> >And speaking of clearing, among the several methods you tried, there was
>> no hypo clearing agent or sodium sulphite, <
> I have built a fume cupboard around my photographic processing sink and do
> all my pongy chemical mixing in there.
>
>But if we're talking for the world at large, which may not have a built-in
fume cupboard, and can buy HCA and/or sodium sulphite with their regular
supplies, while perhaps not so easily getting bisulfite, or sulphuric acid,
I would tend to think in terms of HCA,etc. -- especially since you say you
"found them very similar."<
Sure but I will test them again It is a few years ago, and my memory is not
what it was
>Philip (or someone) posted some awful warnings against sodium dithionite
last year, as I recall, and that might be still harder to get. So unless
it has some wonderful virtue (such as removing wrinkles) it seems
unappealing.<
but it would be nice to know as I have a few wrinkles that are in need of
urgent attention :-)
> >3. Some people would be antsy handling (or even getting) sulphuric acid.
> (And it isn't clear to me that it has any advantage except in gross
> over-exposure.)<
>
> This is perfectly understandable, but as you have said on a number of
> occasions that there are a lot of very nasty things in the kitchen cupboard
>that line about the kitchen cupboard is Terry's<
Ok but you have said something very similar about roach poison and stuff.
>and a 1% sol is very weak.I can give you three main advantages to the use
> of this clearing agent :-
>
> 1) It is the strongest agent
>
> 2) It is the fastest average time in fresh solution 30sec's to 2min's
>
> 3) It will get the stain down to almost base white on paper and actual base
> white on Synteape or any other impervious substrate
All other things being equal, the 1% sulphuric sounds good -- no powder to
mix, as well. I would still want to give it a pH check on completion.
Good idea
And for what it's worth, I mention again what has been for me a handy
method of dealing with such acids, especially sulphuric: I go into crisis
room with plastic apron, good gloves, a safety litre of water and as many
wits about me as possible (ie not in rush or distract mode) and make a 10%
"stock" solution which I then work from.
Yes I work in a similar manner in my fume cupboard I also wear plastic
protective glasses my wife says they make me look like a Martian
> Fotempera process.It is a totally consistent process, it works exactly the
> same time after time.
> In 1994 I was invited to take part in a symposium with
> David Sopick,and John Pollard at RMIT in Melbourne Australia, we staged a
> group exhibition of our work, took part in a public forum, also ran
> concurrent workshops over three days,at the end of which we had a
> throughput 36 students,all the students who worked with me achieved
> finished work whereas only a few managed to produce finished work in David
> And Johns classes,, both John and David were working the classic gum
> processes whereas I was employing the Fotempera, both my friends David and
> John are talented artists, experienced teachers, and skilled practitioners.
> it was the process that made the difference.
>Peter, you may simply have proved that Scopick & Pollard are not very good
teachers... Of course the Fotempera process, which I haven't tried, <
I think this statement is totally unprofessional,what ever you may think of
David and Johns writing this does not give you cause to caste doubt on
there professional ability as teachers, you weren't there so you do not
know, If I had been using the gum process I would have had similar
problems.
>There probably are more variables in gum printing than Fotempera (like
paper, for one thing, since I take it Synteape is always the same), <
This is the crux of the matter , for instance I can go from
coating-drying-exposing-development in under four (4)mins also with a
second coat of the same colour
in well under six (6)mins this means I can work very fast, and therefore
this gave me a considerable edge when working to a tight time schedule, we
were not just producing a single coat mono gum but attempting a multiple
polychrome print
Meanwhile, let us not forget to distinguish among dichromate stain,
pigment stain and chemical fog in gum printing -- each sui generis.
Once I have put the dichromate stain to bed,so to speak. Pigment stain will
be the next target
BTW what is sui generis ?
Some strange disease not to be mentioned in polite
society :-)
pete