U of S | Mailing List Archive | alt-photo-process-l | Re: curves and gum and Christopher James book

Re: curves and gum and Christopher James book

Ohhh Yves,

A) I have no idea what you are talking about
B) I do not teach digital
C) I am apparently not anywhere near as smart as you.

But thanks for the thought!

----- Original Message ----- From: "Yves Gauvreau" <gauvreau-yves@cgocable.ca>
To: <alt-photo-process-l@usask.ca>
Sent: Thursday, March 06, 2008 1:29 PM
Subject: Re: curves and gum and Christopher James book


I find it very strange that a University professor finds that linearized
tone mapping is hitech when it's in fact the worst approach one can use. It
is as if you never eard of Tone mapping operators (Adaptive logarithmic
mapping (F. Drago, 2003), Dynamic range reduction inspired by photoreceptor
physiology (E. Reinhard, 2005), Gradient domain High Dynamic Range
compression (R. Fattal, 2002) and others)


----- Original Message -----
From: "Christina Z. Anderson" <zphoto@montana.net>
To: "Alt, List" <alt-photo-process-L@usask.ca>
Sent: Thursday, March 06, 2008 10:06 AM
Subject: curves and gum and Christopher James book

Hi all,
I am so thrilled with Christopher James' new edition of the Book of Alt
Proc. I'm not going to go into all the reasons why, just buy it you won't
regret it. Besides, it's got 3 Judy Seigels in there as well as Dan
Burkholder's piggies and Sandy King and probably more names otherwise you
all would recognize--can't say you don't get your money's worth from the
images therein!

Anyway, we've talked off and on about curves and gum, about different
negatives and gum, etc. etc. As we have probably always concluded, gum
suit itself to whatever practice is chosen, and there are many ways to
a cat.

Lately I have been working with a variety of negative choices to compare
practice (tricolor seps with individual PDN derived curves and colors for
each neg) with other lesser techy ways to teach students who may not have
Photoshop or even know what a curve is.  Bitmap, all ink negs, CMYK,
a curve out of my butt/on the fly...I have changed my teaching practice,
even, at MSU, to start the students with all inks greyscale neg one coat
first, then a Sam Wang duotone negative next (greyscale, no curve, all ink
neg), then an all inks tricolor third (no curve) and finally they will do
the grandaddy of them all, making a custom curve PDN Mark Nelson tricolor.
I find that starting students out low tech and moving to high is a way to
"hook" them into the process.

So when I saw the gum curve of Tony Gonzalez in James' book I about died.
It is hilarious. I mimicked it on my computer and found that the range of
tones he has in it go from about 26 to 92! He has essentially clipped
almost 200 tones! It looks like a flatline/dead person curve. However,
THEN look at his gum print (curve p. 351, gum p. 352-3)! The proof of
someone's working process is ALWAYS in the pudding.

I will try Gonzalez' curve but what I bet I will find is that I have to
alter other parts of my practice to fit into the curve, whether it be
pigment load or development time or dichromate amount or exposure time or
whatnot. The reason I bring it up is that as I tell my students, gum is
really not a photographic process. If you did a curve like that with
you'd have posterization and a gross print, but with gum which is just
hardening a layer where it needs to harden, it just isn't the same (e.g.
can choose an exposure time of 1 min vs. 8 minutes and get a thinner or
thicker layer of hardening which is not possible with BW printing or even
pt/pd--certainly not as much variability.)  And Gonzalez looks like he is
just squushing all his tones into the narrow range of stops that gum
represents, being a shorter scale process than other longer ones like
It looks like Gonzalez teaches at Queens College, CUNY so if he ever has
exhibit I would run to it.  Anyone on the list know him?  I wonder if he
a student of Sarah Van Keuren's?

So check out the book--it'll definitely spur the creative alt juices going
with the images alone, much less the information.

Christina Z. Anderson
Assistant Professor
Photo Option Coordinator
Montana State University