Re: What are the advantages of using Cyanotype as the first layer fortri-color gum prints? Paper Problems...

Loris Medici wrote:
>
> Well, I can tell that my recent Cyanotype 2 prints on HP Cot320 paper are
> extremely sharp; using 2880dpi Epson 1290 (1280 in the States) digital
> negatives made on Ultrafine Crystal Clear, lightsouce: 8 BL tubes spaced
> 1.5cm (5/8") from each other, distance to contact frame glass 3.5cm (1
> 3/8"). Prints are so sharp that you can clearly and cleanly see every square
> of the 2x2 pixels checkerboard pattern printed at 360dpi! (And I'm sure it
> would also show a clean 1x1 pixel pattern also - if the printer was capable
> to print it cleanly... Unfortunately it's not.)
>
> Do you think that gum is capable of making prints rivaling / surpassing this
> resolution?

Hi Loris,
The only way to answer your question adequately would be to make the
2x2-pixel checkerboard and see how well it prints on gum for me,
(although I would answer from the get-go that I certainly don't have any
reason to believe that gum would *surpass* cyanotype in its ability to
print fine detail). Unfortunately my ancient system is self-destructing;
I can neither scan nor print at this time, but out of curiosity I will
do this when I get a new system up and running, if I haven't forgotten
by then.

My sense has always been that, though it's true that different papers
and different negatives print detail differently, the fact that the
paper has to be soaked constitutes the final limiting factor on
sharpness in gum printing. To quote myself from my website on this
issue: "Because the paper must be soaked during development and often
soaked more than once, minute details on even the smoothest paper will
be blurred somewhat by the paper fibers being raised and swollen during
the soaking. So gum will probably never print detail as well as some
other photographic methods will. However, gum can show much more detail
than many people believe."

I was thinking of commercial silver papers when I referred to "other
photographic methods" that would print detail better than gum, not other
alt techniques, but it's an interesting question. Since cyanotype also
requires soaking, it seems to me it would share the same limitation as
gum does, so if there's a difference it has to be something inherent in
the processes themselves that would account for more sharp detail in one
than the other. If I had the materials for cyanotype I would print them
side by side to see for myself if this is the case, but I'm a gum
printer, not a general-purpose alt-photo person, and though I've been
known to spend money just to find out something I'm curious about, I
won't buy chemicals just to do this comparison.

I strongly suspect that sharpness in gum is also a function of the
printing style. I print my gum very hard, meaning that when I've
finished and dried a gum layer, the gum cannot be redissolved even in
boiling water, let alone cold water. This results, I suspect, in finer
and sharper detail than could be achieved by a printing strategy which
yields a softer gum, and may explain why some of my deep blue gum prints
have been mistaken as cyanotypes by folks who should know the
difference.

I've read here that some people prefer to print so that they can
redissolve earlier dried layers of gum on subsequent soakings. Gum that
could be redissolved in this way would by necessity have to be much
softer than gum that cannot be redissolved, and by definition would not
be likely to hold fine detail very crisply, given its ability to soften
and even dissolve when wetted. So I'd guess that a gum print printed
that way would show less fine detail than a cyanotype, side by side, but
that comparison wouldn't provide an adequate test of the question
whether gum is inherently limited in how fine detail it can print, in
comparison to cyanotype.

The pictorico negatives that printed well for me on Fabriano Uno HP and
Lana HP and other fairly smooth papers, I can't use on Arches Bright
White, because this paper is so much smoother that the gum prints
printer artifacts on the pictorico negative that simply weren't picked
up by the other papers. This may be a coarser problem than what you're
talking about; I'd have to see for myself to know if this is the case.
Later,
Katharine
Received on Mon Sep 19 21:46:11 2005