From: Alexander L. Wallace (wallacea@cofc.edu)
Date: 03/08/01-11:35:08 AM Z
Re: Densitometers
For those of you who have a microscope lying around this may be of some
interest. The Minolta probe booster box contains an adapter to change to
tip from reading the ground glass of a view camera to reading the light
coming through the microscope eyepiece tube. By comparing the readings
with a calibrated step tablet, such as the Kodak t-27 I was able to get
very good readings from suitably small areas of negatives.
The incandescent bulb of the microscope gave enough light, though it worked
better by increasing the output by removing a blue filter behind the
frosted glass in the microscope base.
By directing a small high intensity light at the platform where you put the
negatives (or microscope slides) at a 45 degree angle it was possible to
get reflective readings from a print also. For comparison a calibrated
gray card from Kodak for copy work gave the compared reflective density
values.
Sorry, no experience with pyro.
Regards,
ALW
ps Minolta booser not needed,if you put a luna pro in a little box to
securely hold it against the eyepiece tube of the microscope it also will
work, but the range is limited by the luna pro sensor .
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