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ETX 125 users in Minneapolis/ St. Paul ?

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#1 Shakey422


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Posted 04 December 2019 - 12:59 AM

Looking to find folks locally that can share their experience in person.   The forums haven’t always provided answers but nothing like a little hand on to get some experience.  I’m a beginner looking for help with alignment help.  My scope is always just a little off.  Kinda defeats GoTo.  I’ve read all there is to read with no luck.  So if someone out there wants to get together and make me look stupid I’m game.   I live in Chaska my name is Grant.   Shoot me a message.  Appreciate the consideration.


Thank you


#2 sg6



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Posted 04 December 2019 - 04:12 AM

Many miles and a small ocean away but inaccuracies are usually data and operator related. Have 2 ETX's and know that from direct experience.


As a rule, set your own location, not one of the offered from the Meade list.

Date and Time are easy.

Determine North and Determine Level. - North is not from a compass, so do not use one they are usually a few degrees out.


Level the ETX base by the tripod legs. Again with some accuracy.

Aim the scope OTA North - without anything better use Polaris. If you can put/get/make something to sight along the OTA with that is accurate use that (any good with wood? I made a simple small thin ply+dowel platform to sit a level on the OTA, that helped).


Then it is the 2 star align.


The problem with the ETX125 is simply it is a Mak and a long focal length. You view is narrow.

The software can only assume that your level and North is 100% accurate, so if 1 degree off the first alignment star will be 1 degree off and that is out of view. And that is the problem.


Will now say that Polaris can be 1 degree off of true North so even getting Polaris right can mean the first alignment star is 1 degree out and not in the eyepiece. First thing I bought was a 40mm cheap plossl. Don't care about sharp stars just getting it in the field. Alignment is a pain on all these long focal length scopes.


If you add your own location then I suggest you do a reset, data seems to hang around.


Scope needs a 12v supply, a good 12v supply.


Main aspect is accuracy and so some time and some care.


Add where you are to your profile, easier to read and someone may be local or know a club.


Interesting post over the alignment somewhere. Seems the first level and North to Star1 is to determine how bad you did the Level and North. Then Star1 to Star2 is to determine tilt forward and sideways of the scope. The smaller each is then the better the scope manages it all.


Minor warning: If you do a reset the scope could default to Eq mode not Alt/Az and the tube tries to ram itself into the base. Mine did. So check sort of mount type afterwards and first.

Edited by sg6, 04 December 2019 - 04:20 AM.

#3 Tom3


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Posted 08 December 2019 - 03:26 PM

As SG6 says, careful home positioning is important for doing the 2-star alignment, and it also seems to help tracking as well.  I have a very good (professional grade) compass so I align the OTA in daylight using the compass.  Also adding a green laser pointer helps getting to the alignment stars.  Use an accurate clock to set the time.  If you have a "radio controlled" clock or a gps, use that.



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