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UniStar questions

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#1 m00nless

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Posted 22 August 2012 - 12:23 PM

Does the UniStar have sufficient tension to secure a long optical tube pointing to a high altitude and at the same time allow for smooth movement of the optical tube without having to adjust tension again? Is it necessary to adjust tension or re-balance an optical tube when switching between eyepieces of different weight?

#2 Kfrank

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Posted 22 August 2012 - 12:59 PM

With all the UA mounts, scope balance is a critical parameter. If the tube is not properly balanced, the tension on the alt axis may need to be set higher which may affect smoothness of operation.

I found that having the balance set slightly nose heavy worked best - however, adding a barlow or changing EPs can (and will) change the balance point.

Once I switched to a mount with slo-mo controls, I was much happier.

#3 m00nless

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Posted 22 August 2012 - 02:00 PM

Once I switched to a mount with slo-mo controls, I was much happier.


Which mount with slow motion controls did you switch to?

#4 Kfrank

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Posted 23 August 2012 - 10:32 AM

Once I switched to a mount with slo-mo controls, I was much happier.


Which mount with slow motion controls did you switch to?


Stellarvue MG2.

#5 Rich V.

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Posted 23 August 2012 - 07:43 PM

I agree with Ken; balance is critical because it's important to keep the tension low for the smoothest motions.

For me, with a 130mm f7 refractor, I've found it best to use roughly similar sized eyepieces. I can switch from Pentax to Ethos without re-balancing but going from a N3-6 zoom to a 21 Ethos is too extreme and a re-balance is necessary.

I like the simplicity of the Unistar; it doesn't require an extension and there's no clearance problems between scope and tripod. As long as I have a D style dovetail bar that's long enough to provide at least 3" of fore/aft movement I'm OK. It only takes about 5 seconds to slip the dovetail bar one way or the other in the clamping jaws so IMO, it's no big deal. I can track just fine at the scope's limit of ~300x so the added complexity of slo-mo isn't a feature I feel I need.

Rich






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