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Help with a new iEQ45

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#1 1074j

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Posted 06 December 2012 - 11:56 AM

I've just moved up to a iEQ45 from a Alt-Az mount and am having a issue with polar alignment. Using the alignment scope, along with a level mount, I've been able to get what looks like a good alignment as when rotating RA by 90 or 180 degrees, Polaris remains in the same position in the alignment scope. However, when viewing through a correctly aligned finder scope, I find that Polaris is barely within the view and am guessing that the error is around 3 degrees. At first, I though it was an issue with cone error of the 8" SCT, but I have the same problem with a new scope, a 11" SCT and now suspect something is wrong with the mount. I'm going to attempt my first drift align, hopefully tonight, to try and narrow down the source. Any other advice? Thanks.

#2 psandelle

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Posted 06 December 2012 - 12:13 PM

GPS working right (maybe manually put in the location and time to check)? Level straight up on the polarscope before starting? Is your head straight up when looking in the polar scope (I once glanced in from the side and got things sideways for a second once)? You SURE the finder scope is aligned? Are you sure the polarscope is aligned (there's a good tutorial somewhere online about that)? What happens if you align the finder scope with the polar scope?

Now, for me, I think Polaris will rotate slightly when the RA is rotated, as the scope isn't pointed straight at Polaris, but takes into account the North Star being off-set. But don't quote me, as I've never tried that. I usually get pretty good rough Polar from my polarscope on the iEQ30 (and then: Alignmaster!).

Those are my first thoughts; I'll keep thinking.

#3 mgwhittle

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Posted 06 December 2012 - 12:15 PM

Let me make sure I am understanding the problem. Polaris is centered in your polar alignment scope at the intersection of the crosshairs reticle (not polar aligned), but you scope's finder, which is aligned with the main OTA, is not centered on Polaris? The key here is whether you mean Polaris is centered in your polar alignment scope or you are actually polar aligned.

#4 1074j

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Posted 06 December 2012 - 03:30 PM

I'll check all those things again, but my initial answer is "Yes" to all of those. That isn't to say that the newbie didn't miss something. I will do a drift align to shed some more light on the issue. Thanks.

#5 mega256

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Posted 06 December 2012 - 04:28 PM

Down load the book.....Dont do the 2 star align...they are working on a fix..The one star works fine at this time.
When you are properly aligned,the polar scope circle,in my case 40 is where polaris is located and the "clock" number,like 9 oclock,is displayed in the hand controller.That is where the north star will be set to,not the center.Dont worry about cone error now untill you
get much closer..It should work if things are proper.I just got my mount last week and its fine.
Have fun,,CS,
There is software that tells how far of NP you are,but use it with 3 star.I find the polar right on.

#6 Phillip Easton

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Posted 07 December 2012 - 08:01 AM

I agree it doesn't sound like you are using the polar scope correctly to do the polar alignment. Make sure you are going through process described in the manual, which you can download from iOptron support.

I also offer a least of tips that I have collected from various sources here: http://www.the3dwiza...5/initial-setup

Cheers!
Phillip

#7 Astronewb

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Posted 07 December 2012 - 11:31 PM

Perhaps this will help you through the PA process..?

My setup procedure with a view of Polaris to minimize offsets and trailing:

With the mount leveled and the latitude correctly set with my Ipad Clinometer.

Using the polar scope..first CENTER Polaris in the reticule using the alt/az adjusters on the mount.

With the OTA mounted, center Polaris in your eyepiece (or illuminated reticle ep),and/or your camera live view screen, by unlocking your DEC and manually centering it (side to side). If your ota plate has adjustable screws for cone error you can dial it in to center (up and down), otherwise, just settle for the center of the ep..it may be higher or lower.

If you are using a guide scope, enable the bullseye overlay and center Polaris in the guidescope.

Now the polar scope, the ota and the guidescope are all centered on Polaris.

Now, using the polar scope, adjust Polaris' position to the correct spot on the reticle, based on the Polaris position readout in the hand controller.

Shut the mount off and turn it back on...you now have a correct 'zero' position.

Now you can perform the 2 or 3 star alignment routines with minimum offsets. I use my guidescope bullseye to center the alignment stars. After the second, or third star is centered, it will give you your polar offset. If it says 3' lower - 6' east, it means you must adjust your mount alt/az to raise it 3' and 6' west.

I am usually able to get to 00-00 within 3-4 iterations of the above routine. This will give you 1-3 minutes of unguided exposures typically.


Hope it helped...

Paul






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