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AVX Calibration Stars - Function?

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#26 cn register 5

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Posted 12 July 2013 - 01:41 PM

Wrong. Try it.

Chris

#27 Alph

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Posted 12 July 2013 - 02:11 PM

Wrong. Try it.

Chris

Wong what? Read this

#28 cn register 5

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Posted 12 July 2013 - 02:17 PM

If you had read the thread you would see that we are talking about calibration stars, not the calibrate function.

Chris

#29 jrcrilly

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Posted 12 July 2013 - 02:42 PM

Wong what? Read this


Yup. Just what I said.

#30 freestar8n

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Posted 12 July 2013 - 03:03 PM

I was talking about the dec. offset. Dec. is not discussed anywhere in the referenced link - so your comment has no relevance to the point I was making - and to the importance of calibration stars to all-sky pointing.

Frank

#31 Stew57

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Posted 12 July 2013 - 03:45 PM

Simple test. Set the dec index mark as accurately as you can. Do a 2 star alignment with no calibration stars. Take note of pointing accuracy.

Next turn the mount off and set the mount so the dec index mark is off. Do the 2 star alignment with no calibration stars again taking note of the pointing accuracy.

If there is a great difference in pointing accuracy you are correct. If there is no difference you are wrong.

I always thought both the offset in ra and dec from perfect were corrected for in the sky model by the 2 initial alignment stars.

Do you any "evidence" to show this is incorrect?

#32 freestar8n

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Posted 12 July 2013 - 03:54 PM

Sure - set the dec. offset away by a small value like 1 degree - since it doesn't really matter anyway. Then do a 2-star alignment, then go around the sky and point at objects. Might as well offset it by 10 degrees since it only affects pointing to the first two stars - according to some theories. Since people think cone is so important - go ahead and leave it at the exact value it thinks it is.

But just don't add any calibration stars, since the mount will then try to figure out what the real dec. offset is - and correct for the error based on where the stars really are.

Frank






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