Jump to content


Photo

Help needed with an Advanced GT CG-5!

  • Please log in to reply
22 replies to this topic

#1 Jerry Hyman

Jerry Hyman

    Messenger

  • -----
  • Posts: 491
  • Joined: 29 Mar 2007
  • Loc: Mesa, Arizona

Posted 05 March 2011 - 09:55 AM

I have had this mount for about two years and it has worked just fine. Last night I set it up -- leveled the tripod after polar aligning etc.--- then went through the alignment process and it worked ok but was a little off on going to Procyon. I then rebooted and went through the process again and instead of coming up with Capella as the first alignment star it came up with Sirius. When it went to Sirius it went in the correct direction to the south east but it tried to aim the scope below the horizon. I then started all over double checking my GPS coordinates, time, date, etc. and the same thing happened. I then replaced my power supply and the exact same thing happened.

Help....what is the problem and what is the fix?

Thanks in advance!

~jerry

#2 rmollise

rmollise

    Hubble

  • *****
  • Posts: 15377
  • Joined: 06 Jul 2007

Posted 05 March 2011 - 10:37 AM

I have had this mount for about two years and it has worked just fine. Last night I set it up -- leveled the tripod after polar aligning etc.--- then went through the alignment process and it worked ok but was a little off on going to Procyon. I then rebooted and went through the process again and instead of coming up with Capella as the first alignment star it came up with Sirius. When it went to Sirius it went in the correct direction to the south east but it tried to aim the scope below the horizon. I then started all over double checking my GPS coordinates, time, date, etc. and the same thing happened. I then replaced my power supply and the exact same thing happened.

Help....what is the problem and what is the fix?

Thanks in advance!

~jerry


_Assuming_ your battery (fully charged?) and cable and connectors are good, do a Reset to Factory Values. You'll need to reenter your information, of course. Also be aware that if the star was nearing the Meridian, the mount _will_ take the long way around and will seem to be going off on a dadgum tangent. ;)

#3 Jerry Hyman

Jerry Hyman

    Messenger

  • -----
  • Posts: 491
  • Joined: 29 Mar 2007
  • Loc: Mesa, Arizona

Posted 05 March 2011 - 10:58 AM

The batteries were fully charged. I am going to purchase a new cable this morning from Radio Shack that was mentioned in another thread. I will try the reset tonight.

Thanks Rod!

~Jerry

#4 rdandrea

rdandrea

    Mercury-Atlas

  • *****
  • Posts: 2860
  • Joined: 13 Jun 2010
  • Loc: Colorado, USA DM59ra

Posted 05 March 2011 - 02:00 PM

Try the Reset before you plug in the new cable, otherwise you won't know which of the two solutions fixed your problem. That kind of stuff is handy to know.

#5 rmollise

rmollise

    Hubble

  • *****
  • Posts: 15377
  • Joined: 06 Jul 2007

Posted 05 March 2011 - 02:01 PM

The batteries were fully charged. I am going to purchase a new cable this morning from Radio Shack that was mentioned in another thread. I will try the reset tonight.

Thanks Rod!

~Jerry


More important than the cable is the connector, the scope-side connector. If it does not fit firmly, spread the pins a little with a small screwdriver of a knife.

#6 Jerry Hyman

Jerry Hyman

    Messenger

  • -----
  • Posts: 491
  • Joined: 29 Mar 2007
  • Loc: Mesa, Arizona

Posted 06 March 2011 - 12:43 AM

Even though I picked up a new connector at Radio Shack I didn't need to use it. I went into the menu's and did a factory reset and that corrected the problem. Goto's and tracking was excellent. The goto's were accurate enough to put the objects into the field of a 6.5mm 60 degree eyepiece.

Thanks a bunch guys!!!!!!!!!

~jerry

#7 RTLR 12

RTLR 12

    Skylab

  • *****
  • Posts: 4498
  • Joined: 04 Dec 2008
  • Loc: The Great Pacific NorthWest

Posted 06 March 2011 - 04:37 PM

Jerry, When it happens again...and it will... Loosen the clutches (Probably RA only) and point the scope at the target star. Then continue with your alignment. Try it and see what happens.

Stan

#8 rmollise

rmollise

    Hubble

  • *****
  • Posts: 15377
  • Joined: 06 Jul 2007

Posted 06 March 2011 - 05:48 PM

Jerry, When it happens again...and it will... Loosen the clutches (Probably RA only) and point the scope at the target star. Then continue with your alignment. Try it and see what happens.

Stan


This may help temporarily, but if the computer needs a reset, it will not help long. And if the problem is cables or a battery it will not help at all.

