Thanks Andrew for explaining how direct drive works.
Interesting about the new mount. Software Bisque mounts also use a drive belt that runs other gears. The PME 11 can be fitted with encoders but it has to be at the time of ordering.
Here is the link for the Astrophysics encoders with sample images:
http://www.astro-physics.com/index.h...ducts/products
From what little I have heard about it they work. Unguided works on most parts of the sky so I guess that implies you may need to autoguide on the other parts.
I believe it. My AP1600 when going along with an autoguider with PEC at around half an arc sec some of the time ( almost half the time) and at about 1.5 arc seconds briefly. The bulk of the guide graph is around 1 arc sec. Average last time I used it was 1.2 arc secs of error. Without PEC it was about 3.5 arc secs. Much like a good PME.
Greg.