>Are there any opinions (!) on whether fluor or plan apo objectives are more
>suited to imaging fura2 and indo1.

It depends on your plan-apo.  Some have virtually no transmission in the
uv.  Trying to increase the UV power to compensate can damage the lens.
Others do transmit reasonably well in the uv and can be used.  A fluor
lens will have higher transmission at all wavelengths since it has less
glass, but its chromatic correction will be less good.   This makes little
difference since neither lens is corrected in the uv.  Some expensive
lenses corrected into the uv have been announced from time to time -
check with the manufacturer of your microscope (but only if your pocket
is deep).
                                        Guy Cox

Dr. Guy Cox,   |                    ooOOOOOOoo
E.M. Unit, F09 |        #       oOOOO  |  |  OOOOo       #
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