or on a permanent pier.

* Carefully balance your payload and counterweights.

 

With all of these things in place you should be able to shoot much longer subs without trailing.

Yes, those are the devils!

 

Cajundaddy, could you share your experience about the following:

 

- How do I know if PA is precise enough? Normally I do a 30s shot after the PA and tracking started, then check in BackyardNIKON to see if the stars are solid.

- Total payload amount will be an issue, with D500+70-200mm and guiding scope/camera, I think it's at 80% of 11lbs. But I tried to start the shooting position when camera is at the very top of the RA axle. 

- Yes, I got the 20lbs dumbbell hanging under the tripod - but I definitely could lower the tripod next time. I will show a picture of my setup (need to dig into the piles of pictures).

- Maybe a second counter weight bar is required, but will it introduce problem to the totally payload weight limitation?



#12 bobzeq25

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Posted 29 November 2017 - 12:42 AM

Hope this doesn't come across as offensive, I'm just trying to help.

 

Downloaded your jpg, put it in Pixinsight.  Silly thing to do, but there's a point.  Boosted color saturation.  No attempt was made to do it well, just wanted to show you it's there.

 

Honestly, it's not the limited number of frames, it's processing.  Even with terrestrial experience, it takes time to learn astro processing.  What more total imaging time does for you is lower the noise, improve the all important signal to noise ratio.

 

Flats are perhaps _the_ most important calibration frames.  Not only do they correct vignetting and dust, they smooth out uneven pixel response.  Essential.  I always do bias and flats.  Don't do darks, have low thermal noise cameras.

 

The background on both M31 and M42 looks like the black point was raised too far.  People tend to do that when they don't shoot flats, to smooth the background out.  .

 

Here's how you get to a reasonable subexposure time (which depends on your skies).  Shoot a frame, look at the histogram on the back of your camera.  Do what it takes to get it about 1/3 over from the left.  Good enough.

 

You could probably benefit from this book, which discusses these issues and much more, in detail.

 

https://www.amazon.c...tography manual

 

M31 add color Added.jpg


Edited by bobzeq25, 29 November 2017 - 12:50 AM.

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#13 Jim Waters

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Posted 29 November 2017 - 01:07 AM

 

I am able to get ~240" with a 200mm lens.  Balance and PA are key...!  Also being level and a very good tripod.

Jim. Don't think I got a chance to thank you for the hint about setting up the RA-only guiding for SA.  Thanks!

 

240s is with guiding right? That's amazing. 

 

Even with the counter weight, I find it's hard to get absolutely balance with D500+70-200, guiding scope/camera. But I adjusted the "starting" position of the PA (where I can set the PA scope cross vertically in the view). By this way, the counter weight is at the bottom and the heavies part of camera and lens is at the top. The line from the counter wight to the camera+lens only tilts about 30 degrees from vertical line. So basically the weight is on the top. I will think about some other ideas. 

 

For PA, after I set the initial position of the cross in the view vertically (following SA's manual), I always set the Polaris exactly at the spot shown by the PA Align app. I think my basics of PA is correct. Otherwise there is no way I could even get 30s shots at 200mm.

 

For SA, the headache is manual Go-To - no matter how care I was, I suspects it impacts the already established PA and tracking. I do go back to the polar scope to see if the Polaris is moved away from the polar scope cycle. How do you solve this problem when adjusting camera+lens to point to the target?

 

Here is another attempt I did last month at Fort Griffin.

 

attachicon.gifMX-20171127-193509-20171127232849.jpg

M45, 30s/200mm/f4.0/iso1600/80-light/25-dark/25-bias

 

Thanks.  The 240" subs may be a once or twice time thing.  I was lucky.  Balancing is key.  I use a Tripod Lens Mount Ring on my Canon lens.  This really helps getting the balance right.  I use 1 or 2 Star Adventurer counter weights on the DEC axis and spend the time to get the correct balance.  As for PA, its critical.  I level the tripod / mount and do an initial PA.  I then move the RA / DEC and orient the camera so the target is framed the way I want.  I then redo PA taking the time to get everything correct.  I then check to make sure the camera is still on target.  If necessary I readjust everything and redo PA.


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#14 Betelgeuze

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Posted 29 November 2017 - 11:21 AM

Mine seems to behave better unguided, as guided..  undecided.gif

 

I have done 4 minutes subs unguided, and have nice round stars.. (200mm @ ap-c censor)

 

And last week I tried to guide the Star Adventurer with PHD2 + 50mm finder guider for the first time,

only 2 minutes subs due light pollution, but got slightly elongated stars...  bawling.gif  probably to much wind and user error...  wink.gif

 

Be sure to check the calibration of your polar scope before using, and to careful lock the RA-clamp after pointing your camera.

