Can anybody tell me why the focal plane ol the telescope objective lens falls inside of a Huygenian eyepiece?? This phenomenon is apparently unique to this particular eyepiece design but I have not been able to find any explanation of why it happens. As near as I can tell, the design of both Ramsden and Kellner eyepieces are very closely similar but they do not behave in this same way. There must be some fundamental aspect of the design which is responsible, but which I am continually overlooking. I would very much appreciate a solution to this little puzzle.
Thanks in advance,
Dave K.
Thanks in advance,
Dave K.
