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Tyranthrax
sage


Reged: 04/22/13

Loc: Reno, NV
tracking question new
      #6262970 - 12/20/13 02:23 AM

So I went through a lot of the old posts and didn't see a solution. I have this happen once in a while, but the goto work, it aligns, but once I center the target, the tracking doesn't keep up. 3 nights ago, after my ill fated wedge incident, I was nuts on tracking left to warm up, 25 min later BAM still in the camera. now I know it has been cold. but the tracking isn't even close. Usually I realign it and it works or at least sync it up. but three nights in a row and nada. I viewed the sun during the day and it was fine. is this a cold thing? Because I gave up when my scope frosted over and I couldn't stand the cold. Like I said most of the time it works just fine, maybe 3 times I've had this happen up till now. Specifics - wedge, 6se and polar aligned. goto works pretty close, nothing out of the normal, but the tracking is slow. like it's not keeping up. is this something stupid like a setting? I've read over the instructions again but nothing. Anger level : severe I almost threw it in the street.

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Tyranthrax
sage


Reged: 04/22/13

Loc: Reno, NV
Re: tracking question new [Re: Tyranthrax]
      #6262994 - 12/20/13 02:54 AM

forgot I'm using the ac adapter. (see a lot of power related issues)

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Tel
Postmaster
*****

Reged: 03/31/06

Loc: Wallingford England
Re: tracking question new [Re: Tyranthrax]
      #6263040 - 12/20/13 05:14 AM

No doubt I'm wrong and if so, will someone please correct me soonest, but in the back of my mind, (and I can't for the life of me find reference to it), I had a notion that when aligning in EQ North or EQ South mode, (i.e. from a wedge), tracking has to be manually switched "on" unlike when aligning in Alt./Az, where it's automatically "on" once the alignment is complete.



As requested, perhaps someone can confirm or refute this notion as I'm certainly unsure of my ground here !

Best regards,
Tel


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Tyranthrax
sage


Reged: 04/22/13

Loc: Reno, NV
Re: tracking question new [Re: Tel]
      #6263054 - 12/20/13 05:44 AM

is that when you go to he menu option and select sidereal I think it is from tracking? I haven't dove into the controller too much. it's weird It worked fine 3 nights ago. I read over the manual, but it has things in i that aren't on my controller. It only happens when I do the wedge. . .I gotta be doing something wrong.

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Tel
Postmaster
*****

Reged: 03/31/06

Loc: Wallingford England
Re: tracking question new [Re: Tyranthrax]
      #6263073 - 12/20/13 06:23 AM

Tracking settings are available when you go into the "Menu", select "Tracking" and then "Mode".

Mode gives you the option of Alt./Az, EQ North, EQ South or Off for alignment purposes. Rate, on the other hand, provides for Sidereal, Lunar and Solar tracking speeds.

But you can easily check whether your mount is tracking at all even in broad daylight and in the comfort of your own home by, having placed it on your wedge, pointing the OTA roughly in the direction of North, elevating it to the approximate position of Polaris and then performing a mock one star EQ North Align, making absolutely sure initially that you have selected that specific "EQ North" tracking mode.

When you have completed this operation and got an "Alignment Successful" indication, select "Utilities" from the "Menu" and then select "Get Axis Position". This will bring the 'scope's position in both Right Ascension and Declination to your HC's screen with two sets of numbers.

If the RA number is seen to be ever changing, then the mount is tracking.

Other issues might also be effecting what you are experiencing such perhaps as backlash, but try the above first.

Best regards,
Tel


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Tyranthrax
sage


Reged: 04/22/13

Loc: Reno, NV
Re: tracking question new [Re: Tel]
      #6263099 - 12/20/13 06:59 AM

I did see that as eq north, so I figured it was fine. I saw something in the manual about wedge alignment but didn't see it as an option

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Tel
Postmaster
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Reged: 03/31/06

Loc: Wallingford England
Re: tracking question new [Re: Tyranthrax]
      #6263123 - 12/20/13 07:32 AM

Don't worry about "Wedge Align", just ensure that you've selected EQ North, if you are proposing to align your scope on your wedge, and carry out the above suggested mock alignment. This will tell you whether your scope is tracking at all. We can then work from the result you obtain.

Best regards,
Tel


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setiv2
member


Reged: 03/28/13

Re: tracking question new [Re: Tel]
      #6263286 - 12/20/13 09:41 AM

I had my tracking turn off while I was EG North aligned before as well. It happened when I mis-hooked up everything to start autoguiding. I was aligned and ready to go, plugged the computer to the HC, pulled up PHD and also pulled up the NexRemote. As soon as the computer hooked up with the mount it shut the tracking off. Spent forever trying to figure out why it wasn't tracking, gave up that night, then in the morning had an epiphany to check the tracking under the HC mount menu.

