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Message: <blockquote data-quote="Binastro" data-source="post: 3500262" data-attributes="member: 111403">This morning I tried to repeat the Trapezium observation but it was cloudy.The observation that I recorded in my observing book was 2016 Dec 22 02.14 UT.There is a small sketch showing 4 Trapezium stars, which surprised me. The sketch was made at the time of the observation, i.e. immediately after the observation.The circumstances were unusual.I had rested  for 2 hours in a dark room with faint illumination from the hall.My eyes were very rested as was I generally.The Canon 10x42 L was on the table and I saw that Orion looked good despite extreme light pollution..The whole star test was done in about 3 minutes.The belt stars were very fine.The small cluster stars well above the trapezium were beautiful point like stars.The Trapezium looked like a miniature version of the Trapezium I see with larger scopes.I think my eyes were stopped to about 2.5mm and I was effectively using a top quality 10x25 f/7 binocular.The binocular was tripod steady.I don't wear glasses with binoculars.I have little astigmatism.I do see stars considerably fainter than many observers.When completely rested my eyes are probably 20/15 or slightly better.I do see the 7.6 mag star between Mizar and Alcor with old 10x25 non phase coated binocular in severe light pollution. Hand held, braced but not stabilised or tripod mounted.I have  seen Titan, mag 8.4 with bright Saturn in the field with a telescope stopped to less than 20mm, magnification about 30x.To see the closest separation double stars it is essential to be able to vary the exit pupil to the optimum size.In addition a variable density filter is needed for the optimum illumination level observation.These conditions sometimes occur randomly.I frequently use variable thin cloud as the variable density filter.I think that the daytime double artificial star test was measured at something like 65 arcseconds with better eyes than I have. At least better resolution, but maybe not as light sensitive eyes as mine.</blockquote>

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