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Tricolor gum, order of layers

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  • Subject: Tricolor gum, order of layers
  • From: Loris Medici <mail@loris.medici.name>
  • Date: Sun, 28 Sep 2008 03:45:31 +0300 (EEST)
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After the 4th try, I decided to go back to my original practice of
printing in the following sequence: Y, M and C. I had changed this order
in favor of C, M and Y later because that seemed more logical. But since
the yellow I prefer is semi-transparent, when printed last it gives the
image an ugly haze, which lowers dmax and contrast. (The semi-opaque and
opaque yellows are worse in this aspect.)

Starting with the C layer seemed a better way of doing at first, since
it's the most problem prone layer + (for those who register by eye,
looking at the printed image) registration is easier. That way, I could
discard / reject the print early if the cyan layer goes bad. (BTW, ease of
registration wasn't an issue to me since I use semi-opaque paper

Now, because of my pigment choice + the fact that it seems more logical to
start with the lightest color and finishing with the darkest, I think I'll
do it in the Y M C order.

See the first two layers here
1. Cyan: http://tinyurl.com/4z6zp2
2. Cyan + Magenta: http://tinyurl.com/3hyzhh

I guess both layers have too much pigment for tricolor work.

Since both the Cyan PB15:3 and the Magenta PV19 are intense pigments, it's
very hard to squeeze very little (less than what I used for the sample
above) pigment from the tubes (into 2.5ml gum, for a print size of
8,5x11"), I guess I will also have to prepare stock gum/pigment mixtures.

Whew! Tricolor gum is much tougher than I thought...

P.S. Dear Keith, the 18lbs translucent inkjet bond is wonderful for making
paper negatives. Thanks much for suggesting it! The results are much much
better compared to ordinary photocopier paper and the exposure times are
much shorter too (by -1.5 stop, my current exposure time with UVBL bank
and 10% ammonium dichromate is around 6:20).