Visual Resolution 500 Mega Pixels
<p>Apr 21, 2009 9:54 PM
 
excellent estimate:
 
can distinguish a line pair with a separation of 0.59 arc minute.
(he says, one needs two pixels per line pair =  pixel spacing of 0.3 arc minute.
(full moon is 30 arc mins = 0.5 degrees)
 
width of thumb = 2 cm
hold thumb at arm's length (say 1 meter away)  =  1 degree.
 
1 minute of arc = (from wiki on that) abt 2.9 cm at 100 meters  (used by marksmen and gun scope makers)
(say, call it 3 cm at 100 meters)
=  300 microns = 0.3 mm at 1 meter.
= 1 minute of arc;  so one degree at 1 meter = 60 * 300 microns = abt 2 cm = 1 thumb width at 1 meter.
 
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