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Declination Setting Circle Readout Error.

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#1 Kraus

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Posted 30 March 2013 - 01:34 PM

Setup;

LX-200 on a wedge. Star drift shows well aligned to the north celestial pole. Optical tube assembly balanced with dew shield, diagonal and an eyepiece attached.

Problem.

As I aim for objects southwards, the declination readout is more southern than the its listed declination.

Example,

With M-42 in the eyepiece, the scale reads near ten minutes of arc more south than M-42's listed declination.

Jupiter's Ghost reads almost 25 arc minutes more south than the object's listed declination.

The more south the object, the more the error southwards.

The problem is reversed for object 40 degrees north or more.

An overhead object's declination readout is correct. It's driving me batty. Any ideas would be appreciated.

#2 rmollise

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Posted 30 March 2013 - 03:18 PM

I wouldn't be surprised to see some errors of this magnitude. How are go-tos?

#3 Kraus

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Posted 30 March 2013 - 08:32 PM

Thank you for your reply.

Go-to?

#4 rmollise

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Posted 31 March 2013 - 09:35 AM

Thank you for your reply.

Go-to?


You did say you have an LX200. It points automatically to objects with the hand controller. But you also have to sync on a star first (in polar mode) to get the accuracy good. Might want to take a stroll through the manual one more time... ;)

#5 Kraus

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Posted 31 March 2013 - 01:57 PM


Thanks again.

I gave up on the automatic polar alignment. Three attempts in a month, I went by the instructions. I push this button pressed that one. Capella and Sirius were the alignment stars. It says 'alignment complete'. I ask it to slew to M-42 and took off to the north. Setting circles have always been my friend. Perhaps the declination disc markings are off at time of production. Machines can make errors. Humans cannot.






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