开云体育

Just information here guys. I have a 22" UC, and I have an 11" Celestron RASA, I have a Bahtinov mask that I purchased specifically for use on the 11" RASA,

it has a hole in the middle of it similar in size to the RASA central obstruction.?

When I need to confirm focus on my 22" UC, I simply balance the 11" mask on the secondary cage of the 22" UC and it seems to work just as if it were a full aperture mask for focusing.

It can hang there kind of sideways, or crooked, and it does not seem to make a difference.

I am considering cutting 3 notches in the central hole of the mask just to make it center up better with the three bars that support the secondary on the 22".

My conclusions after trying this are:?

(1) the Bahtinov mask does not necessarily have to be perfectly centered to do its job well

(2) the mask does not necessarily have to cover the full aperture to do its job well

(3) when using it, most of the time I find out that it just "Confirms" that I have already achieved the best focus by eye!, and I have wasted my time dragging out the mask, but I "feel" much better.

So for what it is worth, there you go, hope this info helps somebody.