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What's the biggest scope for the Portamount?

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#1 Darren B

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Posted 12 April 2011 - 12:10 AM

What the biggest scope a Portamount can handle?
I have sorted out the tripod issues with my Portamount and upgraded to the HAL SX130.
The scope I was thinking about a 6 inck Maksutov weighing around 6kg/ 12Lbs OTA only.

#2 RTLR 12

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Posted 12 April 2011 - 02:56 AM

Darren,

I have a PortaII mount and mount my SV115T on it. With the original tripod it's a little shakey so I use the tripod from my CG-5 and this makes for a more sturdy platform. I'm using a 2" diag. and EPs so the configuration weighs in at about 15#. I was getting some flexure in the alt and azm axis, but I tightened them up a bit and this solved the problem. I'm fairly confident with the Porta II now and I do enjoy it's ease of set up and portability.

Stan

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#3 Darren B

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Posted 12 April 2011 - 02:40 PM

That telescope does look quite substantial on that mount. The heaviest I had on mine is 9lbs, it handled that easily.

#4 Don Trinko

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Posted 12 April 2011 - 02:50 PM

I think 12 lbs is a little to much. I'm not sure what they officially say but I think it's 10 lbs.
If you want to look at higher magnifications it's better to go under the rating. All IMO; Don T.

#5 wz2

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Posted 12 April 2011 - 05:32 PM

The Portascope, of course :)

#6 RTLR 12

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Posted 12 April 2011 - 05:48 PM

Load capacity listed in the book that came with my Porta II is 15lbs. Load capacity for the Mini Porta is 10lbs.

Stan

#7 Don Trinko

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Posted 12 April 2011 - 07:06 PM

I have the AT voyager and the Vixen mini porta. I would not put 10lbs on the miniporta! All IMO; Don T.

#8 Jon Isaacs

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Posted 12 April 2011 - 07:27 PM

Darren,

I have a PortaII mount and mount my SV115T on it. With the original tripod it's a little shakey so I use the tripod from my CG-5 and this makes for a more sturdy platform. I'm using a 2" diag. and EPs so the configuration weighs in at about 15#. I was getting some flexure in the alt and azm axis, but I tightened them up a bit and this solved the problem. I'm fairly confident with the Porta II now and I do enjoy it's ease of set up and portability.

Stan


I think scopes like this are about the limit but they do require a tripod upgrade. I have my NP-101 on a Portamount, it's a couple of pounds lighter than the 115 and probably a couple of inches shorter. I am using the Hands on Optics wooden legs but I think the CG-5 ASGT tripod would be even better.

jon

#9 TONGKW

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Posted 13 April 2011 - 03:01 AM

In my experience, a 6” Maksutov of 13 lb would be a bit too much for a Porta AltAz mount and a C6 is about the maximum. I think a Voyager would be better. Also because of the construction of the Porta, the finderscope is placed on the lower left which is not convenient for me.

K W TONG
C8+CG5 GT, TSA102+HEQ5 PRO, MK67+Voyager, NexStar 6SE, C5+Mizar K, WO ZS80FD+Kenko NES, Megrez 72FD+Kenko KDS, Mini Borg 50, PST

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#10 RTLR 12

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Posted 13 April 2011 - 04:52 AM

Tong,
One of these brackets will help with the orientation of your finder scope.

http://www.cloudynig...5/o/all/fpart/1

Stan

#11 TONGKW

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Posted 13 April 2011 - 09:41 AM

Dear Stan,
Thanks for your suggestion. I have seen these brackets.
I have in stead chosen to dispose of the long arm of my Porta mount altogether and substitute with a custom made short arm and this work out very well for mounting my C6. I can revert to the long arm when I want to mount a refractor.

K W TONG
C8+CG5 GT, TSA102+HEQ5 PRO, MK67+Voyager, NexStar 6SE, C5+Mizar K, WO ZS80FD+Kenko NES, Megrez 72FD+Kenko KDS, Mini Borg 50, PST

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#12 Don Trinko

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Posted 13 April 2011 - 10:11 AM

The Voyager has a top bracket that can be put in 3 different positions. This makes it a little more flexible for finder scope possition. Don T.

#13 Doug76

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Posted 13 April 2011 - 11:17 AM

I've had up to an 8" SCT on my PM. A little shaky while focusing, but not too bad. A 6" SCT definitely worked better.
As for longer scopes, I was able to successfully mount a 6" f/5 reflector on it with good results, but also a little shaky when focusing.
In long refractors, I found the PM will handle any 60mm, all the way up to f/20, but it had problems with an 80mm f/11.4.
With the PM, it's not just about weight, although I've found 12lbs is about it's limit. It's also about the length of the scope. So if the scope is short, it handles weight better, and if the scope is long, the weight must be rather light.

#14 orlyandico

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Posted 13 April 2011 - 11:23 AM

someone i know has a C8 on his porta mount.. but i found even his 127mm mak a bit on the shaky side.

#15 cavefrog

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Posted 13 April 2011 - 11:54 AM

I use a celestron 100ED on mine. it is almost necessary to use my damping pads and/or Oberwerk wood tripod though. but it does work well in this configuration.
I have also added a large piece of angle aluminum between the mount and the saddle to bring the scope into a more comfortable position.

#16 Darren B

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Posted 13 April 2011 - 01:11 PM

Thanks, some interesting replies there.

#17 ottovonrotton

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Posted 13 April 2011 - 02:27 PM

I have a C8 I use with an AT Voyager on a Oberwerk tripod and even a 127/1200mm refractor, You must ditch the tripod for something better to get the most (weight) from the mount.

#18 Darren B

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Posted 13 April 2011 - 02:44 PM

Ditched the original tripod long ago. I've got so it settles down less than a second at x225 mag.

#19 BKBrown

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Posted 13 April 2011 - 07:04 PM

The most I have used at one time is a SW100ED with a WO66SD Zenithstar and an Antares RACI finder on board, say 13-14 pounds...seemed to work just fine.

Clear Skies,
BrianB

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