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Skywatcher EQ-5 Pro Question

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#1 Steve Darden

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Posted 16 January 2010 - 08:27 AM

I just received my new mount and I have a strange question. On the Dec axis there is a part in front of the polar allignment scope that connects the counterweight bar to the mount saddle. Depending on the the rotation of the axis the polar allignment scope is either blocked or not. On my mount, in order to be able to look through the polar alligment scope (not blocked) I have to rotate the telescope tube perpendicular to the dec axis. Shouldn't both the telescope and the polar axis be pointed in the same direction when you are polar aligning the scope? What am I missing here?

#2 rmollise

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Posted 16 January 2010 - 09:17 AM

I just received my new mount and I have a strange question. On the Dec axis there is a part in front of the polar allignment scope that connects the counterweight bar to the mount saddle. Depending on the the rotation of the axis the polar allignment scope is either blocked or not. On my mount, in order to be able to look through the polar alligment scope (not blocked) I have to rotate the telescope tube perpendicular to the dec axis. Shouldn't both the telescope and the polar axis be pointed in the same direction when you are polar aligning the scope? What am I missing here?


No. They don't have to be, and there would be no practical way to do this with a polar borescope. This is normal for almost all GEMs (a few have had polar scopes mounted to the side of the RA housing, but that really doesn't offer an advantage). Polar align your scope with the OTA perpendicular to the RA axis, and when you are done return it to home position and do your go-to alignment.

#3 Steve Darden

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Posted 16 January 2010 - 09:19 AM

Thanks Rod. The only other EQ scope I have used is an EQ-3 and it doesn't have anything blocking the polar scope. It just seemed weird to me. Thanks again.

#4 John J

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Posted 16 January 2010 - 09:32 AM

They turn the scope perpendicular to the polar alignment bore hole because if it was in line, and you had a long refractor or any scope for that matter, you wouldn't be able to get your head between the polar scope and the big scope.

JJ

#5 Steve Darden

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Posted 16 January 2010 - 09:44 AM

John, that makes sense. I hadn't though of that. Thanks for the info.

#6 John J

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Posted 16 January 2010 - 10:02 AM

Another point too is if the scope is perpendicular to the polar bore, you can rotate the RA axis a full 360 to get at the polar offset mark without hitting the tripod.

JJ

#7 BKBrown

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Posted 16 January 2010 - 11:21 AM

Another point too is if the scope is perpendicular to the polar bore, you can rotate the RA axis a full 360 to get at the polar offset mark without hitting the tripod.

JJ


I have actually had some issues with this lately. With Cassiopeia and the Dipper in their current positions early in the evening, I have not been able to rotate the head enough to get an exact visual correlation. It hasn't been an issue though because I always get the proper position for Polaris from PolarFinder before going out so I know where it needs to be. I totally concur with other comments in this thread, the feature is pretty much standard on mounts with polar scopes. Clear Skies, BrianB.

#8 Steve Darden

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Posted 16 January 2010 - 11:35 AM

Thanks everyone. I have to say that I'm impressed with the look and strength of this mount so far. I recently purchased a C8 and this mount seems to handles the weight perfectly. It should be perfect for visual use and outreach events. I haven't had a chance to use it yet...still need a battery. The strength to total mount weight ratio was my major consideration when buying this mount. I would give up a little stability for ease of set up (less weight) and so far this mount seems perfect in that regard. Seems very solid with this load.

#9 John J

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Posted 16 January 2010 - 11:37 AM

I also use PolarFinder to improve my initial polar alignment. I only use my EQ mount for astro photography. I find it reduces my drift align time and is so close sometimes that I don't even make an adjustment. I just let the auto guider take care of the guiding.

JJ

#10 Starhawk

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Posted 16 January 2010 - 11:44 AM

Has anyone used the PEC on these mounts? That is my main question in regard to its real feasibility for astrophotography with little scopes (I mean 80mm and smaller ED tubes). How about autoguiding with the Orion autoguiders? If the software appears to be predictable and stable, and does permanent PEC retention, that would be of interest to me.

-Rich

#11 John J

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Posted 16 January 2010 - 11:51 AM

I have the EQ-6 mount. I don't use the PEC when auto guiding with PHD and the SSAG as the two can get in a fighting match. I have found that after PHD does it's calibration, it compensates for backlash and guides out the PE.


JJ






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