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Message: <blockquote data-quote="spitfiretriple" data-source="post: 1743040" data-attributes="member: 78740">Crikey Kevin, you've been busy.  And you have gathered quite a range of different behaviours.  As you say, this is all quite complicated.  Much more so than I had anticipated when I started experimenting.  I do note four differences between your tests and mine:1.  I kept my binoculars fixed relative to the screen; you turned yours.I don't know what significance this has, if any. I suspect it will affect some observations.  But our two sets of tests were at least internally consistent.  It's probably valuable to come at the challenge from different perspectives, using different methods.  As long as we don't let this confuse us.2.  You used linear-polarised sunglasses; I used (I understand) more complex Avatar glasses (they were all I had available), with a circular filter and a linear filter - leading among other things to their performing differently when reversed.3.  You didn't try reversing your glasses - but then this would have achieved nothing, see point 2.4.  Your glasses had a brown tint, that will have affected colour perception. My Avatar glasses were more neutral.  Note: I'm not criticising, we can do these experiments only with the materials we have available.Your results and mine seem to combine to suggest that there is not so much an absolute difference between the phase-corrected and the non-phase-corrected; it is perhaps more useful to observe that even when phase coating is present, its effect varies widely with its type and quality.</blockquote>

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