U of S | Mailing List Archive | alt-photo-process-l | Re: uncurve/curve comparison on Loris' website

Re: uncurve/curve comparison on Loris' website



----- Original Message ----- From: "Katharine Thayer" <kthayer@pacifier.com>
To: <alt-photo-process-l@usask.ca>
Sent: Thursday, September 27, 2007 10:21 AM
Subject: Re: uncurve/curve comparison on Loris' website


Interesting. I'd characterize that comparison very differently; the
bottom one, to my eye, is heavily cyan-biased; the upper one simply
cuts the cyan way back to match the rather undersaturated yellow and
magenta. It's an interesting effect, and certainly if the same
pigment mixtures are used for both, a special curve for the cyan
layer would be necessary to cut back the extra cyan without
disturbing the other colors. I'd do it by adjusting the cyan pigment
downward to match the saturation of the other colors to get the same
effect. Different roads to the same kingdom.
Katharine

Both prints have the same pigment mixes and the only difference is in the curves between the two prints, otherwise to my way of thinking the illustration would have been a false comparison, and I think it is a very good illustration for the benefits of correct curves and a correct method to make curves (both prints are curved, the too dark one I took a generic gum curve and used it the same for all layers). If cutting down cyan gets one to the same place, that'd be great, too.

My process that works so well for me has been that first you figure out the approximate color saturation of your mixes, and then do your calibration on those mixes, without varying the mixes until you get a handle on the process. If the print comes out flat as in your example, Katharine, then either your method of deriving curves is not doing what it should for you or your curve is not. Something in your workflow is in error. It doesn't mean curves don't work for gum, or that it is an illogical or unnecessary method to try--just that for you it seems curves do nothing for your workflow. And I wonder why you are going the curve direction since your former tricolor process was so perfect? The only reason to my way of thinking to even attempt to curve gum is if your prints aren't turning out well. Otherwise, even a lowly bitmap negative with no curves works beautifully if one adjusts the workflow/saturation/etc. to match. I loved the look I got from that method, very soft. (Hmm, if I remember, I was accused of leading students astray for teaching that method, though.....)

And as I said to Charles, the number one reason for incorrect negs is not selecting "no color adjustment" once, or twice, in the printer driver dialogue box. OH, and not selecting the paper choice that lays down the most ink, too--it should be glossy but on the 4000 it is actually semi-gloss. Charles, I have the 1800, too, and I agree it is a namby pamby negative maker.

In my case, curves made an immense difference in my prints. But to a beginning gummist who is probably not going to make gum their process of choice, I think it is perfectly valid to teach the less complex methods. I was really pleased at the great prints my last class got with uncomplex negatives, and I seemed to have "hooked" about 30% of my students to continue in gum, and in the more measured way, too.

Also, Marek, I agree with you that the charm in gum is in the imperfection ultimately (unless too flat, muddy, dull, dark). Case in point--Judy's acid colored Kinky image. I love that image! I was just at an opening last night of a former student, all gums, and he hung a print in the show that he wasn't going to because it was too offcolor cyan and gritty. But it was perfect for the meaning of the piece--a lonely little boy. It pleases my heart to see any student continue in gum. Makes all my effort so worthwhile.
Chris