TSX: "Accurate Polar Alignment" feature

[PRejto]

Last night I tried this new feature in TSX that takes info from the polar alignment report of T-Point, has one slew to a low point to the N or S. It then offsets the mount from a "fiducial" star. You then physically move the mount to recenter this star. The polar alignment is then complete and it not necessary to recalibrate into the model (per previous older methods) as the model is automatically updated to the new position upon completion.

Great, but not working (for me and one other person I know who tried it). e.g., the PA report indicates that the mount should be lowered 2 tics but doing so makes the star move further away from the center.

I suspect it may be a S.H. bug. Has anyone else experienced this or had success? I don't believe that moving the mount contrary to the PA report can be the answer. One would need to conclude that the PA report is totally wrong. As we have used the PA report for years to achieve good PA (with recalibration verification that adjustments to the mount are valid) it seems unlikely that now the PA report is corrupted.

Peter

[SimmoW]

Sounds like a good new feature. What page of the manual is it on or is it such a new feature that it's undocumented? Thks

[PRejto]

I'm not sure! But the usage is self explanatory.

Today this was posted at Software Bisque:

Re: Issue With Accurate Polar Alignment (http://www.bisque.com/sc/forums/p/25105/118398.aspx#118398)
By PWallace in TheSkyX Professional Edition

https://ci4.googleusercontent.com/proxy/WBF37hhk6J7FVA1_iIOh6p6qqFMlGYvuscD PNX_0v3OzbNRx1AQOCSrjkmNe3soFBTDfqj trzlTdzi2zKXQg--C-j06OKJzW5of8-AucIYp25w=s0-d-e1-ft#http://www.bisque.com/sc/Themes/hawaii/images/icon-quote.gif Peter:
Is this a Southern Hemisphere bug possibly?
You've jogged my memory. See www.bisque.com/sc/forums/p/24730/115868.aspx#115868 (http://www.bisque.com/sc/forums/p/24730/115868.aspx#115868) Matthew Bisque said this at the time (May 27):
"This southern hemisphere only bug, introduced in daily build 8805 has been corrected in TheSky build 8916 or later (to be released as a daily build soon).
As a work around, in the meantime, rely on the details given near the end of the report."

Build 8908 latest version so this has yet to be fixed!

Peter

[frolinmod]

Let's all beat up on Daniel Bisque and convince him to publicly release a new daily build sooner rather than later. LOL if they were actually released to the public daily.

[PRejto]

Well, that's a bit harsh! But I agree that sooner rather than later with a known bug would be rather helpful. For sure it would have saved me a couple of days of confusion. They have know about this since May and now it's July.

It appears that to see accurate information about T-Point PA one must click on "Show alternative PA" at the bottom of the report. Sure enough the information about ME is reversed (and correct). So that "probably" means that the offset calculated by "Accurate PA" is correct as far as ME. My results with MA seem odd. My report said to move the mount 10 tics but the photo I took showed that the offset was quite small in that direction (towards the y axis). My camera is North up so ME is the vertical axis, MA horizontal.

Peter

[DavidTrap]

Well, it would be nice if they would reply to queries... I've politely asked for assistance and told them I'm willing to spend significant amounts of money, yet their communication is sporadic at best! Hardly confidence inspiring when a new mount is $10-25k

DT

[gregbradley]

Nice detective work there Peter. Yes I thought it was odd when T-Point said no adjustment needed (and then it has lower by 1.3tics which is miniscule) but when I used accurate polar alignment the adjustments were in the opposite direction and quite large.

Hmm. Need to do another large T-point model and follow TPoint directions only.

Greg.

[PRejto]

Actually Greg, be careful how you read this! I put up another post at SB that Patrick Wallace answered.

1. The report that you normally look at is incorrect in ME and says to move the mount in the wrong direction.
2. If you go to the bottom of that page there is a check box for advanced PA settings. The information in that section is correct!
3. Accurate PA feature uses information from the advanced PA settings.
4. So, when you just ignored what #1 said and you just re-centered the star you actually did exactly the right thing! Your PA should be right on.

This seems to me to be quite poor on the part of SB. They have known about this bug in the S.H. for nearly 6 weeks but have not fixed up the report that all of us depend on. If I were setting up nightly in the field having the wrong info displayed this would probably stuff up lots of hours if not the whole night. I really think it has been a big mistake for them to wait this long to fix something that is probably quite easy to fix. Maybe we just don't count very much down here in the S.H. Admittedly the number of SB mounts in the S.H. is probably small comparatively. However, it is a serious community and I think deserves better.

Peter

[gregbradley]

OK so I do use the accurate PA recentre the star low in the north or south. That's what I did last time and autoguiding errors went down so I figured it was correct. It did throw me a bit like you said as I had to adjust in the opposite direction and by quite a lot more than the report said.

