Jakob:
We have a Zeiss LSM 310 with a Coherent Enterprise UV laser, and our
biggest complaint with the system is the inconsistency of the UV.  (We
also have a HENE (543 nm) and a multiline Argon (488/514) which rarely,
if ever, display problems with uneven illumination).  Our multiple
service calls with Zeiss usually involve a request to realign the UV
laser, a task which only one of their service technicians seems capable
of completing successfully.  We have received various explanations from
the technical representatives of Zeiss for the UV drift: heating of the
lamp housing, screws becoming heat sensitive, and that the model we have
(310) was not designed to house a UV laser.  We were assured that the
410 and 510 were redesigned so as to accomodate the UV far better.  Your
posting is very interesting in this regard, and something to consider
since we were hoping to purchase a 510 sometime in the near future
(pending grant approval, of course!).  The only suggestiion I can give
you is to make sure the technicians realign the laser, check all
wavelengths with a multilabelled sample and phase overlay, and keep the
path of the laser free from heat sources.  We also had some success with
using some sort of adhesive to lock the screws in place around the
tower.  Although the drifting still occurred, it occurred less
frequently. Pinhole adjustments are also important.  Best of luck, and
keep us updated if you have any new explanations.

Linda Mayernik
Research Assistant

--
Confocal Imaging Core Facility
Karmanos Cancer Institute &
Center for Molecular and Cellular Toxicology with Human Applications
Wayne State University School of Medicine
6339 Scott Hall
540 East Canfield
Detroit, MI 48201
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