 

Maybe next time I'm gonna try the Polemaster with the Star Adventurer,

but i'm afraid locking the RA-clamp got a bad influence on precise polar alignment.

 

Plus.. with guiding/guidescope and polemaster and the need of a laptop,  it isn't a really portable set anymore..

 

p.s. nice picture Orion @ Fort Griffin. waytogo.gif


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#15 Cajundaddy

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Posted 29 November 2017 - 11:48 AM

 

Fundamentals:

* PA must be very precise

* For precise tracking your total payload should be roughly 50% of rated payload for your mount.

* Rock solid tripod weighted and set low to the ground or on a permanent pier.

* Carefully balance your payload and counterweights.

 

With all of these things in place you should be able to shoot much longer subs without trailing.

Yes, those are the devils!

 

Cajundaddy, could you share your experience about the following:

 

- How do I know if PA is precise enough? Normally I do a 30s shot after the PA and tracking started, then check in BackyardNIKON to see if the stars are solid.

- Total payload amount will be an issue, with D500+70-200mm and guiding scope/camera, I think it's at 80% of 11lbs. But I tried to start the shooting position when camera is at the very top of the RA axle. 

- Yes, I got the 20lbs dumbbell hanging under the tripod - but I definitely could lower the tripod next time. I will show a picture of my setup (need to dig into the piles of pictures).

- Maybe a second counter weight bar is required, but will it introduce problem to the totally payload weight limitation?

 

I am old school AP and I use the drift-align method to finalize my polar alignment for imaging.  I suppose you could do that in Live View at 10x but I have not used the Star Adventurer so I am not sure if it offers the precision movement needed to get the mount dead-nuts polar aligned.  There are software solutions now that make things much easier so if you are imaging with laptop control that is probably your best method.

 

Weight and balance is the other niggling issue and once you get this right, long exposure subs become much more consistent.

 

The lower the tripod is to the ground, the less it will be influenced by wind and flexure so I like to get it down pretty low unless we are out in the dusty desert.


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#16 mxcoppell

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Posted 29 November 2017 - 06:40 PM

Hope this doesn't come across as offensive, I'm just trying to help.

 

Downloaded your jpg, put it in Pixinsight.  Silly thing to do, but there's a point.  Boosted color saturation.  No attempt was made to do it well, just wanted to show you it's there.

 

Honestly, it's not the limited number of frames, it's processing.  Even with terrestrial experience, it takes time to learn astro processing.  What more total imaging time does for you is lower the noise, improve the all important signal to noise ratio.

 

Flats are perhaps _the_ most important calibration frames.  Not only do they correct vignetting and dust, they smooth out uneven pixel response.  Essential.  I always do bias and flats.  Don't do darks, have low thermal noise cameras.

 

The background on both M31 and M42 looks like the black point was raised too far.  People tend to do that when they don't shoot flats, to smooth the background out.  .

 

Here's how you get to a reasonable subexposure time (which depends on your skies).  Shoot a frame, look at the histogram on the back of your camera.  Do what it takes to get it about 1/3 over from the left.  Good enough.

 

You could probably benefit from this book, which discusses these issues and much more, in detail.

 

https://www.amazon.c...tography manual

 

attachicon.gifM31 add color Added.jpg

No, not at all! I am surprised to see that much of color layers could be popped by the PI. I did the adjustment in Lightroom. But can't really bring out that red color. Will definitely give PI a try. That's an expensive software though!

 

It's great to learn the importance of the flats. My previous understanding is that the flats only help to remove the dust dots. Thanks!

 

Yes, I use the histogram to check test shot before the sequence starts. Is 1/3 a little too much? My current checkpoint is at 1/5 to the left.

 

But, does increasing the number of light frames only helps on the noise reduction in stacking? Or does it help to SNR in the final stacking result? I ordered the book you recommended from Amazon. Thank again!



#17 mxcoppell

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Posted 29 November 2017 - 06:51 PM

Thanks.  The 240" subs may be a once or twice time thing.  I was lucky.  Balancing is key.  I use a Tripod Lens Mount Ring on my Canon lens.  This really helps getting the balance right.  I use 1 or 2 Star Adventurer counter weights on the DEC axis and spend the time to get the correct balance.  As for PA, its critical.  I level the tripod / mount and do an initial PA.  I then move the RA / DEC and orient the camera so the target is framed the way I want.  I then redo PA taking the time to get everything correct.  I then check to make sure the camera is still on target.  If necessary I readjust everything and redo PA.

 

Jim, how do you redo the PA once all the equipment are loaded on the mount? 

 

Every time for me to redo the PA, I need to loose the clutch knob so I could rotate the RA mounting platform to reset the initial position of the PA process as described in the user manual. But with all the payload mounted. It's not a joyful thing to do in the dark. Do you reset the initial PA position each time when redo the PA?



