Working on improving my guiding.... Open PHD Guiding project PHD2 · Christian Bennich · ... · 46 · 979 · 6

Bennich 2.11
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I am making good improvements, and have gotten my bigger rig to guide much better. Now trending towards getting below 0,7".
One question though. 
When I am using PHD2's Guiding Assistant - my RA seems to just trend in one direction. 

Any ideas to what might be causing this, is it expected or?
I am still trying to get the "Black Voodoo" feeling of Autoguiding to go away from my mind 

Screenshot 2024-05-05 at 02.02.29.png
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IrishAstro4484 5.96
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Just off the top of my head.... You don't have a cable snagging by any chance?
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messierman3000 4.02
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oh, yeah

make sure no cables are snagging on the top of your head





can cables be that messy? silly joke that came off the top of my head...
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Rustyd100 4.26
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Another basic thing to check: Make sure the guide scope calibration is set to the correct side of the meridian.
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Alexn 0.00
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RA trending off in one direction indicates a RA tracking issue. Is your mount tracking in sidereal rate? 

Cable drag/snag will do it too, as will a gross imbalance in RA. 

Overall, your guiding assistant results look pretty reasonable... I know that optimisation is a good thing, but sometimes you're trying to fix what isn't broken. Your total rms is far below 0.5"..
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WhooptieDo 9.24
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It should come back.   That's likely just your periodic error.   You need to run it for roughly 480 seconds for a full worm cycle.

I don't see anything wrong other than it indicating your polar alignment is way off.
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cosmetatos 0.90
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I don't see anything wrong other than it indicating your polar alignment is way off.

Wouldn't bad polar alignment impact DEC drifting too?
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Bennich 2.11
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Hi all

Thank you for your input!

The funny thing is, when guiding it’s really really good. 
During last night I switched my RA to the PPEC, which put me between 0,7” and 0,6” when guiding which I believe is ok for my equipment. 

Prior to the session, I polar aligned first visually, then with NINA 3-point polar alignment. It was below 30”, so I assume the alignment would be ok. 
I realise that there can be measurement differences from tool to tool. 

What I saw on other “Guide Assistant” runs was that, as time progressed the Polar Alignment Error would drop towards 1’ or less. 

All cables are well connected, controlled and there are no snagging as far as I can see when looking at the mount when this happen. Also I have balanced the mount and double checked that it is not completely crazy 😁
So I believe these 2 are sort of ok as well - will check again at next Clear Skies opp. 

I did one long “Guide Assist” +10minutes, that seemed to behave similar to above. 

I am tracking at Sideareal rate, but it’s worth checking if the guiding is set on the wrong side of the meridian s suggested by @Dave Rust

Will go over everything once I have clear skies again one of the coming days.
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Starman609 6.45
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Check these settings:

1  in PHD2, increase the calibration steps under Advanced Settings/Guiding to 2200
2  in the ASCOM box, make sure the Sidereal box is checked, it will automatically switch to Custom after doing a PPEC that may cause the RA to skew up

When calibrating, make sure you are on the East side of the meridian and at about 30-45 degrees near the meridian for best results.
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Jbis29 1.20
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Eddie Bagwell:
Check these settings:

1  in PHD2, increase the calibration steps under Advanced Settings/Guiding to 2200
2  in the ASCOM box, make sure the Sidereal box is checked, it will automatically switch to Custom after doing a PPEC that may cause the RA to skew up

When calibrating, make sure you are on the East side of the meridian and at about 30-45 degrees near the meridian for best results.

Out of curiosity, what is the benefit of #1?
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Starman609 6.45
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Joseph Biscoe IV:
Eddie Bagwell:
Check these settings:

1  in PHD2, increase the calibration steps under Advanced Settings/Guiding to 2200
2  in the ASCOM box, make sure the Sidereal box is checked, it will automatically switch to Custom after doing a PPEC that may cause the RA to skew up

When calibrating, make sure you are on the East side of the meridian and at about 30-45 degrees near the meridian for best results.

Out of curiosity, what is the benefit of #1?

During PHD2 calibration, the mount would not skew north and seemed to be stuck and failed calibration. After increasing the calibration steps, the mount was able to skew north and successfully complete the task. I have the EQ6R and not sure if that is only associated to this mount, but it did solve the problem. This isn't the actual number of steps in calibration but rather the pulse force sent to the mount to get it to move.
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WhooptieDo 9.24
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Cosmetatos:
I don't see anything wrong other than it indicating your polar alignment is way off.

