A CAT setup on a wedge needs to be polar aligned, just like a GEM. Some fork-mount CAT OTAs have finders with polar alignment reticles that can provide a semiaccurate alignment, but most wedge users just do a drift alignment as described in Chapter 11. The only reason to put a fork on a wedge is for imaging, and a drift alignment is almost always required for imaging quality tracking, whether a finder of this type is available or not. A "polar finder" can shorten drift time, however.
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