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Message: <blockquote data-quote="OPTIC_NUT" data-source="post: 3285299" data-attributes="member: 121951">There is the 11-degree 7x35 (and similar apparent field for other powers)....very wide filed, but only very sharp for 40-60% of that.  (77 derees apparent)Then "clear semi-wide", usually about 55 degrees to 70 degrees apparent.Sharp to as much as 80% of the field sometimes. Big view, but not slushy."Precision flat narrow":  no rolling ball or pincushion when you scan,sharp edge-to-edge, often 50 degrees apparent to 55 deg. apparent.It seems the best of these have astigmatism at 99% of field, but that'sjust the diffraction of the field edge.  Relaxing to look through.Easy to scan fast. But...limited field, of course.</blockquote>