#18 mxcoppell

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Posted 29 November 2017 - 06:56 PM

Mine seems to behave better unguided, as guided..  undecided.gif

 

I have done 4 minutes subs unguided, and have nice round stars.. (200mm @ ap-c censor)

 

And last week I tried to guide the Star Adventurer with PHD2 + 50mm finder guider for the first time,

only 2 minutes subs due light pollution, but got slightly elongated stars...  bawling.gif  probably to much wind and user error...  wink.gif

 

Be sure to check the calibration of your polar scope before using, and to careful lock the RA-clamp after pointing your camera.

 

Maybe next time I'm gonna try the Polemaster with the Star Adventurer,

but i'm afraid locking the RA-clamp got a bad influence on precise polar alignment.

 

Plus.. with guiding/guidescope and polemaster and the need of a laptop,  it isn't a really portable set anymore..

 

p.s. nice picture Orion @ Fort Griffin. waytogo.gif

Thanks! For my case, it really bothers when seeing the guiding didn't improve the tracking performance. I will try again. 

4-minute @ 200mm without guiding! That's amazing!

 

 

As of Polemaster, I am not sure if it's easy to use with SA - SA is not a go-to mount, all the required RA/DEC rotating actions during Polemaster PA process will be manual rotating the knobs. If anybody could share the experience of using Polemaster with the SA, that will be great!



#19 bobzeq25

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Posted 29 November 2017 - 07:49 PM

 

Hope this doesn't come across as offensive, I'm just trying to help.

 

Downloaded your jpg, put it in Pixinsight.  Silly thing to do, but there's a point.  Boosted color saturation.  No attempt was made to do it well, just wanted to show you it's there.

 

Honestly, it's not the limited number of frames, it's processing.  Even with terrestrial experience, it takes time to learn astro processing.  What more total imaging time does for you is lower the noise, improve the all important signal to noise ratio.

 

Flats are perhaps _the_ most important calibration frames.  Not only do they correct vignetting and dust, they smooth out uneven pixel response.  Essential.  I always do bias and flats.  Don't do darks, have low thermal noise cameras.

 

The background on both M31 and M42 looks like the black point was raised too far.  People tend to do that when they don't shoot flats, to smooth the background out.  .

 

Here's how you get to a reasonable subexposure time (which depends on your skies).  Shoot a frame, look at the histogram on the back of your camera.  Do what it takes to get it about 1/3 over from the left.  Good enough.

 

You could probably benefit from this book, which discusses these issues and much more, in detail.

 

https://www.amazon.c...tography manual

 

attachicon.gifM31 add color Added.jpg

No, not at all! I am surprised to see that much of color layers could be popped by the PI. I did the adjustment in Lightroom. But can't really bring out that red color. Will definitely give PI a try. That's an expensive software though!

 

It's great to learn the importance of the flats. My previous understanding is that the flats only help to remove the dust dots. Thanks!

 

Yes, I use the histogram to check test shot before the sequence starts. Is 1/3 a little too much? My current checkpoint is at 1/5 to the left.

 

But, does increasing the number of light frames only helps on the noise reduction in stacking? Or does it help to SNR in the final stacking result? I ordered the book you recommended from Amazon. Thank again!

 

1/3 is OK, you wanted longer exposures, that's as far as I'd go.  1/5 can be good, too, it depends on the read noise of your camera.  Complicated.

 

PI's money cost is dirt cheap.  It's the cost in your time that's expensive, both learning it and using it.  Dwarfs the money cost.  I probably have a few hundred hours in.  Built a new computer for it, to avoid spending even more time with it.

 

I'm not sure what you mean about noise.  But I'm pretty nearly always talking about the final image, not some intermediate step.



#20 Jim Waters

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Posted 29 November 2017 - 09:29 PM

 

Thanks.  The 240" subs may be a once or twice time thing.  I was lucky.  Balancing is key.  I use a Tripod Lens Mount Ring on my Canon lens.  This really helps getting the balance right.  I use 1 or 2 Star Adventurer counter weights on the DEC axis and spend the time to get the correct balance.  As for PA, its critical.  I level the tripod / mount and do an initial PA.  I then move the RA / DEC and orient the camera so the target is framed the way I want.  I then redo PA taking the time to get everything correct.  I then check to make sure the camera is still on target.  If necessary I readjust everything and redo PA.

 

Jim, how do you redo the PA once all the equipment are loaded on the mount? 

 

Every time for me to redo the PA, I need to loose the clutch knob so I could rotate the RA mounting platform to reset the initial position of the PA process as described in the user manual. But with all the payload mounted. It's not a joyful thing to do in the dark. Do you reset the initial PA position each time when redo the PA?

