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ZEQ25GT Tension Adjustment

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#1 TCK123

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Posted 07 August 2014 - 12:30 AM

I was wondering if the Ra and Dec tension adjustments have an effect on unguided exposure length. I normally have the tension adjustment turned out one to two full turns. I have tuned the mount, and polar align using the pole star position on the hand controller. I then do a one star alignment and record PEC. I then turn on PEC and start imaging. I only can take 30 sec exposures, any longer and the stars are not round. I have heard many people say they are getting one to two minute unguided exposures. Can anyone tell me what I am doing wrong.

#2 Mkofski

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Posted 07 August 2014 - 01:15 AM

Have you tried skipping the PEC steps?  I'd do that first.  Do you drift align?  That should help a lot with unguided shots.

 

Different mounts appear to be different as the the tension adjustments but mine works best when I back out the tension adjustments 1/2 turn. 

 

Mike


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#3 TCK123

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Posted 07 August 2014 - 01:23 AM

I have not tried to drift align. I will try both of your suggestions. Thanks Mkofski



#4 Seldom

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Posted 07 August 2014 - 05:54 PM

To elaborate on what Mike said, if you have a newer ZEQ25 you may want to turn the tension screws in tighter.  I got mine last November, and I'm turning the tension screws tight in, and then back off 1/2 turn.  I got a much better PHD2 DEC plot that way.  Apparently, the back off 2 turns recommendation was based on longer screws than are being furnished with the newer mounts.  I've read that when the older, longer, screws were fully tightened they were actually binding on the worm housing.  Also, if you have a smartphone you should try the iOptron app.  It only costs $2, and is a lot easier to read than getting the Polaris location from the handset.


Edited by Seldom, 07 August 2014 - 06:00 PM.

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#5 TCK123

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Posted 07 August 2014 - 08:24 PM

The mount has a 2/14 production date. I will try tightening them up tonight to see where that gets me. I did not know about the app, I will give it a try.

 

Thanks,



#6 calypsob

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Posted 07 August 2014 - 08:33 PM

Use the polar align feature which requires you to slew between 2 stars and adjust altitude or azimuth to center the star. It works great. Why are you not using the polar scope?



#7 TCK123

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Posted 07 August 2014 - 11:32 PM

I am using the polar scope. I was using the polar star position on the hand controller and then adjusting the mount to put polaris in the position shown on the hand controller. it works, but i was still getting trailing on any exposure over 30 seconds.








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