>I guess that
>"thermal expansion/contraction in the microscope stand itself" may give rise
>to quite SLOW variations whereas our previous variations in focus were quite
>FAST. We had regular variation in seconds (like 10s or so).

Yes, you're absolutely right.

BTW, Zeiss sells a heated stage which produces a slightly oscillating
focus when it is connected to output number 1 of the controller although
the temp display is rock solid. Interestingly, when you connect it to
output number 2, which is actually meant for an auxiliary heating plate,
it is stable. When I finally found out about that (after 3 month of
trying everything else) I first thought that my controller was kaputt.
But the replacement I got showed exactly the same behaviour.
Leica also sold as an oscillating heated stage (made by Minitueb) which
we had to return.

To cut a long story short: If you have an oscillating focus, check your
heated stage first.

just my $0.03    (there's inflation everywhere ;-)

blu


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Dr. Beat Ludin, FMI, PO Box 2543, 4002 Basel, Switzerland
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