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Nexstar 8SE tracking and starfinder questions.

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#1 Tony from Tulsa

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Posted 25 November 2012 - 12:45 PM

Ok guys, I've had pretty good luck in the last two weeks with the scope. But I adjusted the backlash setting yesterday, and it didn't track worth a hoot last night. Should I just put the settings back to zero? I set it to 20 in base (azimuth?) and 10 in the z axis (fork arm?) it seemed to work back and forth in both axis without much slack, though it seemed to jump a little in all directions when I first pushed the directional buttons. Does any of this make any sense to anyone? Also, when I align, it tells me the starfinder is off, but it looks to be pretty close to me. How do I get it closer on center with the scope? It is the stock Celestron starfinder. Thanks for putting up with my rookie questions!

#2 Peter9

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Posted 25 November 2012 - 02:12 PM

Hi Tony,

The backslash settings are best done in the daytime. If you can,focus on a wall or something similar with a pattern. This allows you to see what the scope is doing. Make sure you align the scope first, a mock alignment will do.

Set the slew rate fairly low (I use 3 or 4) and set each axis in turn. Just slew the scope back and forth until you are happy with the Az setting and then up and down to set the Alt setting.

What you are trying to achieve is a smooth pick up and an instant stop in both Alt and Az. It does not matter what numbers you end up with. All scopes are different. Some of the lads end up with very high numbers, mine are 5 and 5.
You will most likely find that you have a delay in the pick up. This is quite normal, I have a 3 to 4 second delay on mine.

The "Star finder off" message is the scope reminding you to turn the RDF off after alignment.

Regards. Peter.

#3 Midnight Dan

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Posted 25 November 2012 - 02:53 PM

Hi Tony:

Your Starfinder Off question made me chuckle because more than one of us has been fooled by it. It means "Turn the Starfinder off", not "The Starfinder is off from alignment". :grin:

Just for terminology, the base rotation is referred to as azimuth (as you suspected), and the fork arm axis rotation is referred to as altitude.

Peter's advice is spot on for the adjustments. The main goal is an instant stop without any jerking back and forth - don't worry about a delay for startup. However, the mount behaves differently before and after alignment. Be sure you adjust for backlash AFTER alignment. If you're adjusting during the day, you still need to do a mock alignment.

-Dan

#4 Tony from Tulsa

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Posted 25 November 2012 - 03:03 PM

Haha!! Starfinder off. I got it. Geez, I'm an idiot. That made me laugh too.
Thanks for the advice, I'll do a mock alignment and set them from there. Or try to, anyway. I appreciate it, guys

#5 Peter9

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Posted 25 November 2012 - 03:36 PM

Hi Tony:

Your Starfinder Off question made me chuckle because more than one of us has been fooled by it. It means "Turn the Starfinder off", not "The Starfinder is off from alignment". :grin:

-Dan


You can count me IN. :bigblush:


Regards. Peter.

#6 Arthur Dent

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Posted 26 November 2012 - 04:54 AM

Ok guys, I've had pretty good luck in the last two weeks with the scope. But I adjusted the backlash setting yesterday, and it didn't track worth a hoot last night. Should I just put the settings back to zero? I set it to 20 in base (azimuth?) and 10 in the z axis (fork arm?) it seemed to work back and forth in both axis without much slack, though it seemed to jump a little in all directions when I first pushed the directional buttons. Does any of this make any sense to anyone? Also, when I align, it tells me the starfinder is off, but it looks to be pretty close to me. How do I get it closer on center with the scope? It is the stock Celestron starfinder. Thanks for putting up with my rookie questions!

LOL

I'd not looked at it that way before but I can see why you thought that.

It is a puzzling message to be sure. Couldn't someone at the big C have come up with "Now turn your starfinder off" instead? Even "Turn your starfinder off" if they were short of space would do rather than the enigmatic message it currently displays.

One of my favourite sayings (although rather depressingly true) is this ...

The big trouble with common sense is ...

... it's not that common!

So come on Celestron. How about fixing this message in the next sofware update? I'm guessing that it isn't that hard to do!

Art

#7 BuckW

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Posted 26 November 2012 - 08:28 AM

Sure am glad to run across this post -- I am new to this and was considering posting the question about remembering to turn off the finder ;-) I have realigned that thing a number of times due to that same message - just knew I was doing something wrong - that was going to be another question.

Thanks to all of you for sharing and your patience.

#8 Midnight Dan

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Posted 26 November 2012 - 09:43 AM

Hi Buck and welcome to the asylum! :crazyeyes: :smarty: :crazyeyes:

Glad our discussion helped with your understanding. Never hesitate to ask a question here, no matter how simple it may seem. We've all been there and are happy to help!

-Dan

#9 Arthur Dent

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Posted 26 November 2012 - 10:05 AM

Hi Buck,

Welcome aboard.

Dan's right, we all have questions at one time or another - but this is the safest forum where you can ask 'em as we never put anyone down and we're happy to help. We were all new too at some point.

Posted Image Posted Image Posted Image

Art

#10 Skip

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Posted 26 November 2012 - 01:13 PM

Yep we all have scratched our heads over that one back in the day! Strange message indeed! I know the message still comes up after alignment, but I don't even see it anymore.






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