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Quote:Hi Guys,Over dinner at this past weekends IAC we were discussing the new paramount and astrophysics mounts that come with optional encoders. More specifically, with protrack and tpoint like models running in software, is there really any benefit to having encoders especially when they can run you many 000's of $$$?I would welcome any thoughts / opinions on this topic.CheersChris
http://www.faintfuzzy.net Stuff C14, C8, Orion XX14i, Meade 8" ACF, AT6RC, AT102ED, Orion ED80, PST, AP1600GTO, CGE, CG5, ST10-XME/CFW8, QHY8PRO, Optec TCF-s, Microtouch Focuser, Pyxis LE, Hyperstar for C8.
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A-P 105 Traveler ~ TEC 140 D ~ TEC 6 MCT ~ XT10 (Zambuto)
A-P Mach1 GTO ~ Losmandy GM-8 ~ TV Gibraltar
Quote:Thanks guys - I imagine the two systems are pretty much the same idea.I agree it means the mount knows (to some accuracy) exactly where it is at all times and can check after a slew that it actually got to where it thought it was going. Clearly periodic errors should be cut significantly - by how much is yet to be seen as PEC is already very good. Would be nice if they inlcude a relay to trigger a park on the ME without the PC - e.g rain detected -> immeadiate park.Chris
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Quote:When I suggested that it knows where it is, I was not referring to it's position relative to the sky. I was talking about it's absolute position mechanically.For example, if you have some issue where the mount ends up losing its sync, you can end up having to go on site to correct the problem (or risk crashing expensive equipment into other expensive equipment).
Others may disagree. Your millage may vary. Void where prohibited by law.
Quote:Quote:When I suggested that it knows where it is, I was not referring to it's position relative to the sky. I was talking about it's absolute position mechanically.For example, if you have some issue where the mount ends up losing its sync, you can end up having to go on site to correct the problem (or risk crashing expensive equipment into other expensive equipment).Absolute encoders will certainly give you that, but so will a homing sensor at far less cost. Paramount mounts since at least the GT-1100S circa 1999 have had homing sensors. With the ME-II they're also offering optional (and quite expensive) absolute encoders.By the way, with absolute encoders there are no positioning ambiguities and therefore no park position restrictions. But I wouldn't buy them just for the benefit alone.
Quote: compensating wind gusts.
Quote:Quote: compensating wind gusts.
The encoders will only correct mount errors they can measure. The encoders can't, for instance, correct pointing errors caused by the OTA vibrating or bending from the wind, because those errors are not "visible" to the encoders.
- Jared Willson