On Jun 1, 2015, at 12:15 AM, Duke stereospace(-at-)gmail.com [anaglyphs] <anaglyphs(-at-)yahoogroups.com> wrote:

An experiment using my Celestron C5 500mm mirror lens on my Canon Rebel t3i.&n bsp; The yellow rectangle in the first shot shows the coverage of the lens at that camera position (equivalent to an 800mm lens on a full-frame sensor).  The second shot was a cha-cha with about a 12~15-inch base.  The deviation was more than I expected, hence the window violations on the traffic signals.  I will not be using this lens much, anyway, it simply is not sharp.  

Duke