 

Sorry, I should have gone into more detail.  Yes, if you rotate the RA axis the PS also rotates.  The PS doesn’t fit into the RA shaft like other mounts.  The PS shaft is actually the RA shaft.  There are 4 metric screws at the RA clutch end that join the two.  A mechanic friend made an extension bracket that attaches to the back of the Star Adventurer.  There are 4ea metric screws that hold the hour angle plate on the back of the Star Adventurer.  The extension mounts there.  It sticks out about 5” to one side of the Star Adventurer.  I have a secondary polar scope there that I can rotate.  I use an iOptron polar scope.  The reticle is the same basic concept but the magnification is a little greater.  This is the basic design of the AstroTrac.  It has its drawbacks but I can rotate the polar scope without having to untighten and retighten the RA clutch.  I have found that untightening  and retightening the RA clutch always throws off the polar alignment.  I sent Sky-Watcher USA a detailed e-mail pointing out the design limitations and problems above back in June ’17.  I also mentioned the poor polar scope illuminator design.  I got a Thank You reply.  I later talked to Tech-Support.

 

I have tried using a PoleMaster that I have mounted on the DEC arm but you need to rotate the RA axis +60 and back -60 degrees for the SW to align the mount.  I am working on a way to just rotate the PoleMaster on the DEC arm.



#21 mxcoppell

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Posted 08 December 2017 - 11:57 PM

@Jim Waters

 

Jim, got another question - I see many SA setups by mounting the camera collar directly to the DEC platform without a ball-head. Like the following:

Star%2520Adventurer%2520with%2520Equator

 

I didn't understand by this setup - once the PA is done, how to point the camera to the shooting target, if the target is not on the DEC plate. The RA axle could not be rotated anymore because it's RA-tracking. But removing the ball-head will definitely help the balance - do you have any experience to share?

 

Thanks!



#22 Jim Waters

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Posted 09 December 2017 - 01:34 AM

Not sure I understand the question.  PA can be done with the DEC Bracket as shown above.  There's a slot running almost the length of the bracket. 

To PA you unlock the RA Clutch and move the RA axis until the PS reticle's 3 and 9 positions are parallel or level to the ground.  Then you adjust the AZ and ALT and place Polaris in the correct position.  You then loosen the RA and DEC Clutches and position the camera on the target and lock the clutches back down.  If you use a 'strong' ball-head mounted on the DEC Bracket you don't need to move the RA / DEC Axis after you do PA.  Just move the camera.

 

You balance the setup by adjusting the weights on the DEC shaft.  Hopefully the lens on the camera isn't too long and heavy. 



#23 mxcoppell

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Posted 09 December 2017 - 09:44 AM

Jim, you got my question. 

 

I didn't realize that I could loose the RA and DEC clutches after PA - that's why I always put a ballhead on the DEC bracket. I think I will be afraid to do that with all the equipment mounted. Losing the RA clutch with force always messed up my PA. Need to practice. 

 

Now I realized that one more counter weight bar is required - ordered another one. 

 

Have a question about:

To PA you unlock the RA Clutch and move the RA axis until the PS reticle's 3 and 9 positions are parallel or level to the ground.

I used the 2nd method in the SA user manual to set the initial orientation of Polaris in Polar Scope (page 23) before start to put Polaris at the right position on the circle with iPhone PA App:

 

2. Then rotate the Date Graduation Circle to align Oct 31 to the 0 of the Time Graduation Circle and turn Eyepiece/Mounting Platform to align the Time Meridian Indicator to the 0 of the Time Meridian Circle (Fig 27). This is the date and time when the orientation of Polaris is directly below the north pole (6 o'clock).

By the above instruction, it should be the 2 and 8 positions are parallel or level to the ground correct? Or I did it wrong all the time? bow.gif



#24 mxcoppell

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Posted 15 December 2017 - 11:02 PM

Tried it again last night, still can't break 30s. 

 

- Now I am suspecting that if my PA process is correct (Can anybody share how to do initial PA and re-adjust PA after changing shooting target)?

- Balance is definite not there. Already purchased another counter weight to see if it improves. 

 

Here is a different style of Orion Nebula & Running Man - In the post more attention is put on popping out the nebula structure. Used a little cold color taste. 

 

20171213-orion-runningman.jpg

 

"Orion & Running Man", shot at Fort Griffin Historical Site

Sky-Watch Star Adventurer, D500(astro-modified)/70-200mm@200mm/TC1.4III

iso3200/f4/30s/60sub/25dark/25bias


Edited by mxcoppell, 15 December 2017 - 11:09 PM.

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#25 mxcoppell

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Posted 17 December 2017 - 12:02 AM

My first B33 attempt from the Meteor Shower night last week.

 

mx-20171213-horsehead-nebula.jpg

 

"My First Horsehead Nebula", shot at Fort Griffin Historical Site
Sky-Watch Star Adventurer, D500(astro-modified)/70-200mm@200mm/TC1.4III
iso5000/f4/30s/120sub/25dark/25bias


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