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The "new improved" Portaballs 8", 12.5" & 18" - any owners?

reflector
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#51 peleuba

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Posted 29 July 2019 - 11:51 AM

A PB 10" would be cool. 

 

Actually, and this is only my opinion...    but, I think the PB10 is the odd one in the line up.   It uses the same sphere as the PB8 so you have more thermal mass with a 10" mirror to try and cool in a sphere where air flow is now at a premium - bigger mirror takes up more space so air flow is affected.  And, the scope uses the same diameter truss poles as the PB8 but they are something like 6" longer.  This might add up to a slightly shakier viewing experience.  To me, the the PB10 has always been a compromise - not the Goldilocks aperture - between the 8 and the 12.5.


Edited by peleuba, 29 July 2019 - 12:31 PM.

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#52 25585

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Posted 30 July 2019 - 08:17 AM

Actually, and this is only my opinion...    but, I think the PB10 is the odd one in the line up.   It uses the same sphere as the PB8 so you have more thermal mass with a 10" mirror to try and cool in a sphere where air flow is now at a premium - bigger mirror takes up more space so air flow is affected.  And, the scope uses the same diameter truss poles as the PB8 but they are something like 6" longer.  This might add up to a slightly shakier viewing experience.  To me, the the PB10 has always been a compromise - not the Goldilocks aperture - between the 8 and the 12.5.

Better to use the 12.5 sphere, I agree.



#53 mkothe

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Posted 30 July 2019 - 09:28 PM

Gary - I am happy to help. I have owned both an F/6 and F/5.5. PB-8's and a 12.5. I don't require DSC's and my current PB8 is my fav telescope.

One of my favorite features of my older Portaball is how the UTA nestles perfectly in the sphere when disassembled. I can’t visualize how that might work with the new design. Also, the shroud looks very loose in the photos I’ve seen. Is that impression correct?

Michael

Edit: I looked at the website again and the pictures there have a UTA that should fit, but the models from the NEAF picture that was posted earlier are different (just a thin machined ring). Which is the current version?

Edited by mkothe, 30 July 2019 - 09:33 PM.



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