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Message: <blockquote data-quote="twest820" data-source="post: 3380755" data-attributes="member: 65706">It's an order of magnitude larger than any CA fringe I've ever seen, even in chromatic (i.e. not particularly intended to be achromat) optics, and many times wider than the yellow fringing the 8x32 TEDs sometimes exhibit on dark objects at larger angles from the sun.  More like a second pupil develops that's somehow an optical inverse in the sense a dark area gets duplicated as a bright area.  Though it might perhaps be better to term it revealing glare as opposed to veiling glare as dark areas are accurately reconstructed in yellow.  Unfortunately conditions haven't been such it's occurred when I've been equipped to try to digiscope the TEDs.As the colour and object attachment are similar it's plausible the same essential mechanism could produce both behaviours.  However, CA in the sense I've encountered the term is isotropic (fringing can occur along all sides of an object) whereas this effect seems to occur only in the upwards direction.  It doesn't seem to shift in position as binocular orientation changes in respect to the sun, so could be down to an incompletely absorbed internal reflection from a Schimdt-Pechan surface or something similar.</blockquote>