U of S | Mailing List Archive | alt-photo-process-l | Re: Was Re: question on sizing, now fish eyes

Re: Was Re: question on sizing, now fish eyes

Just a couple thoughts:
I think as in all things gum there are a number of different answers to this
question and more than one answer can equate to a contributing factor. In
other words, some get fisheyes on unsized paper with gum but not on unsized
paper with casein. Some get fisheyes with gum with certain pigments more
often than others on sized papers. In Katharine's experiment, below, where
the coating "opens up" on Yupo, this is the fisheye that I am referring to.
It is sort of like when you are making bread dough and it will not "relax"
and so you leave it for a moment to let the yeast work in it and soften its
tendency to spread out into pizza crust or whatnot. Otherwise the bread
dough keeps retracting and doing these little tearing/separating things on
the surface.

My guess is it relates back to the viscidity discussion we had years ago in
that at a certain point of too much or too little even (!) water, the
coating is unable to hold together and retracts, and this ability to not
hold together can be exacerbated by sizing or pigment qualities or pigment
additions or whatnot. But sizing in no way is the main nor only issue
because I always size and I only occasionally get fisheyes---with
magenta---whether first or last coat.

A test if I had time would be to use unsized and sized and coat side by side
same mix ratio of yellow and magenta and see if one could reproduce
consistent results.

But Henry, you are right in that generally they can be worked and brushed out, in my experience as well.

Christina Z. Anderson
----- Original Message ----- From: "Henry Rattle" <henry.rattle@ntlworld.com>
To: <alt-photo-process-l@usask.ca>
Sent: Wednesday, September 10, 2008 12:04 PM
Subject: Re: Was Re: question on sizing, now fish eyes

On fisheyes -  I get them from time to time and have always put them down
some inconsistency in the sizing (brush-coated 3% gelatine with
hardener). They always brush out once the gum-pigment layer begins to get
bit more viscous, and as far as I can see have no effect on the final


On 10/9/08 18:28, "Katharine Thayer" <kthayer@pacifier.com> wrote:

Laura, I can't find the other thread you referred to so maybe it was
under a title that wouldn't identify it as being about a coating
problem with Payne's grey.  However, since "Payne's grey" isn't a
pigment in and of itself, but is simply a convenience mixture of some
blue (different manufacturers use different blues) and lamp black,
it's unlikely that it would behave in some way that would be linkable
to the color name "Payne's grey."

When I got your post, I thought "good timing," because I've been
planning to get back to my troubleshooting page, which I've been
promising for a couple of years. So I went downstairs even before I'd
had my shower,  to make fisheyes to show you.  But as I said, I
seldom encounter fisheyes, so it wasn't such a simple job to make
them happen.  The "fisheyes" I occasionally get (on Arches bright
white sized with gelatin-glyoxal) are very small, almost like
pinpricks, so maybe they really don't qualify as fisheyes, except
that they appear in the same way as larger fisheyes, as a visible
lateral retraction of the emulsion from areas of the paper.   Anyway,
this morning I couldn't make that happen on Arches bright white, so I
pulled a piece out of my stack of different kinds of paper sized with
different stuff; this one  happened to be Lana sized with gelatin and
glutaraldehyde, and got the kind of fisheyes I'm talking about; I've
scanned that for you.

I also tried to make the bigger kind of fisheyes, the ones that open
up to 1/4" or 1/2" wide and really look like fisheyes,  by coating on
Yupo,  but was unsuccessful until I added a little water to the mix,
and then got some of these fisheyes.  I took a picture of this with
my cheap digital point and shoot; it's blurry but I hope you can make
it out.  I'd be interested to know if people mean one or the other,
or something different, when they refer to "fisheyes."

In both cases I left the fisheyes as they first appeared rather than
attempting to brush them out, so as to not obscure what they look
like in their undisturbed manifestation.


That page is temporary, just uploaded for sake of this particular

On Sep 10, 2008, at 3:01 AM, Laura Valentino wrote:

Does anyone have a scan of this "fisheye" effect they could share?
A couple of weeks ago I wrote about a "bubbling" with payne's gray,
so I also wondered if it was something related to the pigment. Or
it could've been because it was a different brand of paint, because
that was the only variable that changed from the other colors I was
trying. I washed the layer all away (after learning here I could do
that) so I can't share the effect I got.


zphoto@montana.net wrote:

Also, because I get it consistently with magenta and not
yellow I think it must have some relation with the coating
but maybe not the gum, maybe the pigment or who knows.  I'll
watch it for a while and see if I can determine any other
factor that might play into it.