Terry, I assume you mean for other processes than gum. I'm just
finishing a round of tests of 3 gelatines with 3 hardeners & 3 gums with
2 hardeners as size on various papers. For the particular gum emulsion I
used, paper with no added size was *far* better in most cases. That may
have been because the emulsion I used was thick, had a lot of pigment. It
had lots of nice steps on paper with no added size, many fewer on sized
papers.
And that is the main conclusion from a fairly frustrating exercise --
frustrating in part because weather change in midstream seems to have
skewed half the tests. The only *certain* conclusion is that there are no
absolutes, each choice of size, colloid, pigment,paper, and proportions
works differently -- but we knew that..
However, here are a couple of questions about your de-ionized :
> light.. Coat the paper with the size at this temperature and dry immediately in
> a flow of warm air. Humidify the paper in a cupboard above a tray of warm water
> before sensitising.
Again, I assume you mean humidify gelatine for platinum or iron silver
printing -- but why do you dry the gelatine immediately? To keep it on
the surface? If so, why?
> For gum use a 3 % size for hardened substrates and inter coat sizing and dry in
> a flow of warm air.. But despite Judy's protestations the pterotype method using
> dichromated Gloy works better.
Terry, you have to define and quantify "works better." I have found that
dichromated gloy gives a less intense one-coat, flakes more and gives
flatter steps on many papers. So what's better?
> For pigment 3 and 5 and 5 and the same for carbon receiving tissue. >
What does "pigment 3 and 5 and 5" mean, or refer to?
When you say "purified water" is that what we call distilled? Do you use
it for gum sizing too? What's the advantage? (Paper is going to be
developed in tap water.)
Judy