Long story short I agree with Tel about probably your tracking was turned off somehow. Quick fix.


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Midnight Dan
Postmaster
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Reged: 01/23/08

Loc: Hilton, NY, Yellow Zone (Bortl...
Re: tracking question new [Re: setiv2]
      #6263299 - 12/20/13 09:49 AM

Just in case the tracking was not turned off, there's a couple of other things you can look at.

First, the clutch could be slipping. When it gets cold, the parts shrink slightly and the clutch has less pressure on it. When the clutch is not quite tight enough, it can show up first when its cold. If you think this might be the case, look in the sticky notes at the top of the forum for info on tightening the clutch.

The other thing that comes to mind is backlash and goto approach. Depending on which direction your final approach to the target is, and how much backlash you have, when you stop at your target the motors can be running but the scope not moving because it is taking up the backlash in the gears. If this is the case, the scope will eventually start moving again, but it may take 30 seconds or more. The fix here is to adjust the backlash settings in the menu, set the goto approach direction correctly, and if you use the arrow keys to move the scope you also need to be sure to do your final approach to the target in the same direction.

-Dan


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Tyranthrax
sage


Reged: 04/22/13

Loc: Reno, NV
Re: tracking question new [Re: Midnight Dan]
      #6263945 - 12/20/13 03:12 PM

wel the thing is always a tad bit off, which is not a problem its sometimes in the view sometimes not, I've learned to live with it. Backlash wouldn't that only affect it all the time and have it drag slightly behind the target? And clutch isn't that only if it hits something? I've never troubleshot a rig, but the thing just tracks too slow, like it moves but the object drifts out of view in a few seconds faster than the tracking. like so fast I spend more time chasing the object than trying to focus the camera.

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Tyranthrax
sage


Reged: 04/22/13

Loc: Reno, NV
Re: tracking question new [Re: Tyranthrax]
      #6264074 - 12/20/13 04:29 PM

is there maybe a different procedure than doing the eq north align for polar aligning? then picking another star having it go to it then polar aligning mount pick?

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Midnight Dan
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Reged: 01/23/08

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Re: tracking question new [Re: Tyranthrax]
      #6264099 - 12/20/13 04:40 PM

Quote:

And clutch isn't that only if it hits something?




When it's adjusted properly, yes. But if it's a touch on the loose side, then it can slip when it is not hitting something.

Quote:

Backlash wouldn't that only affect it all the time and have it drag slightly behind the target?




No. Backlash is the "slop" in the gear train. When you start the motor running, it starts turning ONLY that gear that is mounted on it's own shaft. There will be a tiny gap between that gear's teeth and the teeth of the next one, and it takes some time after the first gear starts turning before the second one does. When you have many gears in the train, that small amount of slop can add up. And when the motor is turning very slowly, it can take a lot of time to take up the slack. Once the slack is taken up, the mount will track accurately and not drag behind the target.

But ... if you change the direction of the motor, then it has to take up the slack in the other direction before the scope starts moving again. You can see this quite easily with your scope by doing the following:

1) During the day, turn the scope on, but DO NOT align it.
2) Put in a fairly high power eyepiece and focus on a distant land target.
3) Set the slew speed to something reasonably slow like 4.
4) use the left and right arrows on the handset to move the scope to the right and then to the left, and then to the right again.

On the first move, you may or may not see a delay, depending on how the gears are loaded at the time. But when you reverse directions, there should be a delay after you push the button till when you see the view move. If you're in a quiet location, during that delay you should hear the motor turning but the scope is not moving. That's when the motor is taking up the slack. More expensive mounts minimize backlash by using worm gears instead of the spur gears used on the SE mount.

Note that if you release the button, and then press the same button again, you should not see a delay because the slack has already been taken up in that direction. Only when you reverse direction will there be another delay.

So ... when you're observing, if you are driving the scope to the left to get the the target, but the motors want to drive the scope to the right to track the sky, then the mount has to reverse the motors after you release the button and you'll see the backlash delay. Through the eyepiece, this looks like the target is moving across the field because the scope is not actually moving. Eventually, the scope will start moving but the target may be out of the field of view by then, especially at higher mags. If you always approach the target in the same direction, and it coincides with the direction that the scope wants to move, then you won't see the delay.

Also, the anti-backlash settings in the scope can help to minimize the effect. It essentially "re-winds" the motors in one direction to take up the slack either at the beginning or end of a slew.

-Dan


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Tyranthrax
sage


Reged: 04/22/13

Loc: Reno, NV
Re: tracking question new [Re: Midnight Dan]
      #6264134 - 12/20/13 04:58 PM

on the clutch I've had to open the thing up to fix a gear issue, I used too long of a bolt and I pushed the drive gear up too far. . possibly I have it too tight? any idea of how much torque it is supposed to be set at?

