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Synthetic Stars



I spent the day making a box of synthetic stars.  I got tired drilling
little holes, and I don't have the right tools so they are not very even.
It is just a box painted white inside with a little light and a black
outside,white inside, metal cover with the holes drilled in it. The
attached fits file has been cut down to the bare minimum so as to not use
up bandwith to Tahiti, don't ask me why.   The holes are drilled on a
0.125" grid.  The average position should be fair, but I don't have the
proper set up to make the drill land exactly on the right spot if my cheap
milling machine would get it there.  

OK, this is just a few pixels cut out of a 2k x 2k file.  I notice that the
fits header tell the history of how it was cut from the large file.  Just
be aware that it was in no special place in the image.  Away from the
edges, etc..  It is looking at an array of 7 x 7 #60 drill holes at 23
feet.   A #60 drill ia about 1 mm.  The lens is 135mm focal length.  The
pixels are 15 microns.  

.040/(23x12)=1.44 e-4 radian.  This is 30" of arc.  So the holes are 30" of
arc wide.   15/135000 = 1.11 e-4 radian.  This is 23 " of arc.  So the
holes are 1.3 pixels wide.  

Experts please take a look, and tell me if you see anything you don't like.
 No flat or dark field adjustments, this is just raw data.  With some pain
I could put on a short focal length lens (the pain is in finding a focus -
takes the better part of a day) which would make the spots 1/2 pixel or so
wide.    

Tom Droege

Spots.fts