I agree..... I've used an STV with two different AP1200GTO mounts and have never used PemPro, etc. I now use the Remote Guide Head with an SBIG STL-11000 with a 1200GTO and still don't use PemPro. I've used both with the efinder to guide imaging focal lengths up to 1200mm with perfect results. When doing film imaging I often did exposures up to an hour long and now, with CCD, routinely do 30 minute sub exposures with perfectly round stars.
Hi Kent,
Of course you can get round stars without PEC even being enabled when autoguiding. However, you may be losing a couple tenths in stellar FWHM (i.e. your images would be a tad sharper).
