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Why does guiding require near-perfect alignment?
Hopefully there's a simple answer to this, but... Why does a guided mount require anything beyond vaguely good polar alignment?
If the guidescope is constantly sending movement data that the mount is compensating for, and if the mount is capable of moving in any direction at high speed, then what's the damn problem?? I can understand field rotation being an issue beyond a certain degree of bad alignment, and I understand that bad alignment will make the mount's database useless, and I understand that there's potential for (very very small) issues if the imaging OTA and guidescope aren't well aligned with one another... but all those things should make no noticeable difference as far as 2-3 min subs are concerned.
People constantly say that guiding can't correct bad polar alignment. Well, why not?? I don't get it!!
Clearly I'm missing something. There has to be a reason, likely a very obvious reason, that I've overlooked. I'd love to know what it is. Something fundamental about the design of the mount and the speeds they move?
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