Quote:
Originally Posted by phomer
Stefan,
I recall getting totally lost on this when I needed an adaptor. A glass filter will extend the focus point 1/3 of the filter width further away from the objective or mirror. It effectively extends the focal length, so you would need to increase the adapter length.
Paul
|
Paul,
Thanks for chirping in and please believe me that I'm completely at peace with Snell's law. My problem is purely with the QSI document I posted.