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Orion SVP Mount
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Orion’s SVP Mount:
A brief shake-down cruise
Sometime last year I acquired Orion Telescope’s “SVP” mount for use with an older, 6-inch “long-tube” Newtonian named “LadyScope”, and have been quite pleased with it for that application. However, while in their Watsonville store for that purchase, the fact that they had several different scopes riding on SVP mounts did NOT escape my notice. In particular, they offer their re-badged Celestron 9-1/4” SCT thereon. Hmmmmm… this planted a bug in my mind that has refused to stop squirming ever since.
For nearly a decade my primary scope has been a Meade 10” LX-50 SCT, which has been upgraded with their “Magellan” push-to locator, had its focuser “Petersonized”, plus numerous other tweaks & tinkerings. As such, it has performed superbly as a “visual” instrument, giving me countless hours enjoying the heavens! Typical of Meade’s SCTs, it is rock-solid, & has been a fearless performer at star-parties for young and old; If you’re 8 years old & at a star-party goofing around in the dark, when you whack into this beast it will be YOU who is the worse for the encounter! But that rock-solidity comes at a price… WEIGHT!
The tube & fork assembly which must be lifted from its storage cabinet (or car trunk), waltzed thru doors & across the yard/field, hoisted up to tripod height, & gingerly set onto its wedge weighs about 65 pounds. For a younger buck, this presented no problem at all. Yet younger bucks have backs that gradually grow older… and while I can still do the LX-50 waltz without missing a beat, I’m just beginning to wonder “for how much longer?”… and what price will be paid when I find that I have “missed a beat?” A broken scope? Worse?... i know too many folks with back problems, and I’d just as soon NOT join their ranks at this stage of my life!
Okay… enough whining about hefty telescopes! What can be done about it?
Well, I’m glad you’ve asked! I’ve learned that Orion’s
9-1/4” SCT OTA weighs about 20 pounds, which is kid-stuff! … and
which, coincidentally, is the load capacity they rate their SVP mount for. The
question is, how effectively does that SCT ride on that mount? I mean, really-
how “pushed” is that configuration for weight & stability? And
so the bug squirms…
The Phone Call…
Finally bugged to distraction, I used some vacation time around the Holidays to investigate these issues. A phone call to Orion yielded some pleasant results: I thought I might be asking a bit- to bring MY binoviewer & accoutrements to attach to THEIR scope on the showroom floor and test focus range & shake factors. They quite gleefully agreed to such tests, even at any time of my choosing! I suspected they might be confident of their product… that they stand behind them as well as anyone in the business is pretty much indisputable; Still, I very much appreciated their cheeriness at my proposal!
Arriving unannounced, I introduced myself to the young fellow at the counter. William was his name, & he quickly hopped to work- moving scopes & repositioning a 9-1/4” SCT/SVP rig to where we could play, err, run some tests with it. Needing a 2” visual-back & star diagonal for my Denk to attach, he called to the warehouse for the parts to be brought forward. (Keep in mind- he knew no sale was to occur, only “testing”) He informed me that, while their current VB has only two set-screws, they are in the process of developing an upscale line of “compression-ring” accessories. This is good news, as the set-screw VB was straining to hold their diagonal when the Denk, loaded with 24mm Pans was supported therein! I didn’t want their retail stuff getting nasty scratches should the assembly suddenly twist, nor was I fond of the thought of MY gear slipping out & doing a bee-line for the floor! Fortunately, for those who need them NOW, TeleVue & Astro-Physics both have 2” SCT visual-backs with very hardy compression-fittings.