#9 RTLR 12

RTLR 12

    Skylab

  • *****
  • Posts: 4498
  • Joined: 04 Dec 2008
  • Loc: The Great Pacific NorthWest

Posted 06 March 2011 - 07:02 PM

I have had this problem with both my CG-5 and my CGEM mounts. I have addressed the problems of power and cabling. This has fixed other problems effecting my mounts, but the one described by Jerry, that of the scope pointing in a downward position has continued to happen to both of my mounts. I took the advise given here on CN of doing a factory reset when this happened. This involves a considerable amount of time and it did not always solve the problem. I have found that when this pointing downward problem happens to me, I simply loosen the clutch and move the mount in RA to align the target star and all is as it should be from there on. I then continue with my alignments without any further problems. I no longer waste my time on factory resets. I have nothing more to add other than that on my mounts and in my experience this has worked for me.

Stan

#10 rmollise

rmollise

    Hubble

  • *****
  • Posts: 15377
  • Joined: 06 Jul 2007

Posted 07 March 2011 - 05:50 AM

I have had this problem with both my CG-5 and my CGEM mounts. I have addressed the problems of power and cabling. This has fixed other problems effecting my mounts, but the one described by Jerry, that of the scope pointing in a downward position has continued to happen to both of my mounts. I took the advise given here on CN of doing a factory reset when this happened. This involves a considerable amount of time and it did not always solve the problem. I have found that when this pointing downward problem happens to me, I simply loosen the clutch and move the mount in RA to align the target star and all is as it should be from there on. I then continue with my alignments without any further problems. I no longer waste my time on factory resets. I have nothing more to add other than that on my mounts and in my experience this has worked for me.

Stan


This is not normal behavior. If your mount does this consistently, you should consider having Celestron look at it. I've never experienced this in six years of use.

#11 RTLR 12

RTLR 12

    Skylab

  • *****
  • Posts: 4498
  • Joined: 04 Dec 2008
  • Loc: The Great Pacific NorthWest

Posted 07 March 2011 - 07:56 AM

Rod,

I have seen this problem posted here and on other forums. Jerry describes this problem in his OP. It would seem odd to me that of all of Celestrons mounts I have the only 2 that have the phenomenon pointing to the ground when they should be pointing to the sky.

There are more things in heaven and earth, Horatio...

Stan

#12 Fred1

Fred1

    Vanguard

  • *****
  • Posts: 2037
  • Joined: 19 Sep 2007
  • Loc: Somewhere in the Orion Spur

Posted 07 March 2011 - 09:30 AM

I've had that problem when I had my Nexstar SE mount and on a few occasions with one of my CG5s. The cause was always an input error. I recall finding that I had input the wrong date or wrong time zone and another was an incorrect alignment star. The latter resulted after I scrolled to an alignment star other than what the HC first selected and I obviously aligned on the wrong star. Apparently, the sky modeling just goes nuts when I do that.

#13 RTLR 12

RTLR 12

    Skylab

  • *****
  • Posts: 4498
  • Joined: 04 Dec 2008
  • Loc: The Great Pacific NorthWest

Posted 07 March 2011 - 10:46 AM

The error I'm experiencing is approximately 70° misalignment in RA. I hardly think such a large error can be caused by incorrect data input like the wrong time zone. The data input has been through both manual input and CN16 GPS input. Both have been checked and reentered numerous times and also by data base input means. I am fairly familiar with the sky and I know that Rigel is not 40° below the horizon on the 5th of March at 2100hrs on the west coast of America. I would have to disagree on the statement that "...the sky modeling just goes nuts..." in this case, because I can simply loosen the RA clutch and point the scope at Rigel and continue the alignment just as if the mount had pointed to Rigel itself. Once I have aligned on Rigel and chosen an additional alignment star the mount reacts normally and with proper accuracy. The second alignment star is always well within the FOV of the EP as too are the subsequent calibration stars. This has happened a multitude of times on both my CG-5 and my CGEM mounts.

Stan

#14 jrcrilly

jrcrilly

    Refractor wienie no more

  • *****
  • Administrators
  • Posts: 33731
  • Joined: 30 Apr 2003
  • Loc: NE Ohio

Posted 07 March 2011 - 10:53 AM

The error I'm experiencing is approximately 70° misalignment in RA. I hardly think such a large error can be caused by incorrect data input like the wrong time zone. The data input has been through both manual input and CN16 GPS input. Both have been checked and reentered numerous times and also by data base input means. I am fairly familiar with the sky and I know that Rigel is not 40° below the horizon on the 5th of March at 2100hrs on the west coast of America.


The RA error is 15 degrees per hour of incorrect time zone so 75 degrees is a reasonable error (5 zones).

If it reports an object below the horizon when it is not, then it can ONLY be a location, date, time, or time zone error and with the GPS it shouldn't be a location, date, or time problem. That pretty much leaves time zone.

#15 RTLR 12

RTLR 12

    Skylab

  • *****
  • Posts: 4498
  • Joined: 04 Dec 2008
  • Loc: The Great Pacific NorthWest

Posted 07 March 2011 - 11:01 AM

So when I enter the time zone as Pacific and as the GPS also enters the time zone as Pacific the mount thinks it's 5 time zones away? What do you think the fix is for that?

