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Message: <blockquote data-quote="edz" data-source="post: 1561239" data-attributes="member: 44073">from my other postmore than 10 (out of 60) binoculars ranging from 7x50s to 15x70s that all could see resolution of 3.4 arcseconds down to 2.4 arcseconds. Only one was a roof.here's the same list I posted before only in order and now including a second sample of the ED2 8x43.  all values rounded to nearest tenth.Leica Trinovid 10x42 rp 3.4Celestron Regal 10x42 rp 3.6Zen Ray Summit 10x42 rp 3.8Zen Ray ZEN ED2 8x43 rp smpl 1 4.1Zen Ray ZEN ED2 8x43 rp smpl 2 4.1Celestron Regal 8x42 rp 4.1Oberwerk 12x50 Sport rp 4.3Bushnell Legend 8x42 rp 5.4Garrett DCF 8x42 Apo rp 5.4Nikon Monarch ATB 10x42 rp 5.7Pentax DCF HRII 10x42 rp 6.1 BUT take note:  the second sample of the ED2 8x43 did not reach the same limit of normal power resoluion as sample 1 8x43, the ZRS or the Regal LX, or several others for that matter.  So, as much as people like to look at boosted resolution, you should probably only weight that boosted value about 1/3 weight vs 2/3 the weight given to normal power resolution.  For instance, here's the same list as above only this time showing the actual normal power resolution (times the power to equalize).Zen Ray Summit 10x42 rp 81Celestron Regal 10x42 rp 83Celestron Regal 8x42 rp 83.5Zen Ray ZEN ED2 8x43 rp smpl 1 84.5Bushnell Legend 8x42 rp 84.5Garrett DCF 8x42 Apo rp 86.5Oberwerk 12x50 Sport rp 87Leica Trinovid 10x42 rp 88Zen Ray ZEN ED2 8x43 rp smpl 2 89Pentax DCFHRII 10x42 rp 94 Nikon Monarch ATB10x42 rp 97To get some idea of how these stack up to all binoculars, values around 85 are good, below 82-83 very good.  the best binoculars all range between 75 and 81.  the worst are all over 90.Boosted resolution values do not give a clear indication of normal power resolution and should not be weighted as much in trying to see where things fall in rank.  I don't ignore boosted resolution, I just give normal power twice the weight when trying to fit it all together.  Nothing in the above values is weighted, it is all direct.  I'm not ranking anything here, as that would need to take into consideration a dozen other aspects of performance.  You can take the data and use it however you like.  But it should be pretty obvious, with few exceptions in the data, anyone who uses exclusively boosted resolution as opposed to anyone who uses exclusive normal resolution is going to come up with a much different list order.Also one comment about Zen Ray's "spec" of 3.2 arcsec for a 43mm binocular.It's either coincidence or what Zen Ray does here is calculate the Rayleigh limit of a 43mm lens 138/43 = 4.2arcsec.  This is not a useful value for any daytime observing or for comparing to any values obtained using a "line pairs" chart.I'd recommend following Steve's link above back to his resolution tests where you can read more about what you need to know regarding resolution, But here's the short of it.Can't compare Rayleigh resolution limit and line pairs resolution as equals. Rayleigh limit is measured on point sources against a dark background.  Stars, at night.  Line pairs resolution will always be on the order of about only 60%-70% as wide as Rayleigh.So, if a 43mm lens has a Rayleigh Limit of 4.2 arcseconds, it should have approx a 2.7 arcsec limit of resoluion using a line pairs chart.  All scopes that I've tested at Rayleigh and with line pair charts show this exact relation.  No binoculars that I know of reach the corrected line pairs limit. edz</blockquote>

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