Hi Kevin,
Thought you might like to see the same field through an f6 Stellarvue 70 ED(420mm FL) and Canon 60Da.
Obviously comparing apples and oranges, but the interesting feature I find is the rainbow which is quite pronounced in my image, even though there is very little colour error. There is some voilet halo evident but that is more due to my poor focus(the focuser is fubar, ruined by previous owner)
I think the rainbow is more an internal reflection problem rather than the lens. I am only guessing tho. I will eventually get some Protostar flocking in there to see if it makes a change.
I've made it to the same scale so you can do a side-by-side comparison. Please try to ignore the trailing
Kevin I would not worry at all about this problem ,,,,
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You might have a point there Laurie , as it seems to much of a coincidence that 2 of the last 3 of these were woefully sub standard , yours and Kevins , when mine was quite good and as said its bad that the lenses are so bad when the build quakity is really very good ? . 
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Its such a shame the optics are not up to scratch in your scope Kevin ( and Laurie's ) when you look at this photo I just found of the LP90 that I had , to see the build quality , baffeling and coatings in this photo and this scope performed very well , this is a real shame .
