Hi Folks, I've had a nice 10" RC-style Cass mirror set that has been, in fits and starts, making its way to becoming a telescope. After a long fit, I'm back into the start mode. I've run into some issues that I find I really need help with. If there's someone who'd be willing to spend some time coaching me, I'd be most grateful. If someone has, or knows of a place to do some testing of Cassegrain mirrors that would be extra helpful. One of the main issues I'm struggling with is trying to determine the correct separation of the mirrors. I know that can be determined quite well with a Ronchi test, but I've been unsuccessful in achieving a test setup that even allows me to see the lines. (Part of the difficulty is that the scope is not really fully put together and I'd appreciate some advice on how to proceed from where I am.) At any rate, if anyone has some time or knows of some sources to check into, I'd sure like to hear from you. (I'm located in Orem, and if more convenient, would happily come to you.) John