Stan

#16 jrcrilly

jrcrilly

    Refractor wienie no more

  • *****
  • Administrators
  • Posts: 33731
  • Joined: 30 Apr 2003
  • Loc: NE Ohio

Posted 07 March 2011 - 11:09 AM

So when I enter the time zone as Pacific and as the GPS also enters the time zone as Pacific the mount thinks it's 5 time zones away? What do you think the fix is for that?

Stan


Does it report the object as below the horizon or just slew inappropriately to below the horizon? If it knows the object is up but slews to the wrong place that's different.

If the initial slew is way off and you slip the clutches to correct it then it will work fine - but it won't know that the initial slew was wrong so it'll keep doing it. If you use the motors to bring it to where it belongs it'll keep track of that large correction and will compensate on future alignments, eventually bringing the error down. If it works properly one day but has a huge first star error the next day, that correction is what isn't working properly and it's probably defective memory in the location used to store the correction factor.

This all presupposes that you always start from the same initial position, of course. Different starting positions will just confuse it.

#17 RTLR 12

RTLR 12

    Skylab

  • *****
  • Posts: 4498
  • Joined: 04 Dec 2008
  • Loc: The Great Pacific NorthWest

Posted 07 March 2011 - 12:07 PM

As far as starting positions go, some times I'm sitting down and sometimes I stand up, but most of the time I'm somewhere next to the mount.­ OK, now that that's out of the way...Yes I start from a 'home' location every time. I haven't used the motors to reposition the mount, because it has been such a large differential in deflection. I will do this next time. Does the mount 'remember' this info from alignment to alignment and power cycle to power cycle? I say again that I have had this same problem with both my CG-5 and my CGEM. I have this problem at my home location and at 3 other locations 40, 100, and 160 miles away. I can do an alignment and then cycle the power and start another alignment and have this problem happen all over again. :shrug:

Stan

#18 RTLR 12

RTLR 12

    Skylab

  • *****
  • Posts: 4498
  • Joined: 04 Dec 2008
  • Loc: The Great Pacific NorthWest

Posted 07 March 2011 - 12:15 PM

Let me add that this problem in no way interferes with the normal operation of the mount. After the mount is aligned it performs flawlessly with no problem in tracking or Go To's whatsoever. It is just a complete pain in the arse when doing an alignment.

Stan

#19 PHampson

PHampson

    Ranger 4

  • -----
  • Posts: 356
  • Joined: 25 Oct 2005
  • Loc: Nashville, TN

Posted 07 March 2011 - 12:18 PM

Mine had this problem of consistently 'remembering' a bad initial position but not nearly as bad as yours apparently. To erase that and get it to remember the newer position, I didn't cycle the power immediately. I would align properly, then send the mount to home position and set it to hibernate, then shut down. Upon restart then, the 'new' position seemed to take and be stored and I could cycle the power or whatever to align as usual. That was the only way it seemed I could get the mount to drop the bad initial alignment and store something else. May be worth a try.


Paul

#20 RTLR 12

RTLR 12

    Skylab

  • *****
  • Posts: 4498
  • Joined: 04 Dec 2008
  • Loc: The Great Pacific NorthWest

Posted 07 March 2011 - 01:13 PM

Thanks, Paul.

I have tried that and I don't remember if that has worked every time or not. Next time I'll pay better attention after a hibernate. I really haven't been able to reproduce nor eliminate the problem on a regular basis. Maybe I need to document exactly what is happening and when every time it happens and see if I can find a pattern.

Thanks so much to you guys for the help. I think I totally hijacked this thread from Jerry. Sorry about that Jerry. I really didn't mean to.


Stan

#21 Jerry Hyman

Jerry Hyman

    Messenger

  • -----
  • Posts: 491
  • Joined: 29 Mar 2007
  • Loc: Mesa, Arizona

Posted 07 March 2011 - 05:54 PM

Stan, my problem appears solved, and I find the comments after that really informative, so hijack my threads anytime you want!

~jerry

#22 RTLR 12

RTLR 12

    Skylab

  • *****
  • Posts: 4498
  • Joined: 04 Dec 2008
  • Loc: The Great Pacific NorthWest

Posted 07 March 2011 - 06:56 PM

Thanks, Jerry.

#23 rmollise

rmollise

    Hubble

  • *****
  • Posts: 15377
  • Joined: 06 Jul 2007

Posted 07 March 2011 - 09:09 PM

Rod,

I have seen this problem posted here and on other forums. Jerry describes this problem in his OP. It would seem odd to me that of all of Celestrons mounts I have the only 2 that have the phenomenon pointing to the ground when they should be pointing to the sky.

There are more things in heaven and earth, Horatio...

Stan


All I can report is what I have experienced and what the people I know who use the mount (extensively) have experienced.






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics