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Message: <blockquote data-quote="elkcub" data-source="post: 412058" data-attributes="member: 14473">Henry, I agree with all that you've said, but would present my understanding from a slightly different perspective.  Even though Bawko refers to the resolution of the binoculars, in your (our) framework he really means the aided acuity obtained by using the binoculars.  In other words, it's the combined effect of the optics plus the eye he's considering, and that is very reasonable IMO.  (It's the same approach Steve Ingraham uses with his NEED measure, incidentally.)  In effect, if a binocular does all we hope it will do, unaided acuity should be boosted by the magnification and not compromised by the glass that stands between the observer and what is observed. To the extent the instrument does not accomplish this, it falls short of the mark and is therefore inferior to that extent.   With this way of looking at it, I have attached a chart that shows Bawko's binoculars sorted by their ability to aid acuity.  His measurements are simply multiplied by the binoculars' power, and the H and V results averaged.  The AVG column, therefore, is an estimate of his aided acuity with each instrument.  When the results are sorted, I think the ordering makes sense for these binoculars.  I suspect that the results for the scopes may have been influenced by the chart's limits of resolution.  Having said this, I would certainly reinforce your point that the control of lighting and pupil diameter are essential for this method to work.  If they were, however, I'm at a loss to explain why the Nikon pocket binoculars came out first, but then I've got a 10x25 SLC that often puts larger binocs to shame.  <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite2" alt=";)" title="Wink    ;)" loading="lazy" data-shortname=";)" />  Seriously, note that the V arcsec measurement made the critical difference, and this may have been simply due to moment to moment variations in Bawko's acuity.  Again, we have no record of measurement variance, which in my opinion is a potential "gotcha" for any method.  Regards,-elkcub</blockquote>

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