Polaris moves in polar scope depending on

[900SL]

Thus is getting hilarious. 

[StevieDvd]

7 minutes ago, 900SL said:

Thus is getting hilarious. 

It took me a while for the penny to drop that there was an option that had a polar scope and a flat 3/8" tripod like the SW Star Adventurer GTi 😀

[TiffsAndAstro]

58 minutes ago, StevieDvd said:

Then how are you adjusting the mount in azimuth?????

I see from your other posts you have mentioned a SW Gti is it this one

That has the azimuth pin in the base of the mount so you can't see it and it allows the use of a 3/8 tripod.

I'm bit shocked I've never noticed it. I believe you but still gonna check asap.

i just looked and the base of the mount has only a female 3/8inch hole. nothing else.

Edited March 5 by TiffsAndAstro

[TiffsAndAstro]

26 minutes ago, 900SL said:

Thus is getting hilarious. 

I'm happy its entertaining, but also sorry I'm struggling so much and taking advantage of members generous time and effort. It's probably something that could be sorted in 5 mins in person

[TiffsAndAstro]

just to clarify.

once i've centered polaris in the polar scope cross hair and then used alt bolt to position in at the top in the center circular line - do i rotated RA to move polaris into the correct position, or do i use the alt/az bolts?

[StevieDvd]

21 minutes ago, TiffsAndAstro said:

just to clarify.

once i've centered polaris in the polar scope cross hair and then used alt bolt to position in at the top in the center circular line - do i rotated RA to move polaris into the correct position, or do i use the alt/az bolts?

Keep using the alt/az bolts.

Polaris will be in a certain position at a given time.  So if it's due to be at the eleven o'clock position that's where you should see it in the circle when you are aligned.

If you imagine the circle is like a circular train track, then at any given time Polaris (the train) should be in a set part of the track.  If you are correctly PA'd then turning your mount in RA 360 degrees, Polaris will stay in place and the track spins around it. If it goes off track then your mount pivot point is not correct in relation to Polaris.

Remember that you are trying to adjust the central pivot point of your mount to that of the NCP. We can do that by noting the position of Polaris at a set time/date and from that can work out where your mount pivot point should be.

Given your statement about age and back issues then I'd suggest doing a basic PA in the polar scope (align in the middle of the cross). Then use software PA (like Synscan, Sharpcap, NINA etc) to get it better. 

And don't worry about the questions some of us are retired and don't mind the challenge of getting someone new on the right track.  Personally I think Polar scopes are evil and designed to sell back ache remedies. I have not used one for years.😀

 

[TiffsAndAstro]

14 minutes ago, StevieDvd said:

Keep using the alt/az bolts.

Polaris will be in a certain position at a given time.  So if it's due to be at the eleven o'clock position that's where you should see it in the circle when you are aligned.

If you imagine the circle is like a circular train track, then at any given time Polaris (the train) should be in a set part of the track.  If you are correctly PA'd then turning your mount in RA 360 degrees, Polaris will stay in place and the track spins around it. If it goes off track then your mount pivot point is not correct in relation to Polaris.

Remember that you are trying to adjust the central pivot point of your mount to that of the NCP. We can do that by noting the position of Polaris at a set time/date and from that can work out where your mount pivot point should be.

Given your statement about age and back issues then I'd suggest doing a basic PA in the polar scope (align in the middle of the cross). Then use software PA (like Synscan, Sharpcap, NINA etc) to get it better. 

And don't worry about the questions some of us are retired and don't mind the challenge of getting someone new on the right track.  Personally I think Polar scopes are evil and designed to sell back ache remedies. I have not used one for years.😀

 

Ty for all this. Hopefully I can give it a go tonight.

Edited March 5 by TiffsAndAstro

[TiffsAndAstro]

2 hours ago, StevieDvd said:

Keep using the alt/az bolts.

Polaris will be in a certain position at a given time.  So if it's due to be at the eleven o'clock position that's where you should see it in the circle when you are aligned.

If you imagine the circle is like a circular train track, then at any given time Polaris (the train) should be in a set part of the track.  If you are correctly PA'd then turning your mount in RA 360 degrees, Polaris will stay in place and the track spins around it. If it goes off track then your mount pivot point is not correct in relation to Polaris.

Remember that you are trying to adjust the central pivot point of your mount to that of the NCP. We can do that by noting the position of Polaris at a set time/date and from that can work out where your mount pivot point should be.

Given your statement about age and back issues then I'd suggest doing a basic PA in the polar scope (align in the middle of the cross). Then use software PA (like Synscan, Sharpcap, NINA etc) to get it better. 

And don't worry about the questions some of us are retired and don't mind the challenge of getting someone new on the right track.  Personally I think Polar scopes are evil and designed to sell back ache remedies. I have not used one for years.😀

 

ok so an update: its disastrously bad.  11 second sub biggest streaks ive seen. so i hibernated, cleared settings re polar aligned via polar  scope and another star alignment didn't do a polar in app and the result is slightly less streaking but not much. see attachment.

i have no idea where to go from here.

my mel max from after taking attachment:

mel 14.4' maz -5'57.2' tilt 3'32.7'

id get better results pointing my camera on a ball head and tripod.

gonna attempt a pa via synscap again can't be any worse.

