I've come across this interesting article on arvix entitled;
"
Is Magnification Consistent? Why people from amateur astronomers to science's worst enemy have some basic physics wrong, and why."
Written by Christopher M. Graney, who is a physics teacher,it is an informative and interesting paper.
What is it interesting about this paper it discusses how telescopic magnification works and talks on the misconceptions in how telescopes magnify.
I also like the concluding quote;
"The question of correct understanding of the phenomenon of magnification, something that is easily accessible to students and that has practical application to the “real world” of familiar optical devices, has had a real impact beyond just the world of physicists. Misunderstanding this bit of basic science helped produce broad misunderstanding of science in general. Now there’s a story to tell your students when they complain about your insisting they get the details right in your class! After all, you wouldn’t want one of them to someday become the newest “worst enemy of science” based on a misunderstanding of basic physics."
Link;
http://au.arxiv.org/ftp/arxiv/papers/0911/0911.4757.pdf