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Midnight Dan
Postmaster
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Reged: 01/23/08

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Re: tracking question new [Re: Tyranthrax]
      #6264163 - 12/20/13 05:20 PM

From the bolt-in-the-base issue, I assumed you had only opened up the base to get at the azimuth gear. There is no clutch on the azimuth axis.

The only clutch is on the altitude axis which you access by opening up the arm behind the handset holder cavity. I'm guessing you did not open that area up. Correct?

-Dan


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Tyranthrax
sage


Reged: 04/22/13

Loc: Reno, NV
Re: tracking question new [Re: Midnight Dan]
      #6264172 - 12/20/13 05:25 PM

correct. there is the big bolt that tightens down the left right gears. It's pretty snug, the locktite came of so I had no idea where it went. I was playing with the backlash settings. if I am at 4 or 5 it hardly moves when turning even set at 05. I was hoping to get sorted out before heading out tonight.

Going through all the settings making sure things are good.


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Tyranthrax
sage


Reged: 04/22/13

Loc: Reno, NV
Re: tracking question new [Re: Tyranthrax]
      #6264174 - 12/20/13 05:27 PM

heck that one shouldn't matter it holds the stationary gear down OM I haven't slept since last night

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Tyranthrax
sage


Reged: 04/22/13

Loc: Reno, NV
Re: tracking question new [Re: Tel]
      #6264184 - 12/20/13 05:37 PM

Quote:

Tracking settings are available when you go into the "Menu", select "Tracking" and then "Mode".

Mode gives you the option of Alt./Az, EQ North, EQ South or Off for alignment purposes. Rate, on the other hand, provides for Sidereal, Lunar and Solar tracking speeds.

But you can easily check whether your mount is tracking at all even in broad daylight and in the comfort of your own home by, having placed it on your wedge, pointing the OTA roughly in the direction of North, elevating it to the approximate position of Polaris and then performing a mock one star EQ North Align, making absolutely sure initially that you have selected that specific "EQ North" tracking mode.

When you have completed this operation and got an "Alignment Successful" indication, select "Utilities" from the "Menu" and then select "Get Axis Position". This will bring the 'scope's position in both Right Ascension and Declination to your HC's screen with two sets of numbers.

If the RA number is seen to be ever changing, then the mount is tracking.

Other issues might also be effecting what you are experiencing such perhaps as backlash, but try the above first.

Best regards,
Tel




tel I went through this and the numbers are moving, I double checked the settings like you mentioned verbatim and everything is correct and the numbers in the axis are moving. . .

There is a setting for tracking rate, I can increase the sidereal speed if its behind should I kick it up from preset of 50?


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Tel
Postmaster
*****

Reged: 03/31/06

Loc: Wallingford England
Re: tracking question new [Re: Tyranthrax]
      #6264317 - 12/20/13 07:09 PM

It seems to me that the issue here is regularly being clouded by the introduction of too many variables as to make an evaluation of exactly what is happening, exceedingly difficult.

However, from what has already been voiced by Tyranthrax so far, it would seem that his 'scope is indeed tracking but maybe, as a result of possibly poor anti-backlash settings, not as it should.

Could I perhaps suggest therefore that a more "back to basics" testing is adopted and that the 'scope be, for the time being, removed from its EQ mount and the following link be strictly carried out in Alt./Az. mode.

By this means, not only should any backlash problem be addressed, but we should all, in theory, be a little clearer as to whether this 'scope is thereafter, attuned as it should be.

If such tuning can be achieved, then, assuming the securing bolts of the home made wedge no longer impinge on the azimuth gearing as a result of their length and the azimuth gear is free to run as it should, we can set about assessing its further and future performance when, as required, it is as ultimately wedge mounted.

Here's the link:

http://www.cloudynights.com/ubbthreads/showflat.php/Cat/0/Number/5417848/page...

Go, if you think it fruitful, to the 19th. posting down, (by Hamdul) to access the required instructions.


Best regards,
Tel


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Tyranthrax
sage


Reged: 04/22/13

Loc: Reno, NV
Re: tracking question new [Re: Tel]
      #6268686 - 12/23/13 02:10 PM

good news is I went thorough and reset everything. the location was off by a minute on both settings, not sure why I don't have the GPS on it. But I did that and adjusted the backlash, was very thorough on the alignment and I was letting my ocd do it's magic on the set up and allignments. when I did the align mount I was particularly picky this time and think that might have been where I went wrong. but all the things combined tightened it up on the tracking. there was slight movement like super slight, but It was a far far cry better. I'll get it but all these things helped! thank you all!

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Midnight Dan
Postmaster
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Reged: 01/23/08

Loc: Hilton, NY, Yellow Zone (Bortl...
Re: tracking question [Re: Tyranthrax]
      #6268839 - 12/23/13 03:33 PM

Not sure exactly what did the trick but hey, you can't argue with a happy ending!

-Dan


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