Good examples in "Putting lenses to work" by John Weigley: https://youtube.com/watch?v=QZy4Yml3LTY https://youtube.com/watch?v=QZy4Yml3LTY Then for a great bo

Good examples in "Putting lenses to work" by John Weigley: https://youtube.com/watch?v=QZy4Yml3LTY https://youtube.com/watch?v=QZy4Yml3LTY Then for a great book that gives a great understanding see Chris Penner's amazing and fun "Optics by example: https://leanpub.com/optics-by-example https://leanpub.com/optics-by-example