Wouldn't bad polar alignment impact DEC drifting too?



Yes, and it shows drift in his short screenshot.  PHD2 is pretty good at measuring this stuff.  If it says it's 3.8 arc min, its probably accurate.  

Christian, just a couple tips for you.   Dump NINA TPPA.  It sucks.  You can run it 3 times and get 3 different results.   Pay the 10 bucks for Sharpcap and use it's polar alignment feature.  It's much quicker and far more accurate.    I recently made the switch and it's night and day difference.  My PA is almost dead on.  

Also, try faster updates for your EQ6.   I typically run 1.5 seconds, but sometimes 1 second depending on mount performance.  The faster updates ensures it can correct faster.   2 seconds and more have always yielded poor results for me.   Also, remember seeing exists, and you could just be at the performance limit for that night.  

As for the person that recommended changing guide steps.... I'd recommend not.   Leave it at whatever PHD calculated for you.  That number is based on your sampling and I'd imagine you'd get adverse results changing it.
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WhooptieDo 9.24
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Eddie Bagwell:
Joseph Biscoe IV:
Eddie Bagwell:
Check these settings:

1  in PHD2, increase the calibration steps under Advanced Settings/Guiding to 2200
2  in the ASCOM box, make sure the Sidereal box is checked, it will automatically switch to Custom after doing a PPEC that may cause the RA to skew up

When calibrating, make sure you are on the East side of the meridian and at about 30-45 degrees near the meridian for best results.

Out of curiosity, what is the benefit of #1?

During PHD2 calibration, the mount would not skew north and seemed to be stuck and failed calibration. After increasing the calibration steps, the mount was able to skew north and successfully complete the task. I have the EQ6R and not sure if that is only associated to this mount, but it did solve the problem. This isn't the actual number of steps in calibration but rather the force sent to the mount to get it to move.


Sounds to me like your guide rate is possibly too low, or you have a balance/snag issue.  Option 3 is large backlash.
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HegAstro 11.99
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Brian Puhl:
Dump NINA TPPA.  It sucks.  You can run it 3 times and get 3 different results


Completely opposite to my experience. 3PPA has been nothing but reliable. I have used it for well over a year now and repeat measurements always show that the alignment is accurate. Verified by PHD2 and guiding results too.
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Starman609 6.45
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Brian Puhl:
Sounds to me like your guide rate is possibly too low, or you have a balance/snag issue.  Option 3 is large backlash.

Could be the guide rate too low, I changed it to .8 and PHD2 keeps automatically changing it back to .5. There are no balance or snag issues, and backlash seems to be minimal but there.

I had a difficult time setting up PHD2 a couple of years ago but after getting all of the settings ironed out, I haven't had any problems with guiding since.
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WhooptieDo 9.24
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Arun H:
Brian Puhl:
Dump NINA TPPA.  It sucks.  You can run it 3 times and get 3 different results


Completely opposite to my experience. 3PPA has been nothing but reliable. I have used it for well over a year now and repeat measurements always show that the alignment is accurate. Verified by PHD2 and guiding results too.



Definitely strange.  My sentiments are echoed by alot of my astro friends, they're actually the ones that convinced me to switch.    I could do TPPA on NINA and literally just sit there, without touching anything and watch the calculations drift.   Never made any sense.  

Sharpcap was perfect the first time every time so far.
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WhooptieDo 9.24
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Eddie Bagwell:
Brian Puhl:
Sounds to me like your guide rate is possibly too low, or you have a balance/snag issue.  Option 3 is large backlash.

Could be the guide rate too low, I changed it to .8 and PHD2 keeps automatically changing it back to .5. There are no balance or snag issues, and backlash seems to be minimal but there.

I had a difficult time setting up PHD2 a couple of years ago but after getting all of the settings ironed out, I haven't had any problems with guiding since.



Any backlash in RA is kinda bad.  You can get away with it in dec kinda.   I use 0.5 guide rate as well, so that sounds fine.
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Bennich 2.11
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Brian Puhl:
Cosmetatos:
I don't see anything wrong other than it indicating your polar alignment is way off.