Why does the TPoint polar alignment report suddenly generate wrong adjustments? Gee is that for all its adjustments? As I did several iterations to get to that last one with the accurate PA.

In their defence SB does warn that the latest build may have bugs.

Greg.

[gregbradley]

For that sort of money David I would seriously consider the AP1600 with absolute encoders. That sounds state of the art and under .2 arc sec guiding. Unguided 10 minute round star images are possible. Plus you can install them later as an upgrade at home. ME11 needs to go back to Bisque for that and ME11 is more expensive than AP1600 in the first place.

I have nothing but glowing recommendations for anything I have had from AP. They are the best in the land at whatever they do.

I have also found them very responsive plus you usually can get comms from Roland via the Yahoo AP group easily.

Greg.

[gregbradley]

OK so I use accurate Polar Alignment not what the report says unless I click on advanced polar alignment. Why is there an advanced or accurate polar alignment?? It implies someone would be satisfied with a non accurate alignment? As-if.

Greg.

[DavidTrap]

Won't disagree with you Greg.

DT

[SpaceNoob]

The adjustments are correct from the wizard, however the reporting is wrong. It's reversed. I found this last night after performing the MKS5000 upgrade on my PME over the weekend, obviously destroying the existing polar alignment.... the marker I placed on the mount, fell off while I was pulling stuff apart, only realised the sticker had come off when I was beginning the polar alignment process. A few hours scratching my head and wondering if ripping the guts out of the mount had been a bad idea. Their wizard works, just center the star, the adjustments you apply will likely be reversed to what they report. Also, probably perform the "re-calibration" after you make the adjustment. I tend not to trust stuff, so once I zero out polar alignment I perform a new synch and build my bigger model from the accurate and polar aligned synch.

Pretty happy with the upgrade, now I have an obese PMX, all the mechanical aspects that I love about the PME, with the usability and smarts of my trusty PMX. I'm still yet to build a new large point model and apply PEC, but it turns on, homes, synchs, slews and has worked perfectly so far!

[PRejto]

Hi Chris,

My understanding is that after "accurate polar alignment" it is not necessary to recalibrate the model. The model knows that you moved the mount, and since the move is exact (unlike just using the tic marks on the adjusters) it updates itself. Patrick Wallace has said a recalibration after is totally unnecessary.

Peter

[SpaceNoob]

Sorry dude, not from my observations. Your synch stays where the original synch was, I start from there and build a new one after I finish the alignments. Else, you'll notice that while your pointing is repeatable, it will be offset by the last adjustment you did after you conduct a home/switch off the mount. I spent a lot of time trying to isolate this issue, deployed various time solutions as I initially thought it was time source based. I could be wrong, but thats my process and it works, I don't end up with a silly offset. I've seen it on both the PME and PMX, MKS4000 and MKS5000.

edit:
Just to re-iterate, once i've done a few runs and perform my last polar alignment adjustment using the wizard, I blow it all away, do a new synch, then build my actual model.

[gregbradley]

Oh great, that's great news - not.

I am in the middle of a 300 point T-point model. I suppose I'll see how it works as it says that the model has taken it into account but I believe you.

Greg.

[gregbradley]

What's the advantage of the MKS5000 over the MKS4000 on the PME?
Apart from the nicer singing tone that it makes hehehe.

Greg.

[PRejto]

OK, whatever floats your boat. But, I'll say that the latest posts by Mr. Wallace say quite different things, especially about syncs. Contrary to the manual he advises not to have any sync at all. He said that the only reason SB recommends a sync is in case PA is not good enough to get an initial plate solve. The model itself serves as the sync if you will. I haven't had a sync in TSX for a long time now. Obviously your mileage may vary. In saying that, why not put up a post at SB about your experience? If your observations differ from what is being preached there I think it's important to share it so others can benefit.

Peter

Edit: Obviously your method works, no doubt. However, I think more than a few might think it completely unnecessary to delete your model and start over just because you adjusted PA. A recalibration into your model will save that model by updating the terms that changed when you moved the alignment. I think you would find this works quite well if you just don't have a sync. What I do is add the first point of a new model by hand (without any sync). Then I just run an automated collection, super model, accurate PA, done.

[PRejto]

Some people would argue none since there is no longer any serial connection, only USB. I seem to remember that this was, and may still be, causing issues for remote imagers. Something about having only one way to access the mount remotely in case there is an error. Not sure. I just remember a whole slew of posts where many were unhappy to not have a serial connection + USB.

Peter

[SpaceNoob]

Actually, the singing tone is a bit muffled lol.... the board sits pretty deep inside the mount. I did have a chuckle when it homed and made the MX sound I was used to before.

