Re: Glyoxal?

Yves,
Like many of your ideas, it's a good idea, but not a new idea, and
unfortunately not a very practical idea. In order to come up with
generalizable results, given the number of variables that would need
to be controlled, for every question we would need hundreds of
observations under scores of different conditions; the task is mind-
boggling, even when the workload is shared, as you suggest. Since
there are at most a handful of people who are interested in the
larger questions and willing to engage in testing for the sake of
testing, I just don't see how we could cover all the variables in
order to get results that could be universally repeatable. The reason
I recommend that people simply do their own tests to find out what
works for them, is that this is truly the most effective, efficient
way to get to making gum prints, not because I'm not interested in
the larger questions. But as a statistician, I have to be realistic
about the possibility of answering the larger questions in any
meaningful, reliable, way, although I do keep chipping away at it as
much as I can.

This was before my time, but I seem to remember reading in the
archives about a group testing of gums, where different people tested
different gums in their own environments, and got different answers
as to which were the best gums. Then they traded samples, so that
they were each using exactly the same batch of gum as the other
person was, and they still got different results, and decided the
different results must be due to the different water in the different
places. There are just too many uncontrolled variables to be able to
come up with repeatable answers. It's not that it hasn't been tried,
it's just that it's not as easy as it seems.

Glyoxal has been used successfully by many gum printers without any
yellowing problem, and though yellowing has been observed by some,
most who have observed it have found that rinsing the paper
eliminates the problem. Chris is the only one I know of who has
reported that rinsing doesn't eliminate the yellowing, although she
reports knowing of others. Even if you came up with some kind of
universal answer, which I'm very skeptical about, people would still
make their choices based on personal preference. I prefer glyoxal,
(although when it comes to personal preference, I really prefer a
mixture of gelatin and gesso, that's my very favorite size. But I
don't like cleaning the gesso out of the measuring cup; it's really a
messy job. Maybe if I learned to mix the sizing in a cottage cheese
container or something, I could use this sizing all the time, and
just throw away the container each time). But at any rate, glyoxal
really works quite well for me, as you can see from my tricolors for
example, see enlarged detail here:

http://www.pacifier.com/~kthayer/html/optrans.html

The graininess in the left picture is a function of the pigments, not
the sizing. With glyoxal, I get a smooth paper, none of the
grittiness that Chris reports, white whites, and a fine print. From
the popularity of glyoxal over the last few years, I would be quite
surprised if I'm the only one who finds it a fine size.
Katharine

On Jan 16, 2006, at 8:45 PM, Yves Gauvreau wrote:

> Hi again,
>
> this is just an idea that came to me after reading Judy and
> Christina. There
> are so many variables at play in each part of any process that it is
> basically certain that our experiments aren't repeatable by other
> most of
> the time if not always. I'm not saying that with the intention of
> being rude
> to anyone on this list but I'm convinced that most of the time most
> experiments are mostly useful to the one who did them and most
> probably
> useless most of the time to others. I think it would save all us a
> great
> deal of time if we didn't have to repeat all experiments on our own
> all the
> time because most of you I'm sure already know that others
> experiments have
> proven themselves not very useful so many time in the past and know
> you do
> your own.
>
> That doesn't have to be the case or at least we could try to
> improve the
> usefulness of our tests probably both for ourselves and to others.
> I don't
> pretend to have a clear and definite answer to all this but I'd
> surely like
> to try finding a better way. I would go further then that, we could
> also
> devise some scheme to split the workload. Before that, I think we
> should
> address the first problematic and I think a potential avenue of
> solution
> would be to agree on some form of standardisation but as I said
> earlier I
> don't care who comes up with (a)the solution or what it is as long
> as we all
> agree on something and that it works.
>
> I just hope this doesn't sound to awful,
> Yves
>
>
>
> ----- Original Message -----
> From: "Judy Seigel" <jseigel@panix.com>
> To: <alt-photo-process-l@sask.usask.ca>
> Sent: Monday, January 16, 2006 9:10 PM
> Subject: Re: Glyoxal?
>
>
>
>>
>> On Mon, 16 Jan 2006, Christina Z. Anderson wrote:
>>
>>> Your tests prove that glyoxal does yellow, but not always. My tests
>>>
> prove
>
>>> that glyoxal does yellow, too, but in degrees. I would therefore
>>> hope
>>>
> that
>
>>> our tests that we have spent so much time on are worthwhile to
>>> ourselves
>>> personally and to others on this list. How else would we develop a
>>>
> database
>
>>
>> (etc.)
>>
>> Before we abandon the principle of cause & effect, a suggestion:
>>
>> I found that every alkali I tested turned glyoxal yellow or orange
>> sooner
>> or later, very or somewhat. And we know that MOST (if not all)
>> contemporary art papers are buffered, that is, stoked with alkali to
>> counter the acid effects of air, or rain, or water, or more
>> probably the
>> nasty chemicals used in making the paper or the water the factory
>> uses.
>>
>> So it could be the paper buffering that causes the yellowing. Why
>> don't
>> all art papers yellow all the time in glyoxal? Possibly the water
>> supply.
>> Most of us use tapwater from different sources -- so they're
>> different.
>> There's also the "pump house" where civil servants add different
>> ingredients according to season and weather, needs of the moment &
>> theories of the state legislature.... So our summer water may be
>> different
>> from our winter water, etc. etc. etc.
>>
>> Should a day come when I have time for more tests, I'd use the pH
>> pen to
>> test pH of paper, and then test pH of the water. We do know that
>> some
>> water sources are very alkaline (they can bleach your cyano
>> overnight).
>> That might also yellow your unrinsed glyoxal paper. But some water
>> might
>> be relatively acid, & counter that tendency of glyoxal. I'd also
>> test tap
>> water for development versus distilled for both mixing and
>> developing...
>> which might also shed light. Or dark.
>>
>> Plus art papers vary batch to batch & by the season they're made
>> -- I'm
>> told that's because the water they're processed in changes...
>> Friend told
>> me some of his paper customers only buy paper (for platinum) made
>> in, I
>> think it was winter, but we don't know when the paper we buy from
>> Sam's
>> art store, or online, or find in a drawer was made.
>>
>> The only trouble with this theory of course is that some of us
>> watching
>> this have found our STUDIO is consistent, even as the seasons
>> change. I
>> have no theory for that.
>>
>> Judy
>>
>
>
Received on Tue Jan 17 10:02:37 2006