Wouldn't bad polar alignment impact DEC drifting too?



Yes, and it shows drift in his short screenshot.  PHD2 is pretty good at measuring this stuff.  If it says it's 3.8 arc min, its probably accurate.  

Christian, just a couple tips for you.   Dump NINA TPPA.  It sucks.  You can run it 3 times and get 3 different results.   Pay the 10 bucks for Sharpcap and use it's polar alignment feature.  It's much quicker and far more accurate.    I recently made the switch and it's night and day difference.  My PA is almost dead on.  

Also, try faster updates for your EQ6.   I typically run 1.5 seconds, but sometimes 1 second depending on mount performance.  The faster updates ensures it can correct faster.   2 seconds and more have always yielded poor results for me.   Also, remember seeing exists, and you could just be at the performance limit for that night.  

As for the person that recommended changing guide steps.... I'd recommend not.   Leave it at whatever PHD calculated for you.  That number is based on your sampling and I'd imagine you'd get adverse results changing it.

@Brian Puhl 😁😁, I do already have SharpCap. Will give the PA feature a go. 
As with anything Astro I have seen different opinions on whether NINA or SharpCap is more precise when it comes to PA. 
Will try it!!
Thx
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HegAstro 11.99
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Brian Puhl:
Definitely strange.  My sentiments are echoed by alot of my astro friends, they're actually the ones that convinced me to switch.    I could do TPPA on NINA and literally just sit there, without touching anything and watch the calculations drift.   Never made any sense.


I suspect it may depend on how close to the pole you actually are. What I will say is that if you are a bit farther away and to the TPPA, you can be off. What I have learned to do is, if the initial alignment is more than a degree off, do the alignment, and then repeat TPPA. This gets me dead on. Sharpcap also, I believe, requires you to be within a few degrees of the pole, as I remember.
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bluemoon737 3.61
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What kind of scope? If moving mirror (SCT) and if guide assistant was done at or near the meridian, then it could just be the mirror shifting as you are passing through the meridian.
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TiffsAndAstro 0.00
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Christian Bennich:
Brian Puhl:
Cosmetatos:
I don't see anything wrong other than it indicating your polar alignment is way off.

Wouldn't bad polar alignment impact DEC drifting too?



Yes, and it shows drift in his short screenshot.  PHD2 is pretty good at measuring this stuff.  If it says it's 3.8 arc min, its probably accurate.  

Christian, just a couple tips for you.   Dump NINA TPPA.  It sucks.  You can run it 3 times and get 3 different results.   Pay the 10 bucks for Sharpcap and use it's polar alignment feature.  It's much quicker and far more accurate.    I recently made the switch and it's night and day difference.  My PA is almost dead on.  

Also, try faster updates for your EQ6.   I typically run 1.5 seconds, but sometimes 1 second depending on mount performance.  The faster updates ensures it can correct faster.   2 seconds and more have always yielded poor results for me.   Also, remember seeing exists, and you could just be at the performance limit for that night.  

As for the person that recommended changing guide steps.... I'd recommend not.   Leave it at whatever PHD calculated for you.  That number is based on your sampling and I'd imagine you'd get adverse results changing it.

@Brian Puhl 😁😁, I do already have SharpCap. Will give the PA feature a go. 
As with anything Astro I have seen different opinions on whether NINA or SharpCap is more precise when it comes to PA. 
Will try it!!
Thx


would be interesting to read what you find.
Cuiv video seemed to suggest they were both about the same?
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Bennich 2.11
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·  1 like
TiffsAndAstro:
Christian Bennich:
Brian Puhl:
Cosmetatos:
I don't see anything wrong other than it indicating your polar alignment is way off.

Wouldn't bad polar alignment impact DEC drifting too?



Yes, and it shows drift in his short screenshot.  PHD2 is pretty good at measuring this stuff.  If it says it's 3.8 arc min, its probably accurate.  

Christian, just a couple tips for you.   Dump NINA TPPA.  It sucks.  You can run it 3 times and get 3 different results.   Pay the 10 bucks for Sharpcap and use it's polar alignment feature.  It's much quicker and far more accurate.    I recently made the switch and it's night and day difference.  My PA is almost dead on.  

