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Message: <blockquote data-quote="Tobias Mennle" data-source="post: 3184992" data-attributes="member: 117315"><p>Brock, as far as I understand Holger´s distortion parameter k means a constant distortion and surely is fine and valuable for theoretical analysis as well as for test series with people and their reactions to distortion. But what I see in the Swarovisions 8x32 and 8.5x42 is not a constant distortion. And I bet I will not see constant distortion in the Zeiss SF either. In the Swarovisions I know it´s slight pincushion for most of the field and then seems to change to less pincushion/different distortion in the "Absam zone" (did you coin the term "Absam ring" by the way <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite2" alt=";)" title="Wink    ;)" loading="lazy" data-shortname=";)" /> ). I also think what we see is not a classic RB/RG by too little general/constant pincushion, but the strange distortion effects when structures move from the outer field over the Absam zone to the image center (or vice versa). The 8x32 really had this "ring" with a sudden change in MTF and distortion which to me was very weird. The 8.5x42 doesn´t have an Absam ring, but a zone with slightly reduced MTF. Very clever flat field implementation IMO. The 8x32 may have been changed since, as discussed above. Agreed, the SE 8x32 which I used 1.5 years was perfect in this respect, but with a somewhat narrow field of view, and with all respect, shame on Nikon for not bringing the SE up to their competitors´ standards...</p></blockquote><p></p>

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