Eyedropppers and UV fluorescent tubes

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From: John Richardson (jrplatinum@earthlink.net)
Date: 06/02/00-02:39:44 AM Z


If you are using eyedroppers:

I just replaced the black rubber bulb on one of my eyedroppers for
ferric oxalate as it had deteriorated and was depositing black specks
into my DOP sensitizer. I find this needs to be done every couple of years.

I just replaced my 48" BL tubes with Super Actinic VHO tubes. This cost
$21 per tube and required 2 electronic ballasts (which power 4 tubes
each) at $175 apiece. These tubes put out 110 watts each, and have an
internal reflector to direct the light downward. I did this because I
am making prints for another photographer which routinely require 30-90
minute expsures from lightjet 5000 negatives.

Preliminary testing indicates that this setup requires about 1/3 the
exposure time. What used to be a 14 minute exposure using my Metrolux
with sensor, now is a 5 minute exposure.

I decided to run a set of step wedges with the new tubes as per
instructions in Dick Artentz's new book. Using B&S oxalate #1, no
oxalate #2, with 90% palladium and 10% platinum yielded 13 steps when
wet and 15 steps (including 90% black) when dry. I will report further
results when complete, including my complete processing instructions.

John Richardson


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