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Message: <blockquote data-quote="james holdsworth" data-source="post: 3439221" data-attributes="member: 79864">Here is Allbinos explanation about testing ''astigmatism''....ASTIGMATISM (10 points) - We considered a level of astigmatism trying to achieve a perfect punctual image of stars. Then focusing in two different distances we measured the vertical and horizontal deformation in relation to spherical symmetry axis.When they refer to ''perfect point-like stars'', they are referring to central sharpness.This is their version of sharpness testing - it is not testing edge resolution or what we would consider classic astigmatism. This testing showed both samples to be ''sharper'' [if we want to use that term] than several FL's, the HT, Swaro SLC and Habicht.I think, owing to the overwhelming sentiment expressed by owners / users of HD's and professional testing, that you have tested a poor sampling.</blockquote>