Colder conditions MKS5000 is supposed to have improved track rates etc. It gets very cold inside my observatory during winter, even with a dome, ice everywhere lol.

USB through the mount, Power through the mount with more modern cabling options. I preferred the PMX for cabling in general, but appreciated the much larger internal spaces for cabling through the mount; however, running chunky cables through the inside during summer was fine but as things started getting crazy cold stuff gets a lot stiffer. There are also a bunch of keystones I can expand upon but I'll figure that out later.

New hand paddle, I prefer it over the older one.

Mainly, I wanted to ensure that the mount was somewhat modernised as a baseline for the new image train that has just arrived.

During the upgrade I pretty much pulled the entire thing apart, inspected everything I could get to. After re-assembly and initial power on tests / TCS configuration, I performed spring plunger adjustments based on load I'll be placing on it.

Tonight I collected PE data, seeing was fairly crappy before the big cold low system slams through here. PEC applied, all seems fine, though I'll grab another run once the weather improves.

PL16803 is now on the back of the CDK, dark library is sorted, mount is mostly done, SX Lodestar X2's calibration masters are ready. Now I just need the new gear weather curse to pass :lol:

[SpaceNoob]

My polar alignment models are around 80 points, I do this probably twice, depending. The first being a larger adjustment and the last intended to get as close to 0/0 as I can. The wizard works very well, best thing they've added IMO. Since I first got the PMX in 2012, southern hemisphere routines were always bugged with reversal issues. This latest bug is just an indication of insufficient functional testing being performed on code that they push out. Simple test cases should have identified it.

The process I follow:

1 = Home mount
2 = Expose image after homing and synch directly to the image.
3 = Automated tpoint collection using 6 points near synch position
4 = remove the user added 6points from the list and then extend it out to say 50-80, whole sky.
5 = finish tpoint, generate super model and apply it.
6 = Perform polar alignment wizard adjustment against a star with ~98+% reliability.

start process again, but with 200+ points and finish at super model.

If the above is wrong, I am happy to do try something else but synching to an actual plate solved image seems far more reliable than rough eyeball, especially when you switch off your mount and re-home it.

[gregbradley]

My experiences with sync recently seem to show that Syncing is a touchy thing.

The mount got bumped when I was adjusting some heavy counterweights and moved it slightly.

Go-tos from a 100 point model were now badly off so I did a new sync.

Now the scope was trying to point to the northern hemisphere in go-tos. It took me a while to understand what was going on. I had to click on set to southern hemisphere again (even though the software said it was set to southern hemisphere) and then all was good again.

The bottom line is Sky X is northern hemisphere-centric. It does not like us southerners and kind of lets us play reluctantly. Its not the first time we have been second tier citizens with regards to it working in the southern hemisphere.

Next time I do a T-point (please Astro Gods, not for a while!) I will try it without a sync as I can see it may introduce a bias to one area of the sky.

Greg.

[SpaceNoob]

I'll try without a synch too. I've only done a small model.

I also noticed that clearing synch resets it to Northern hemisphere.... Northern centric is not an excuse for these issues. Again, simple testing of their software prior to release would have identified it. No need to be in the Southern Hemisphere to click a few buttons and observe parameters. Dodgy software is a complete joke in this industry.

[PRejto]

Chris,

I wasn't clear enough when I said I didn't sync but added a point manually. What I ought to have said is that I add a single point that is the center point of a plate solve.

Greg, there may be some other bug that has not been fixed . A guy with a very good T-Point model in place has reported that Protrack seems not to be working correctly. Then another poster pointed to an older thread by our friend Josh that showed that sometimes Protrack corrections were not being applied even though both check boxes were enabled. But, turning Protract off and then back on temporarily fixed the problem. Something similar might still be going on occasionally. So, if you get RA drift with Protrack on just try the off/onn technique to see if suddenly Protrack works as expected.

Peter

[SpaceNoob]

Ok that makes a lot more sense, I interpreted it a little different / dodgy haha, apologies. ;)

This pro-track thing does bother me, I have observed similar behavior and have to admit that I kept pro-track turned off for many months. Using the AO unit on the SBIG, I found that with 30min subs, not one single "bump" was required, so I felt comfortable with it off as my tracking didn't really have any noticeable drift that the AO couldn't handle over long durations, or at least in a 30min period.

Now I'm back to OAG operation with the MMOAG, so with Pro-track's ability to counter a lot of other variables I'd like to know it actually works lol

[gregbradley]

So that advantages are mainly the better USB options, power outlets and hand controller same as PMX. Yes that does sound good.

I wonder if that all adds up to better tracking or just nicer to use with the power outlets, usb and hand controller.

