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First of all Michael, that's some nice work, and
it's good to see someone else using 100 and 400F!
As Roland and others have mentioned, the blue
"ghosts" do look puzzling, especially when shooting at f/10. Were you using a
filter? These "ghosts" appear on all your Fuji 100F and 400F shots, and also on
your M17 shot on E200. They really don't look like they are radial in nature,
especially in the M17 shot.
I did some shooting with Sean Walker's C9.25 @f/10
earlier this summer on Fuji 400F, using a Lumicon Newtonian Easy Guider. I did
not see this ghost problem. For an example I just temporarily posted a full 35mm
frame jpg from a 90min shot of M27 (taken with an IDAS filter and
unfortunately somewhat underexposed) at: http://people.ne.mediaone.net/jeboud/temp.htm
There is some blue noticeable to the outside of the
brighter stars towards the edge of the field due to the scope's coma, and a
guest satellite <g>. My focus point was about 1/8 of the field from
center.
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