Re: black vs. color inks and gum

From: Katharine Thayer ^lt;>
Date: 11/15/05-09:38:32 AM Z
Message-id: <>

This is interesting, Chris, thanks. I've never done a side-by-side
test as a test, but I've always said that I didn't understand what all
the fuss about negatives was, since I made negatives every which way
before acceptable inkjet printers were developed for photo printing,
and it seemed to me that all the different methods I came up with for
making negatives worked fine.

I had pretty much got bored with making tricolors by the time Epson
developed the first photo inkjet printers, so 99% of my tricolors were
printed from bitmapped color separations, the curve taken from the
silver curve in Dan's first edition, (same curve for all colors)
printed on a 300- and then later a 600- dpi laser printer. I hate to
keep bringing up this same print as an illustration, but I put only a
couple tricolors on my website, since the purpose of my gallery there
was to show the range of different effects gum is capable of rather
than to show off my work, so here it is again:


On Nov 15, 2005, at 6:41 AM, Christina Z. Anderson wrote:

> Good morning,
> Over the weekend despite my many mistakes I finished testing side by
> side black ink only and colorized negs for gum.
> Thanks to Rodolpho Pajuaba for the suggestions to remove the venetian
> blind effect; the black ink reprint of the negative did not contain
> those waves of density when i switched to 16 bit and selected 1440
> instead of 2880 in my print driver.
> Well, I'm hard pressed to make any conclusions except one: with
> correct and separate curves for magenta, yellow, and cyanotype, my
> gums look great. BUT, since with the PDN system I had developed 6
> curves, 3 for black ink only and 3 for color ink only negs, both sets
> of images were fine. Both were a great improvement over my former
> methods of gum printing and my former curve. But side by side, black
> ink and color ink only negs both "do the gum job".
> Next I am going to bitmap the image with black ink only curved, and
> see if Howard Efner's bitmapping is even sufficient enough. If the
> lowly bitmap does a great gum, then I would suppose gum is the most
> flexible negative-using process there is. After all, we're talking
> about hardening gum in a layer, essentially not a photographic process
> almost per se.
> Certainly with palladium, salt, straight cyanotype, argyrotype, van
> dyke, and traditional silver paper, I would use Pictorico and
> colorized negs for the grainless, tonally smooth negatives. Howard,
> I've lost your post: what resolution did you bitmap at?
> One thing I will say is that with correct curves the gums are soo easy
> to develop. No dinking around removing color from areas it shouldn't
> be.
> Will I stay with black ink only on PWOHP vs. Pictorico? This is where
> I am undecided. Pictorico is so nice and stable and not flimsy even
> though it is expensive. I think I need to do a few more side by sides
> and see if there is any slight edge.
> Chris
Received on Tue Nov 15 09:39:44 2005

This archive was generated by hypermail 2.1.8 : 12/01/05-02:04:50 PM Z CST