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LewisM
07-08-2017, 01:29 PM
I have my Astro-Physics Star 12ED mounted on my Sphinx SXW for visual simply due to the excellent visual attributes of the system. It easily handles the weight but the moment arm of the scope is a oroblem in amplifying any vibrations to the point focusing becomes a problem.

The mount is on the standard Vixen HAL 130 tripod with the spreader and triangle tray bolted down. I have put a spare counterweight in the tray which helps a little but still lots of vibration when focusing (it dampens instantly when you take hands off). Plus imaging in any wind will be an issue (it's a long tube, being a 1020 focal length (120mm f/8.5))

Would upgrading to a Berlebach Planet help with moment dampening or is only changing to a stiffer mount help. I have been considering an NEQ6 in the interim but remember the dec head slop in those (fairly simple fix). Maybe an AZ-EQ6 better?

Long term goal is an Mach 1, DDM or an EM200 but in the meantime I need something a little beefier if a tripod upgrade is not going to help (I plan getting the Planet with GP head anyway for use with my GPD and simply use the 60-45 adapter to use the SPHINX On it). I can also use an electronic focuser but prefer not to.

Any ideas?

Wavytone
07-08-2017, 02:16 PM
Hell yes... the planet is vastly stiffer tripod. Steffen had one at Blackheath recently with his mak on it and it was quite superior to both the Losmandy LW and surveyors tripod I currently use. Made me quite envious as I also need a beefy mount for the Russian Tank.

Steffen had asked Berlebach to modify it slightly so that the legs open wider apart - the standard version has the legs fairly close together.

What impressed me most though was the head of the tripod, it was larger than the photos imply and very nicely engineered.

I had a vixen mount before, on the HAL ... not impressed frankly.

xelasnave
07-08-2017, 02:45 PM
If you are changing that's anther matter.
To improve the current mount try more weight.
Consider filling the legs with builders foam maybe...sand??
Alex

Atmos
07-08-2017, 03:02 PM
Matt has said that the dampening time with his modified EQ6 tripled is a lot better after modification so by that theory changing to a Berlebach Planet is a good idea. Not only that but they have interchangeable "heads" which could be helpful.

As for going with a DDM mount, whether I'd recommend one for you greatly depends on what you're wanting to do. For AP I cannot fault it, it's fantastic! I've never used mine for visual but after having been using my DDM60 for about a year now, I'm not sure I'd want to.

To explain. Early on I had a number of issues with imaging. Some nights it would work without a fault, other nights it was a nightmare! Continually throwing up position errors where it would just drop working until I restarted the software.
Eventually figured out that some nights my balance wasn't quite PERFECT so it would throw a hissy fit and just stop working. If I was to add or subract something from the norm on the setup one night I would have to recalibrate the PID parameters for the new weight distribution other wise it would throw up "Position Error" the moment I turned my back.

If every night you have the same setup, same weight distribution, perfectly balance: and get your PID parameters correct for THAT setup, it's a dream to use.
As I said, I haven't used it for a night of vidualto see how it goes but it doesn't seem like a mount for visual applications unless you want to keep the same EP in.

LewisM
07-08-2017, 03:15 PM
Thanks Colin! Something THAT weight sensitive is not something I desire, so I'll give the DDM a pass I guess.

REALLY leaning toward the Mach 1 eventually anyway. I was on A-P's list and my name came up, just at a VERY bad financial time.

I have had 2 Planets before, so knowing how good they are, I'll order a Planet (tall) from T-E tonight with the GP head, double clamps and some other parts whilst at it. Even with post it comes in under $1k direct from T-E rather than the local gouge.

Atmos
07-08-2017, 03:25 PM
For someone purely going down the astrophotography path I would hands down recommend the DDM60. It only takes a couple of minutes to get the balance perfect as it has a cool tool for that but who wants to have to continually rebalance? It is a lot easier to move my HEQ5 around the sky when it is balance even just pretty good but it still tracks regardless and doesn't lose itself ;)

Kunama
07-08-2017, 03:32 PM
I have a spare 'Planet' top sitting here somewhere but it is a flat top plate with a 3/8" hole..... needs some legs which can be ordered separately from TE :D
Would go well with a Vixen pier extension and I know where there is one... ;);)

LewisM
07-08-2017, 05:05 PM
Do you think he'd let me have it? I mean, it's like his TOA and TSA - NEVER used, just gathering dust. You do have the keys to the shed...

Unless you mean YOU have one :)

issdaol
07-08-2017, 05:27 PM
Yes ....A genuine Vixen Pier Extension would significantly improve the setup especially with that FL scope

LewisM
07-08-2017, 05:41 PM
It's not going to increase the vibration damping you doof.

I already swapped to the TALL HAL130 version, and it is TALL when using it, so no desperate need to go up another foot.

issdaol
07-08-2017, 05:44 PM
Not talking about vibration Doofus .......talking clearance :P

LewisM
07-08-2017, 05:52 PM
Are you offering me yours Benito. :)

Greenswale
07-08-2017, 06:25 PM
I have quite a large Berlebach tripod under my Skywatcher 120. Way better than the Vixen Port Mount tripod! Damping is excellent.

BUT! Best reduction in vibration came with installation of an electric focusser. I would try that first.

The Mekon
09-08-2017, 05:16 PM
Not quite on thread Lewis, but I note your signature says Star 120ED quantity made 150. Perhaps this came from the informal AP database that is available on the net. The same database says highest serial number known 42. I have a feeling a lot less than 150 were made of this scope. That same source says 120 of the 130EDT F8 were made. A scope that was available for much longer than the 120.
Any ideas?

LewisM
09-08-2017, 06:06 PM
John,

A-P seems reluctant to tell me, oddly. I am guessing perhaps 42 is correct based on A-P not even adding anything to it on the A-P page. I asked Roland Christen direct - no response, and George skirted the question. Weird!

Needless to say, not many exist.