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*****

The major microscope companies offer to 'refresh' (either refurbish or 
replace -- their choice) lenses for 50% of purchase price. Check with 
your local sales rep.

Suggestions:

* (that I never did): for inverted microscope lenses, consider storing 
them at nights and weekends front element down (i.e. in their storage 
container).
* if the lenses and microscopes are heavily used, consider the lenses as 
consumables (that happen to be 'refreshable' at half of list price).
* consider making some (or all?) of the microscopes very specialized. 
For example, at my previous position (UMiami) we had one inverted 
microscope that had only 'dry' objective lenses (and no bottles of oil 
in the room). The confocal microscope in the adjacent room had almost 
entirely oil immersion lenses (20x/0.7 oil, 40x/1.3 oil, 63x/1.4 oil, 
plus 10x and 5x dry).
* $8,000 lenses (refreshable for $4K) is not bad ... $11,000 to $18,000 
lenses start failing.

best wishes,

George
p.s. Specializing microscopes for low mag histology is a waste of time: 
with respect to low magnification lenses for histology and 
immunohistochemistry, my best investments in both the core's I managed 
(L.A. and Miami) was the ~$2,300 Pathscan Enabler slide scanner. 
Equivalent in resolution to a typical 5x objective lens, but entire 
slide (up to 36x24 mm) in two clicks, with perfectly flat illumination. See
http://works.bepress.com/gmcnamara/1/
or
http://home.earthlink.net/~tiki_goddess/



On 5/27/2013 6:37 PM, Claire Brown, Dr. wrote:
> *****
> To join, leave or search the confocal microscopy listserv, go to:
> http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
> *****
>
> We are relatively routinely seeing oil inside of our Zeiss 63x oil immersion lenses. You end up with a bead of oil inside that acts as a lens itself and the lens is unusable.
>
> As far as we can tell, it usually happens after prolonged use over many years. We are at a point now where our lenses are "old" and Zeiss cannot repair them because the parts are no longer available. It costs us $6-8,000 to replace them. With 13 microscopes we have one lens failing every 6-12 months or so. I can't afford to keep replacing these lenses and with this becoming a "routine" occurrence I want to seek out advice about why this might be happening. Our users are well trained and I don't think it is neglect by them. I think this is due to routine use.
>
> I have two questions:
>
>
> 1)      "Is there a defect in how these lenses are made?"
>
> For example, perhaps the seals on the front lenses degrade over time - we inspect our lenses regularly and many that have had oil inside have no obvious damage by visual inspection. Maybe they need to be resealed every year or two, maybe an internal seal degrades over time? Preventative maintenance of these lenses or a change in how they are manufactured would certainly cost less than $8,000 I would think.
>
>
>
> 2)      "Do people have a similar problem with oil immersion lenses from the other major manufacturers?"
>
> I look forward to some input here.
>
> Sincerely,
>
> Claire
>
> -------------------------------------------------------------------------------------------
> CANADIAN CYTOMETRY AND MICROSCOPY SYMPOSIUM - MONTREAL JUNE 13-15 - http://www.regonline.com/ccma-accm2013
>
> Claire M. Brown, PhD - McGill University - Assistant Professor, Physiology - Life Sciences Complex Imaging Facility Director
> 3649 Promenade Sir William Osler - Bellini Building - Rm 137A - Montreal - Quebec - H3G 0B1
> 514-398-4400 ext 00795 (Phone) - 514-677-7493 (Cell) - 514-398-7452 (FAX)
> [log in to unmask]<mailto:[log in to unmask]>  - http://www.mcgill.ca/lifesciencescomplex/core/imaging
>
>    


-- 



George McNamara, Ph.D.
Single Cells Analyst
L.J.N. Cooper Lab
University of Texas M.D. Anderson Cancer Center
Houston, TX 77054