Barry, Ken (email@example.com)
Mon, 12 Apr 1999 14:40:47 -0400
I spent the weekend trying Liam Lawless' process in P-F #2 as modified by
the numerous postings to the Alt.photo list.
I used a recent pyro developed Bergger 200 4x5 negative. I was enlarging to
5x7 to minimize cost while learning (I have never enlarged a negative before
and just started with alt processes last June with Ziatypes.)
It seemed that the 3x exposure was better than 6x even though I am using a
pyro developed negative but my problem was that the flash was much more
"sensitive" than the article would indicate.
My 30 second exposure (f 32) was showing a max density of 4.25 with no
flash, 3.42 with 1 sec flash, 1.45 with a 2 second flash, .91 with a 4 sec
flash, .64 with a 6 second flash and .56 with an 8 second flash. (It took me
a while to get to this negative to find this out; first I was using a
different print developer and couldn't get consistent results, then I mixed
the PQ developer but still spent too much time finding the right exposure at
30% flash until I finally printed flash test strips and before you know it,
the box of 25 sheets is empty.)
This means that my 3.0 negative would use about a 3% flash and 1.9 will be
around 1.5(?) seconds or ~5% and my 1.5 negative would be ~7% compared to
articles' 15%, 30% and 45%!
Does it appear that I am doing something extremely wrong? Could it be that
the 4x5 to 5x7 is making the flash more effective (I am trying to relive my
college physics classes on light behavior; 1/r2) or could the pyro negative
stain block so much light through the negative that the flash without the
negative is much to bright.
I am going to buy a step wedge and try again with the flash at the next
higher f-stop on the lens and also use some non-pyro negatives. I
appreciate any comments you may have and also thank Liam for doing the
research and writing the article in the first place, I have really enjoyed
tying to get this to work (for me.)
Ken Barry (firstname.lastname@example.org)
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