***********************

ok didn't use synscap to polar align, purely polar scope and alt/ax then a 2 star alignment and its even worse trails.  its like tracking isn't even on, but the app says it is.

my mel maz is exactly same as above btw if that points to anything.

IMG_8488.CR2

Edited March 5 by TiffsAndAstro

[TiffsAndAstro]

one final update for now ty anyone who was reading

did another polar alignment via scope, did another two star alignmnent. did a focus test on jupiter looks ok and did a 60 sec sub and the star trailing was within the error of how bad my star shapes are.

i have stopped down to 4 or 5.6 (can't check with lens heater on and don't want to disturb it) btw

so i went back to orion and did a 60 sec test sub there and it seems ok too. 

so to sum up i have no idea what i did so badly and i have no idea what i did to fix it. Im full of confidence and optimism

my mel maz is still as posted above btw.

gonna let it run at 60 sec subs until orion drops too low and will stack and process see what people think.

Edited March 5 by TiffsAndAstro

[alacant]

5 hours ago, TiffsAndAstro said:

It's probably something that could be sorted in 5 mins in person

Hi

Some stuff is difficult or impossible to describe in words on a forum.

The in person person is at your local astro club. Any of the members would be only too willing to get you polar aligned and imaging. Probably in less than 5 minutes!

Cheers 

[Elp]

As mentioned in your other thread "bird shapes", you just need to polar align an EQ mount. You do not touch the mount again after it's polar aligned. I don't know why you're trying to do a two star alignment after polar alignment. The mount knows the star model based on its latitude and longitude location settings which have to be correct to where you are in the world. Maybe I'm wrong, but I've only ever done a 1/2/3 star alignment with my azgti in alt az mode. All my eq mounts are polar aligned only.

[TiffsAndAstro]

51 minutes ago, alacant said:

Hi

Some stuff is difficult or impossible to describe in words on a forum.

The in person person is at your local astro club. Any of the members would be only too willing to get you polar aligned and imaging. Probably in less than 5 minutes!

Cheers 

yeah i made inquiries a few weeks back, expecting trouble i just haven't been able to get to one of their meetings yet

[TiffsAndAstro]

37 minutes ago, Elp said:

As mentioned in your other thread "bird shapes", you just need to polar align an EQ mount. You do not touch the mount again after it's polar aligned. I don't know why you're trying to do a two star alignment after polar alignment. The mount knows the star model based on its latitude and longitude location settings which have to be correct to where you are in the world. Maybe I'm wrong, but I've only ever done a 1/2/3 star alignment with my azgti in alt az mode. All my eq mounts are polar aligned only.

well i just did a regular pa via the scope then a two star alignment in the app and NO polar alignment in app via alt/az bolts. seem to  be back to doing decent 60 sec subs now. read below for more

also, i did more stopping down tests and dropped it from wide open f2.8 to either f4 or f5.6, after checking a few tests - and particularly jupiter and its moons (which is v handy) i quite liked the results. ovalish, but from the little screen, i think the best i've managed. i will post my results of orion when i can for more  hilarity, 

its the least i can do for all the help i've received

Edited March 5 by TiffsAndAstro

[TiffsAndAstro]

so the reason why that sub i linked looks so bad as if tracking wasn't on is because.......its possible tracking wasn't on.

even though i checked. I think the app on my older version of android sometimes crashes/hangs or causes the app to set itself back to not tracking. restarting and reconnecting the app to the mount and setting tracking back on seemed to do the trick.

not very reassuring though. gonna see if i can run the app on something else.

[bosun21]

How are you adjusting the azimuth movement during polar alignment if your tripod doesn't have a north pin fitted?

[TiffsAndAstro]

2 hours ago, bosun21 said:

How are you adjusting the azimuth movement during polar alignment if your tripod doesn't have a north pin fitted?

the small green bolts on either side of the mount near the base.

[bosun21]

9 hours ago, TiffsAndAstro said:

the small green bolts on either side of the mount near the base.

If your tripod doesn't have a pin fitted then those screws wont move anything.

[StevieDvd]

Just now, bosun21 said:

If your tripod doesn't have a pin fitted then those screws wont move anything.

He has a SW GTi mount that has a 3/8 base that has a built in adjustment system. The green bolts push against a built in inverted stop and turns the top of the mount. 

[bosun21]

17 minutes ago, StevieDvd said:

He has a SW GTi mount that has a 3/8 base that has a built in adjustment system. The green bolts push against a built in inverted stop and turns the top of the mount. 

So you mean there's a pin protruding out the bottom of the mount head that fits into the hole on the top of the tripod? 

[StevieDvd]

13 hours ago, TiffsAndAstro said:

one final update for now ty anyone who was reading

did another polar alignment via scope, did another two star alignmnent. did a focus test on jupiter looks ok and did a 60 sec sub and the star trailing was within the error of how bad my star shapes are.

i have stopped down to 4 or 5.6 (can't check with lens heater on and don't want to disturb it) btw

so i went back to orion and did a 60 sec test sub there and it seems ok too. 

so to sum up i have no idea what i did so badly and i have no idea what i did to fix it. Im full of confidence and optimism

my mel maz is still as posted above btw.

gonna let it run at 60 sec subs until orion drops too low and will stack and process see what people think.

