That's partly why I recommend Optec Sagitta OAG for reasons I described earlier.
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— The OAG they recommend is OAG-M which has an opening smaller than 52mm. The prism will definitely shade incoming rays of light.
They also sell an OAG-L which unfortunately has no adapters to adapt to the filter wheel CFW3-L. So strangely their CFW3L is not compatible with their OAGL as you would expect but instead is compatible with their OAGM.
And their OAGM is really too small for the QHY600 chip.
it’s bad naming and rather poor design.
A solution to the shading problem is to build a custom adapter from OAG-L to CFW3L. The adapter is non trivial however not difficult to build to build properly for various reasons I won’t go into unless someone asks. Precise parts won’t do it as it is a non threaded adapter (too fine threads , too little thread engagement)