Also, try faster updates for your EQ6.   I typically run 1.5 seconds, but sometimes 1 second depending on mount performance.  The faster updates ensures it can correct faster.   2 seconds and more have always yielded poor results for me.   Also, remember seeing exists, and you could just be at the performance limit for that night.  

As for the person that recommended changing guide steps.... I'd recommend not.   Leave it at whatever PHD calculated for you.  That number is based on your sampling and I'd imagine you'd get adverse results changing it.

@Brian Puhl 😁😁, I do already have SharpCap. Will give the PA feature a go. 
As with anything Astro I have seen different opinions on whether NINA or SharpCap is more precise when it comes to PA. 
Will try it!!
Thx


would be interesting to read what you find.
Cuiv video seemed to suggest they were both about the same?

Yeah, I have seen that video as well 😜

Will post my findings as soon as the skies clear out, later this week.
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WhooptieDo 9.24
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·  1 like
Christian Bennich:
TiffsAndAstro:
Christian Bennich:
Brian Puhl:
Cosmetatos:
I don't see anything wrong other than it indicating your polar alignment is way off.

Wouldn't bad polar alignment impact DEC drifting too?



Yes, and it shows drift in his short screenshot.  PHD2 is pretty good at measuring this stuff.  If it says it's 3.8 arc min, its probably accurate.  

Christian, just a couple tips for you.   Dump NINA TPPA.  It sucks.  You can run it 3 times and get 3 different results.   Pay the 10 bucks for Sharpcap and use it's polar alignment feature.  It's much quicker and far more accurate.    I recently made the switch and it's night and day difference.  My PA is almost dead on.  

Also, try faster updates for your EQ6.   I typically run 1.5 seconds, but sometimes 1 second depending on mount performance.  The faster updates ensures it can correct faster.   2 seconds and more have always yielded poor results for me.   Also, remember seeing exists, and you could just be at the performance limit for that night.  

As for the person that recommended changing guide steps.... I'd recommend not.   Leave it at whatever PHD calculated for you.  That number is based on your sampling and I'd imagine you'd get adverse results changing it.

@Brian Puhl 😁😁, I do already have SharpCap. Will give the PA feature a go. 
As with anything Astro I have seen different opinions on whether NINA or SharpCap is more precise when it comes to PA. 
Will try it!!
Thx


would be interesting to read what you find.
Cuiv video seemed to suggest they were both about the same?

Yeah, I have seen that video as well 😜

Will post my findings as soon as the skies clear out, later this week.



Easiest way in my opinion, do an alignment both ways and measure drift with guiding assistant afterwards.   It'll be quite obvious.

Hell, maybe I'll make a video about this. Lol
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WhooptieDo 9.24
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Arun H:
Brian Puhl:
Definitely strange.  My sentiments are echoed by alot of my astro friends, they're actually the ones that convinced me to switch.    I could do TPPA on NINA and literally just sit there, without touching anything and watch the calculations drift.   Never made any sense.


I suspect it may depend on how close to the pole you actually are. What I will say is that if you are a bit farther away and to the TPPA, you can be off. What I have learned to do is, if the initial alignment is more than a degree off, do the alignment, and then repeat TPPA. This gets me dead on. Sharpcap also, I believe, requires you to be within a few degrees of the pole, as I remember.



Sharpcap definitely wants you to be close.  The initial plate solve gives you a green circle.  If it's not there, then you need to get closer initially.  Hopefully folks can get close on their own lol. 

TPPA on the other hand has literally sent me in circles many times.   I'll do one alignment... Then remeasure, and it will say I'm 2 arc min off.   Follow the corrections, then remeasure and I'll be 2 arc min in the opposite direction.   It was driving me insane.  Once I got it dialed in, I'd literally watch the numbers drift off by 1 arc second per second.   Never stops.  Something was really off about how it calculates.
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Bennich 2.11
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So, I gave SC Polaralignment a go and the routine seems really nice and easy. 
This is the result: 
Screenshot 2024-05-08 at 23.17.38.png
I then ran my Autoguide Calibration for 1000 seconds, which looked like this: 
Screenshot 2024-05-08 at 23.53.05.pngScreenshot 2024-05-08 at 23.53.20.png

I will now go and see what N.I.N.A. says in terms of my precision on PA now!

Be right back 
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