You use Maxim for controlling your Lodestar? I use CCDsoft still and you can't use a library dark with the Lodestar which it absolutely needs. For that reason I use SBIG STi.

Greg.

[gregbradley]

Last night I activated Protrack and it sent a mad spike of error every now and then. I was getting guiding 0.00 to .3 errors, often around .1 and then with Protrack on I'd suddenly get a 6.0 error.

With my PME, Protrack helps get rounder stars. So it can help at times.

I'll try the turn it on and turn it off a few times approach.



Greg, there may be some other bug that has not been fixed . A guy with a very good T-Point model in place has reported that Protrack seems not to be working correctly. Then another poster pointed to an older thread by our friend Josh that showed that sometimes Protrack corrections were not beig applied even though both check boxes were enabled. But, turning Protract off and then back on temporarily fixed the problem. Something similar might be going on stiil on occassion. So, if you get RA drift with Protrack on just try the off/onn technique to see if suddenly Protrack works as expected.

Peter[/QUOTE]

[SpaceNoob]

Correct, I use Maxim DL6 now for camera control. With the SBIG I use TSX camera add-on as I found Maxim a complete joke for SBIG AO control.... go figure lol.

I use Maxim because I want to be able to automate focus, platesolve, dark, sub, etc under separate acquisition modes. i.e RBI, non RBI, slow, fast, etc. Even just performing slew runs and platesolves, the camera read noise is so low that RBI stands out clear as day.

Not yet had it running for imaging yet, just testing etc, but so far so good. It's a bit of a beast to get my head around but starting to make sense of it. SX Lodestar X2 has a calibration library configured now, I didn't need a bad pixel map as there were no hot pixels to deal with; however it has been icy cold inside the observatory and that likely helps. Dark / Bias masters have been fine so far for a few guide tests, maxim seems to scale them quite nicely when required.

Note, I don't intend to use Maxim to auto calibrate my subs, I'll do this manually, but for OAG it can do what it likes.

[gregbradley]

Sounds like a very solid routine. Do you clear your sync history or simply do a fresh sync on top of the older ones?

I haven't been doing a fresh sync when I start a new T-point model. Just using the last one done. Not sure what the manual says on this point.

Scrubbing the sync history clean though is what caused my mount to act as if it were set to Northern Hemisphere even though in the BCS it said it was set to the Southern Hemisphere.

The accurate polar alignment feature is a nice new feature and it seems to give superior results.

Greg.

[frolinmod]

Please download and install the latest daily build that was released today.

[gregbradley]

Thanks for the tip.

Quite a long list of fixes. But the Southern Hemisphere Polar Alignment report is one of them plus it mentions getting rid of
ambiguity about software slew limits.

Software slew limits is often a pain for me. I have to set them every time I turn on the Sky X. I usually use -0.5 hours and 0.5 hours.

If I want to slew way past the meridian or usually more safely, I image from way east of the meridian and all the way to the west. I set that then to the 2.5 hours max so long as its clear the filter wheel won't hit the pier.

Is it best practice to do a save when you exit. It doesn't ask if you want to save when you exit like Sky 6.0 did. Also there is a set up Profile option in the menus which I don't know what that does but perhaps you enter your setup and it saves all that for future reference?

An suggestions on slew limits?

I found it was causing a percentage of Tpoint points to fail. I would get slew limits exceeded when I wasn't anywhere near the limit. Odd.
Setting limits to 1.5 hours seemed to stop a lot of that though. I was getting lots of fails and it could mean my model is skewed because some directions don't get added by this quirk.

How do you set your limits? Perhaps I should slew the scope to the max physically then use the current position button for each side rather than adding a number. It also changes one of them to a - .

Greg.

[PRejto]

Greg,

That's how I set my slew limits. I put the scope in the max safe position and set the limit to the current position. Other than that I didn't do anything

I noticed one thing that had some points fail in a T-Point run recently. I didn't notice that I'd accidentally added a couple of user points that were outside my slew limits. They are red and don't stand out from the rest of the points so well, particularly if you are not looking for them. Fortunately they can be deleted from the drop down menu easily.

Peter

[gregbradley]

Thanks Peter.

I plan to do that next time as the fails from slew limits are a pain.
I didn't know points outside the limits display as red. I'll look out for that.

I've downloaded the latest Build 9037 and we'll see how we go. My TPoint model seems perfect now so it will be next time I need one (hopefully not for a long time, too much mucking around and not enough imaging!).

Greg.

[PRejto]

I think all user defined points are reddish color whether they fall inside or outside of slew limits. I just happened to have a couple that were outside my defined limits that I didn't notice.

Peter

[gregbradley]

Yep I get that. I just misread your original post.

Greg.