G'Day Gary,
Thanks for your detailed reply. Much appreciated. I will follow up all of your points to the best of my abilities. The scope is almost , very almost, finished.
The ArgoNavis I have come with two encoders which I'm not sure about. They only have a number on them: one 8192 and the other 4096. The latter has a small footprint. So what is their true resolution? I've read somewhere that you multiply that number by four to get the true resolution. Is it true? Anyhow I will follow up with the links you gave me and go from there. I've joined the ArgoNavis forum already and I'm learning a lot.
Thanks again, cheers,
John