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#76 gotak

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Posted 23 February 2018 - 08:59 AM

 

 

 

 

 

It's been pretty obvious from the beginning that some CEM60s have this problem. Not all, but some. And that no tripod or pier will fix it.

 

I'd say more precisely that some folks have had issues but because no one nailed down the root cause, we have no bloody idea what the problem actually is.

 

 

True, but...  I don't recall a single instance of this that was helped in the least with a tripod/pier solution. wink.gif

 

Reading through most of the reports on here they seem to have 1 thing in common...Bigger heavier scopes.

 

Not too surprising weight is an issue. the CEM60 is "spring" or magnetically loaded. And the frequency of a harmonic oscillator (assuming we can simplify to such) is entirely dependent on the spring constant and mass only.  

 

Does makes me wonder... has anyone tried tightening up the tension knobs or something like that?

 

I know its a different mount but same principle of center balance, my cem25p was unable to accommodate a Stellarvue SV102T in carbon fiber total weight about 14 pounds. A simple usb cable with half its weight supported was causing it issues. After troubleshooting what seemed like a overloaded mount i was told the physical length of the scope and the weight all the way at the tail end contributed to my issues? Hello? anyone home? astrophotography usually entails that type of setupbigshock.gif  

 

Well long end heavy refractor is a problem for all mounts. Even so called premium mounts (I use that term because shouldn't precision be a better class? Premium implies it's a luxury) states that their weight limits depends on the moment arm of the OTA.

 

It's also why it's better to put more counter weights on closer to the RA axis than having less but further away. 



#77 rmollise

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Posted 23 February 2018 - 11:25 AM

Reading through most of the reports on here they seem to have 1 thing in common...Bigger heavier scopes.

To some extent. But I believe all I've heard about are well within the payload specs iOptron uses. At any rate, the behavior of these mounts is just not normal no matter what the payload.


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#78 AntMan1

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Posted 23 February 2018 - 06:44 PM

 

Reading through most of the reports on here they seem to have 1 thing in common...Bigger heavier scopes.

To some extent. But I believe all I've heard about are well within the payload specs iOptron uses. At any rate, the behavior of these mounts is just not normal no matter what the payload.

 

I agree with you 100% and I don't believe the quoted weight limits from ioptron.


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