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Sharpstar 61 EDPH II reducer manual rotator causes tilt

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#1 msacco

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Posted 28 October 2021 - 04:15 AM

Hey, I've been imaging with the SharpStar 61 EDPH II for a while, and lately I noticed some issue with the manual rotator in the reducer.

So basically, it's a sort of pressure ring mechanism(without the actual ring I guess...).

Here are some images:

1k2VPuP.png

 

iQMO1s3.png

 

(took from this video - https://www.youtube....?v=5sknuFfbTDQ)

 

So there are 2 metal piece that simply sit together and are held by 3 screws on each side:

czblZAO.png

 

That creates some pressure to hold it together, so it can be just tight enough to hold it but still rotate, but this is where the issue comes, it seems like this causes severe tilt on some degrees.

 

I tried to mess with the screws pressure, make all of them as even as I can etc, but nothing I tried worked.

Did anyone with a sharpstar/raptor 61 experienced this? Are there any solutions for this?

 

Thanks!



#2 OldManSky

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Posted 28 October 2021 - 08:11 AM

Yeah, it's not the best design.  A "ring" that rides in a slot/track would be more stable and easier to align.

However, I haven't had noticeable tilt in my images from the design.  Tighten all the screws equally, and it doesn't tilt -- at least on mine.



#3 msacco

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Posted 28 October 2021 - 08:23 AM

Yeah, it's not the best design.  A "ring" that rides in a slot/track would be more stable and easier to align.

However, I haven't had noticeable tilt in my images from the design.  Tighten all the screws equally, and it doesn't tilt -- at least on mine.

I only noticed it recently actually when all of a sudden I noticed that my stars suck..when I tried to understand why my results show it's because of the reducer's rotator. It could differ from somewhere around 7% tilt to like 20-30%, which is huge.

 

Just like you mentioned, doing the obvious thing which is to make sure everything is tightened equally, but unfortunately that did not help :\

Seems like there is 1 side which is always much worse.

 

I tried to reach out to sharpstar, no reply yet, maybe they could send me a replacement only for that metal part...don't know if this would make any difference.

Any further ideas I could try?

 

Thanks.


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#4 OldManSky

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Posted 28 October 2021 - 11:18 AM

Further ideas...make sure you don't have any marks/"dents" from over-tightening screws, and if you do, move the rotator slightly to avoid those areas.  

Can't think of much else right now, sorry!




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