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Claire Brown wrote:

> Just to clarify we see this difference in focal plane when we are 
> looking in the scope by eye and not via the confocal scanner. We have 
> also verified that we don’t see it with our other objectives so I’m 
> thinking now that there may be an issue with our 63x objective.

Check for a dirty objective.  I think I've seen junk on the glass 
introduce chromatic aberration.

Good luck!

Martin
-- 
Martin Wessendorf, Ph.D.                   office: (612) 626-0145
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