>Hello,
>
>We have been debating the pros and cons of an inverted against an
>upright microscope for confocal applications.
>
>Are there any experiments that can be done ONLY using an upright ?
>
>Would appreciate any comments/suggestions on this.
>
>With Best Regards,
>Sanjay Khendry
>------------------
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>Optima, India
 
Tissue culture cells like to sit on the bottom on their culture chambers
and the images of them will be less degraded by the spherical aberration
caused by using oil lenses on water embedded specimens if the focus plane
is near to the coverglass.  This line of reasoning suggests the inverted
microscope.
 
However, if you use water-immersion lenses (as should be the case for
living cells) then an upright configuration is usually preferred because it
is usually easier to maintain the drop of water between the objective and
the specimen if you have gravity on your side.  Water drops can be held in
the right place in the inverted configuration in a number of ingenious ways
(discussed previously on this list) but failure of these methods can allow
water into the objective itself, a situation that may cost $1,000 to
eliminate.
 
Another consideration is the fact that inverted microscopes are usually
more sturdy in construction and are preferred for use in locations with
high vibration.
 
 
Jim Pawley
 
                   *****************************************
Prof. James B Pawley,                                        Ph.  608-263-3147
Room 1235, Engineering Research Building,                    FAX  608-265-5315
1500 Johnson Dr. Madison, Wisconsin, 53706.
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