With the tail-end load of the binoviewer, the SCT’s dovetail needed to be slid forward almost to the end of its available travel, but this placed the BV nearer to the declination axis and so possibly reduced some of the gyrational jiggles. In any event, it was well placed for the viewer, and was a nice change from using my scope’s sliding weight assembly. The Denk was able to achieve focus with the three sets of eyepieces (EPs) used, from the low-power “StarSweeper” mode all the up to the 2x “multiplier” mode; This is a good thing! However, when in 2x mode the mount’s stability was severely tasked; For the 24mm Pans this would be ~196x magnification… for the 12.5mm Ploessls ~376x! The vibrations resulting from a firm rap to the tube took over 4 seconds to settle beyond annoyance- even a gust of breeze blowing thru the open showroom door caused subtle oscillations. And there was a noticeable harmonic to the vibrations, as the scope assembly’s non-symmetrical weight distribution worked its way out… wiggle-wobble, wiggle-wobble, wiggle-wobble. At 196x this was less than ideal… at 376x it was a little disconcerting.
But as disheartening as this may sound, there IS another chapter to the story! I had brought along my old Celestron anti-vibe pads… seems everyone carries some variant of these nowadays, and I’d guess they are more-or-less equivalent. How I’ve managed to keep this set for so many years without losing one completely escapes me. Once these little beauties were placed under each of the SVP’s pointy rubber feet, the 376x rap-test was re-evaluated. Amazingly, vibe-dampening times were cut to just a nudge over 2 seconds, & breezes had much less influence, if any… these levels I would consider tolerable for my own visual use. Others may not find them so, & I suspect astrophotography would be even more demanding. If you have recently purchased an SVP mount (or any other, for that matter) & are not completely satisfied with its steadiness, you owe it to yourself to try a set of anti-vibration (or, “vibration-suppression”) pads! They’re typically less than $50 for a pack of three.
Certainly the 9-1/4” SCT/SVP rig is not quite on a par with the 10-inch fork-mounted Meade rig in the stability department, for ITS vibration dampening times are normally less than 2 seconds, and around 1 second with the vibe pads in place! Nor would anyone likely be tempted to name such a rig “Punisher”, or “Beast”. However, some folks may be less worried about what their scope will be named, and MORE worried about what their chiropractor may name THEM! “Broke” comes to mind. For these folks, visual observers- among whom I tentatively include myself- this 9-1/4” SCT/SVP scope configuration (with the vibe-pads!) may be a workable solution… and certainly the 8” SCT would be moreso. If I DO end up making the transition from the “Beast” to the 9-1/4”, I will certainly follow thru with further tests & impressions. I might even go wild & try filling the SVP’s steel legs with spray-in Styrofoam, or some such light-weight dampening material.
Finally, I’ll include a few random observations & tidbits. The current SVP mount is equipped with 1-3/4” chrome steel legs. This is contrasted with the 2” steel legs on Celestron’s sister mount, the “CG-5”. This Celestron rates at 35 pounds capacity. Hmmmm. Really? I wonder what else about these might be different… I haven’t seen one, so I can’t really say. Perhaps “sister” is not the correct term?
Additionally, the “Intelliscope” DSC add-on for Orion’s SVP mount is still getting its bugs ironed out, as they’re also doing a fair bit of squirming. My young friend’s guestimate from his time spent with the R&D crowd was for the end of January. Once debugged & available, $200 and a little tinkering with encoders will get you a “push-to” upgrade for your SVP mount. Of course, it won’t be contained in a tidy handpaddle package with the directional controls, or functional as a “Go-To” like that from the “Big Two”… but that’s what Velcro & ductape were created for! But seriously, if one were looking for a NEW mount to begin with, they’d be silly to pass-up at least looking at the CGTs & LXDs wherein you get the fully integrated package and performance. This info is aimed more at those of us content to tough-it-out with the simplicity of our SVPs… and for me specifically, the allure of using multiple scopes on the one mount!
Orion Telescopes appears to be slowly upgrading their equipment offerings, with compression fittings, Crayford focusers, & DSCs, soon (hopefully) joining the green lasers & TeleVue EPs in embellishing their expanding line of CATs, ED refractors, & beefy EQ mounts. How long can it be before they’re also offering a fully Go-To SVP variant? ‘Tis a good time to be an astro-consumer! Still, for some of us consumers, a little careful investigation goes a long way toward exterminating the bugs from our conscience… or at least reducing their squirm factor!