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iOptron GotoNova Kit

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#51 nitrohepcat

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Posted 19 April 2009 - 09:38 AM

I am using a VixenGP with an Ioptron GOTONova EQ Conversion. The scope is a 4" f9 refractor.
Although I am very careful in setting the time/date/location (using Googlemaps and a clock that updates with a built-in shortwave radio), making sure the mount is level, accurately setting the polar alignment and doing a 3 star alignment - the pointing accuracy is still not that great. Most objects are about one degree from the center of the FOV.
Is adding the GPS antenna a worthwhile option?
When synching to an alignment star nearby the object I'm looking for - do I do a choose ALIGN and then perform a 1 star alignment on that star?
How can I check the alignment of the telescope tube to the mount?

#52 Telescopeman54

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Posted 20 April 2009 - 12:47 AM

Is it off by exactly the same amount each time or does it vary? Have you done a GOOD polar alignment? Do you have a solid dovetail and is everything tight? Are the spur gears meshed correctly and are they lubricated?

If you location data is accurate to within several hundred meters/yards then the targeting should be darned close. Check all of the above questions carefully.

Steve

#53 nitrohepcat

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Posted 20 April 2009 - 04:37 PM

The distance between the center of the FOV and the target object varies.
The polar alignment is good.
The location data is within 200 feet.
The dovetail is solid.
The gears have no grease on them. Well, that could be my problem. I'll put some grease on them the next time it's clear.
With regard to the gears meshing correctly - They seem to be meshing OK. I adjusted the backlash with the hand controller and it works OK. Is there a measurement I should be making on the gear to gear interface?

#54 nitrohepcat

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Posted 20 April 2009 - 04:51 PM

Also, the correction factor displayed when I did a 3 star alignment was:
Altitude 246.3' lower
Azimuth 367.9' east
I double checked my observing notes from past sessions and these correction factors are typical.

I was also very careful with the polar alignment and double checked it with the telescope tube and counterweight attached. In the past I've done a drift align after polar alignment, with similar results.

#55 Telescopeman54

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Posted 21 April 2009 - 12:10 AM

The gears are best spaced by placing a piece of printer paper in between them to use as a gauge. Turn the motor to get the paper out when you are done.

It sounds as if you may need to update the controller. The latest firmware along with the downloader program is on the iOptron web site.

Did you set up the controller with the correct UT offset and is there a check mark set next to the Daylight Savings line?

Drop me a line via email if you need further information or help.

CS

Steve






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