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Quoting Robert Zucker <[log in to unmask]>:


 > How is this occurring?  Why is the system going out of
> > calibration? Must we test at multiple times in the day to
> > insure a calibrated system? How would you test for laser or
> > machine drift on your confocal machine?

The Leica TCS2 spectrometer is a delicate piece of equipment,
built to a precision (and on a scale) comparable to a Swiss
watch.  Eventually it will need service - PMT2 is the one
that usually gets the most use and is  therefore likely to
be the one that needs replacement first.  We've had similar
problems and likewise faced up to the need for service and
replacement.

Have other people noticed, as I have, that electron microscope
users don't seem at all surprised that their instruments need
service and replacement parts on a regular basis and yet users
of optical microscopes costing just as much expect them to last
forever with no attention?  I guess it goes back to the days when
the money was just paying for precision, and there were no
electronics and little mechanical complexity.  (My 80-year-old
Zeiss "jughandle" is pretty much as good as it was when new).

Modern confocals are hugely complex and the key thing is not
whether they need attention (they all will) but how good the
service you get is.  And at least in this neck of the woods
Leica are outstanding on that score.  Our TCS SP2 MP clocked
up almost 1,500 hours of paid use last year, making it our most
heavily used piece of imaging equipment (Out of 3 SEMs, 5 TEMS,
one STEM, 2 AFMs, 3 confocals and 3 digital imaging optical
microscopes).

                                              Guy Cox




--
Associate Professor Guy Cox
Electron Microscope Unit, F09
University of Sydney NSW 2006
+61 2 9351 3176