File talk:Maksutov spot cassegrain.png
Latest comment: 15 years ago by 83.104.249.240 in topic Blue and green lines?
Blue and green lines? edit
What do the blue and green lines signify? Clearly they are light rays but rays from an astronomical object are taken to be parallel, so why both blue and green? 83.104.249.240 (talk) 04:12, 25 February 2009 (UTC)