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Vixen Porta II - suitable for a reflector?

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#1 osbourne one-nil

osbourne one-nil

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Posted 07 May 2013 - 08:19 AM

I didn't have long last night, but once it eventually got dark, and once Saturn eventually climbed high enough to have a decent view from my back garden, my son and I had a lovely hour or so just watching it drift through the field of view with my TV85. I love the simplicity and stability of the mount and the slow motion controls work really well. The only thing lacking was a bit of oomph, with the TV 85 only being 700mm focal length.

I've been wondering, therefore, whether the mount would be suitable for something like an f8 (1200mm) 6" Newtonian? I know the weight wouldn't be an issue (the mount is rated at 20lbs) but would the length of the tube make it very difficult to point upwards, and to reach the eyepiece without bumping into the tripod legs?

I know I could go down the route of the SCT or a Mak, but I like reflectors, as they're like me - a bit simple.

#2 RTLR 12

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Posted 07 May 2013 - 08:49 AM

The weight limit of 20# is way too optimistic for the Porta II mount. I would limit the mount to about half of that rating. Even at half the weight, the weak point of the porta II is the tripod. Very unstable even under the lightest of loads. An upgraded tripod version would be well worth the extra money.

Stan

#3 osbourne one-nil

osbourne one-nil

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Posted 07 May 2013 - 08:55 AM

Thanks Stan,

My TV85 once kitted with an eyepiece is probably pushing it to its limit then.

I never have long in the evenings you see, and at this time of year, it doesn't really get truly dark, so I just want something quick and easy. My head's telling me to go for a Nexstar 6SE, but I just like reflectors!

Orion Optics (UK) do a long focal length 6" reflector which weighs in at 5kg (11lbs) but it's going to hit the legs I think.






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