Focus Ajustment & Barlows

Hello Guys,

I recently built an 8" f6 telescope and am using a set of Meade series 4000 Super plossls. When I constructed the scope I had prime focus set at a point where the focus tube was sticking out about 1 1/2 inches from my low profile helical focuser. I purchased a Celestron Ultima 2X barlow and when I use it the prime focus occurs with the focus tube barely sticking out above the focuser. It leaves me almost no in-travel. Is there a way to adjust this or do I need to get a different barlow? Any help offered will be greatly appreciated.

Thanks,

You can move the mirror forward on the collimation screws, taking care not to unscrew them too far and thus dropping the mirror. You can also remount the mirror somewhat further forward.

jon