Author Topic: Whither manual EQ mounts? Questions on Chinese-made EQ-5 class mounts and altern  (Read 1831 times)

Bill Godschalk

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I'm an almost exclusively visual observer, who occasionally throws my wife's DSLR in the mix for some quick (~30s) unguided shots, mostly just for fun, but also to bring out details in the faint fuzzies that I don't have enough aperture to see with my own eyes. My current EQ mount is the Orion-branded Synta EQ-3 (i.e. Orion AstroView). I used to hate it, thinking that the 150mm f/5 it came with was woefully undermounted (huge vibrations that take too long to dampen), but once I added the dual-axis motor kit (I got the Celestron version off of Craiglist; probably would have bought the Celestron version new since it's a little cheaper than the Orion one) my perspective on the mount totally changed. It still takes just as long for the vibrations to dampen, but once they do, whatever you're looking at stays dead center in the FOV for as long as you care to look at it. I am now a big fan of the mount, as it's relatively portable and offers decent performance for what I do. The one thing that really bugs me about it is that the RA axis has no clutch, so it isn't an easy matter to switch it to fully manual operation if for some reason I wish to do so.

Call me a luddite, but I don't like the idea of needing power in order to observe. I have no qualms with taking advantage of it when available, but I don't want it to be an absolute prerequisite. Batteries can run down, break, or neglectfully uncharged; any number of things can go wrong with motors and their control systems; I just like the idea of being able to easily fall back to manual. Even when everything is working, I like the idea of being able to center with the manual slo-mo controls, then tighten the clutch and let the RA motor track, and just letting the hand controller sit on the accessory tray and not having any reason to need to pick it up and fiddle with it.

I'm not actively in the market to upgrade my mount, but I know I will eventually, and like to sort of idly think about it from time to time. The obvious upgrade would be one of the many clones of the Vixen GP (or a used Vixen GP, since the Vixen AP just doesn't do it for me), all of which could be fitted with a dual-axis drive system with clutches to allow easy switching to manual slo-mo on *both* axes. But I'd like to know if there are any other decent options out there for manual-capable mounts. It sure doesn't seem like it. I'm guessing that the glut of inexpensive and reasonably capable EQ-5 type mounts makes it difficult for anybody else to justify making engineering the ability to use a mount with fully manual controls for the few of us who want that capability.

The EQ-5 type mounts that I have been able to identify so far are:

Astrozap AZ-3000 (it took me forever to realize "AZ" probably refers to "AstroZap" and not "AZimuth")
Bresser / Explore Scientific EXOS-2
Celestron CG-5 (no longer produced)
Meade LX70
Meade LXD-75 (no longer produced)
Orion SkyView Pro
Sywatcher EQ-5

And of course the original: Vixen Great Polaris and derivatives (no longer produced)

IIUC, these are all based on the Vixen GP design, and should all be reasonably compatible as far as motor options are concerned. They all look completely identical apart from color, with the exception of the SVP, which has more sculpted lines and has the setting circles in a different location. I believe some are made by Synta and some by Jinghua?

Anyway, I guess my actual questions are:

* I'm assuming not all of the above options are created equal, despite looking pretty much identical. For example, even though I've never actually used a Celestron CG-4, I sort of assume that despite it being pretty much identical to my Orion AstroView, the CG-4 would be slightly better just due to the fact that it comes with a more substantial tripod. Also, I hear the original Vixen mounts were made to tighter tolerances than their clones ever were, and I imagine there might be some variability between the currently produced clones as well. Do any of these mounts clearly stand out from their peers?
* I'm assuming I've missed some other, let's call them "GP compatibles". Have I? Which?
* I'm hoping that the "GP compatibles" aren't truly the only option for mounts that are both dual-axis and manual capable, where switching between the two doesn't require a screwdriver. Please tell me there's other possibilities. I'm intrigued by the Losmandy GM-8 and G-11 design, which as I understand uses friction clutches that let you just repoint by hand, but having never actually seen one, I don't have a good idea as to whether it's sensitive and smooth enough to be acceptable for fully manual use when the occasion calls for it. (I would sort of imagine tracking manually by just gently nudging the counterweight shaft to move in RA without moving in DEC, but worry that it would be hard to nudge gently enough to avoid overshooting at high power.) Any thoughts on other EQ mounts that can easily switch between motorized and manual control?