Many have tried to measure the "resolution" of the MRC-600, both in
refection and in fluorescence.  However, when you do, don't forget that,
dedpending on how much accessory optics (for DIC of Widefield fluorescence)
you have in the column, the laser light is unlikely to fill the BFP of many
objectives.  This is particularly true of high-NA, low mag lenses (10x,
0.45, 40x, 1.3 etc.) but less true of high-NA, high-mag lenses such as the
100x 1.4.  As resolution (particluarly in reflection from a smooth surface
at normal incidence) is only proportional to that part of the BFP through
which light actually passes, this fact means that the "resolution" measured
with the 100x lens may be quite a lot better than that measured with a 40x
lens of the same NA.
 
You can estimate the size of the laser beam in your instrument by going to
maximum zoom (or stopping the scanning completely) and looking at the size
of the spot in the alignment prism.  Remove the prism, measure the circle
inscribed on its top surface with a ruler and then replace, estimate the
size of the spot compared with the ring and compare this with the size of
the clear area of the objective, viewed from the BFP-side.  Remember,
z-resolution is proportional to "effective" NA squared.
 
Cheers,
 
Jim Pawley
 
 
>Ellen Lumpkin wrote that she has a protocol for estimating axial
>resolution for the BioRad confocal microscopy.
>I use an MRC 600 and I am  very interessted in this protocol.
>I also would like to know if anybody has measured axial resulution
>for an MRC 600.
>
>Thank you very much.
>
>Sabine Fischer
>Edinburgh University
>ICMB
 
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Prof. James B. Pawley,                                       Ph.  608-263-3147
Room 1235, Engineering Research Building,                    FAX  608-265-5315
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