Re: Gum variables

FotoDave@aol.com
Fri, 12 Jun 1998 10:11:26 -0400 (EDT)

In a message dated 98-06-12 09:49:56 EDT, FotoDave@aol.com writes:

<< Well, these kind of things are so hard to describe in words. Maybe one day
I
will try to write a better description.
>>

Well, after logging off, I thought of a slightly better explanation and re-
signon again. :)

Considering the effect under discussion and assuming other parameters (paper,
sizing, development) are the same, we have to at least consider the following
parameters / variables:

amount of pure pigment
amount of gum in the watercolor "pigment"
amount of gum we add
amount of dichromate (powder)
amount of water

and we can change the amount of one variable at a time and study the effects,
but as pointed by Wayde, the number of tests will be large. Secondly, he (and
myself) also pointed out that one variable might affect different things.
Maybe it had been difficult to visualize, but with this example, it can be
understood:

Say you hold everything constant and only change the amount of water. It
affect the viscosity of the whole mix (thus might affect brushability and
thickness of coating). It also affects the suspension of pigment in the mix
(thus might affect staining). It also affects the amount of dichromate (thus
might affect speed and contrast). But all these were affected not at the same
point and they all affect the final print.

Therefore even if you just change ONE variable at a time, after you do an
exhaustive tests, all you have is a big set of working data, very useful but
might still not be able to explain things. Most likely, you won't be able to
say something simple like "adding water will change this and that" or "adding
dichromate will change this and that...."

So in order to have a good explanation of the whole thing, one needs to get
into physical modeling, which I am working on. For that you need to think
about what is actually going on, and that's why I used "mind microscope."
Since your mind microscope is not truly a microscope, it does not give you
true explanation. It only gives you hypothesis that seems to explain the
phenomena. Then you can conduct tests to verify or disprove your hypotheses.

But of course, I am not working full-time on this. :( But you will hear
from me. :)

Dave