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Message: <blockquote data-quote="edz" data-source="post: 1265762" data-attributes="member: 44073">When binoculars were tested at boosted power powers, I see considerably wider differences in resolution between models of same power. Once again, generally I bring out one or two used previously to benchmark the current batch.  I have a variety of powers used for boosted testing, but for sake of this list all of these here were tested with a 6.2x booster.  Also once again, about half of all the binoculars actual magnification is not what is stated as nominal. For instance, of the 14 8x40/42s, 5 were greater than 8x and 4 were lower than 8x.  The normal power range in the 8x binocs tested is 8.3x to 7.5x,  so the boosted powers actually range from 46x to 51x.  Of the 12x50s, three are 12.0x, one is 12.2x and one is 12.5x.14 - 8x40/42s ranged from 6.8” to 3.8”, 5 of them 4.8” or less4 -10x42s ranged from 6.1” to 3.6”, 2 of them at 3.6”12 – 10x50s ranged from 6.1” to 3.0”, 6 of them 4.1” or less1 – 10x60 was 4.8”1 – 10x70 was 3.0”2 – 12x50s were 2.7” and 2.56”2 – 15x70s were 3.0” to 2.56”1 - 16x70 was 2.4”FWIW, out of  48 binoculars (16x70 or smaller) that were tested, 10 of them are premium binoculars and another 7 are near premium.   9 more Chinese branded binoculars are among the best measured for resolution.  This represents more than half of all the binoculars tested.  There are some poor quality binoculars in my group, however there are only few in my test group that are really cheap or very poor quality.  Out of all 60+, there are at least nine that I wouldn't recommend to anyone.You can't really assume what maximum apparent resolution you are seeing in my values, because as I stated several times now, the actual magnification of most of these binoculars is not what is stated nominally.  For instance, after multiplied by the real power, the best apparent res in three of my 20x binocs is 86, 87 and 88 arcseconds.  5 out of 7 20x80s tested were less than 20x, two of those being less than 18x.edz</blockquote>

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