Your mel/maz settings still be the same is worrying.  It is the adjustment that the mount expects to correct your PA when doing a goto.  

The SW PA/Align process for users without a polarscope is documented in the handset manual and involves doing a series of PA and Aligns to reduce the Mel/Maz 

Even the slightest adjustment  of the Alt/Az would change those numbers. But if the app is the same as the handset method the values may only change after last 2 or 3 star alignment

[StevieDvd]

Just now, bosun21 said:

So you mean there's a pin protruding out the bottom of the mount head that fits into the hole on the top of the tripod? 

No it's all enclosed. The pin is in the upper part and the adjustments bolts are in the part which connects to the tripod. The inverse of the wedges used to put an AZGTi  in eq mode (they can't have azimuth pins in the tripod either). Suffice to say the missing azimuth pin was a red herring which has taken the thread off course.

 

[bosun21]

1 minute ago, StevieDvd said:

No it's all enclosed. The pin is in the upper part and the adjustments bolts are in the part which connects to the tripod. The inverse of the wedges used to put an AZGTi  in eq mode (they can't have azimuth pins in the tripod either). Suffice to say the missing azimuth pin was a red herring which has taken the thread off course.

 

Got it 👍.

[malc-c]

I did say it was a simplified set up, and I've never seen an Gti scope to find out that skywatcher changed the traditional design of having a pin on the mount onto which the azimuth adjustment screws press against.

Given that this thread is now some three pages long and we seem to have covered basic polar alignment which has only led to confusion, I agree with the poster above that it would be worth making further enquiries at your local club or society.  We have members in our society who are often willing to assist on a private one to one basis where its easier to teach people how to set a scope up by being there than over the phone or posts on a forum.  As a society we also run telescope workshops where members / or prospective members can bring their scopes along and get answers to questions they may have.

With regards to the requirement of rotating the mount to place polaris in the correct position, hopefully the drawing below might help.

 

For argument and to make it simple, lets say that Polaris is at the 9 O'clock position in its 24 hour rotation around the NCP.  Placing Polaris on the ring at the 9 O'clock would correctly place the NCP to the right.   If you didn't know the position of Polaris and simply placed it anywhere on that ring, such as at the 3 O'clock position the this would place the NCP (and the RA axis of the mount) way off to the left.

I also read through the online manual and the mount set up, particularly the PA is very poorly defined.  Goes off at a tangent to describe a utility to show the Polaris Hour, but then no real detail on what to do with it.

One other thing, I think the OP needs to take on board that PA is critical if you are doing unguided exposures.  The earth is spinning really fast and any error will result in anything form egg shaped stars to trails.  I can remember a thread where people were competing for the longest un-guided exposure before misshapen  stars or trails were seen when using an HEQ5 mount.  From memory it was around 5 minutes but the mount had been hypertuned and PA was done via plate solving, but that was the extreme required.   Given the large tolerances and variables such as the way Polaris appears to move within the polar scope 20 - 30 seconds exposures will probably show trailing etc when un-guided.

 

 

[StevieDvd]

Okay it appears you have grasped the PA process both using the polarscope and the app.  And as you can get the mel/maz values can see how far off you are from a good PA, at best these would both be zero. But probably 1 arc-minute would be the best you could expect to get (according to SW) 

I had the SW GTi briefly before I upgraded to a ZWO AM5 and never used the polarscope. I set the Alt based on my location and pointed North using my iPhone then PA'd via the app or a connected ASIAir, that was for visual I did not image with the SW Gti.

So based on your equipment and software:

As I still have the Syncan app and can set it to simulate mode I can see the stages you would go through as an iterative process (align, PA, align & check)

• Check your date/time & location are correct in the app
• Start PA process until mel/maz value is as low as possible
• Do a 2 or 3 star alignment
  • End with an Up/Right click
  •  Check the mel/maz error
• Do the PA using the Alt/Az bolts as needed.
• Redo a 2 or 3 star alignment
  • End with an Up/Right click
  •  Check the mel/maz error
• Repeat  as required

When you adjust the Azimuth bolts, loosen one side as you tighten the other, but make sure they are not left loose. The end on Up/Right move for aligning is per SW notes to cater for backlash.

Home position - if your PA is good a poor home position may make the first go-to look bad.  I would loosen the clutches and centre the object - not use the cursor keys or alt/az bolts.  I'd then do a go to 'home' and retry the first go to - the mount will set a home position, better than you can, and later each subsequent go to should be accurate as well.

 

NB You can add a custom target in the app for 'home' to be able to do a go to home

     

 

Hope this helps rather than confuse. I think I have covered the essentials - someone may spot anything I've missed.

Steve

 

 

[TiffsAndAstro]

10 hours ago, bosun21 said:

If your tripod doesn't have a pin fitted then those screws wont move anything.

well polaris moves when i use them