I suspect along with others that the culprit is the new TMAX 100
UV-blocking base. Here's an image showing the results of a Van Dyke
Brown printing test comparing old TMY, new TMX, and Ilford HP5+ on the
same sheet of paper:
http://my.net-link.net/~jsmigiel/images/technical/TMX_TMY_HP5.jpg
The center piece of film is TMX and has printed several steps lighter
than the other films given the same exposure on the same sheet. IIRC
the visible base fog of HP5+ was about double the TMAX but it has
printed to a greater max d. Also, there had been some discussion
regarding the use of an alcohol soak to remove the UV-blocking property.
Half the TMX sheet was treated in alcohol and it made very little
difference in the printing properties.
I suspect similar results would be obtained using cyanotype or any other
printing process that employs UV for the print exposure.
Joe
>>> rskmd83@hamptons.com 11/13/05 8:56 PM >>>
I am having some difficulty with my cyanotypes and I am hoping for some
help.I get a very rich, deep blue on areas coated beyond the negative,
but
even the unexposed areas of the negative are very weekly colored. I have
used exposures up to 45 minutes in my homemade exposure unit with a bank
of
8 bulbs about 3 inches above the contact printer.
I use T max 100 predominantly. Any suggestions?
Received on Mon Nov 14 07:29:59 2005
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