From: Christina Z. Anderson (firstname.lastname@example.org)
Date: 07/01/03-05:18:54 PM Z
Chrome alum: 4g a tsp.
I get the same av weight for both pot and am di--surprises me because
pot is very powdery and am is more crystallized, but that's what I found. (I
get with my tsp 6.5g av, but the Darkroom Ckbk gives a weight of 7.9; I
would trust their figure far more than my tupperware teaspoons.)
It is vital, if you are going to really get into alt processes, to get
a digital scale. They are not too expensive; try TriEss Sciences
(800.274.6910 www.tri-esssciences.com) and see if they have a reasonable
one. Mine was around $80 and I use it all the time. I could have just been
lucky when I bought it, though, as the place was no longer gonna carry them.
But I only use tsp amounts when it is not critical if you are off a
gram or two or 5.
----- Original Message -----
From: "Devra Goldberg" <email@example.com>
Sent: Tuesday, July 01, 2003 3:39 PM
Subject: Re: a measuring question
> thanks, wayne! right now, i'm specifically looking
> for chrome alum, but i'm also interested in the other
> cyanotype II chemicals--ammonium iron oxalate and
> ammonium dichromate, i believe.
> --- Wayne Bowdish <firstname.lastname@example.org> wrote:
> > Philippe is right - I have my copy of the 'Cookbook'
> > in front of me and it has gram/teaspoon equivalents
> > for about 30 chemicals.
> > Info has also been posted to the list in years gone
> > by, some of which I've noted saved.
> > The equivalents I use mostly are (don't remember who
> > posted this but thanks):
> > Approximate Weight to Volume Ratios of a Few
> > Chemicals
> > (how many grams in tablespoons or teaspoons of dry
> > chemicals)
> > Chemical (in grams) 1 tbsp 1/2 tbsp 1 tsp 1/2
> > tsp 1/4 tsp 1/8 tsp
> > ferric ammonium citrate 12.5g 6.2 4.1 2.0
> > 1.0 0.50
> > potassium dichromate 22.0g 11.5 7.9 4.1
> > 2.2 1.1
> > potassium ferricyanide 15.5g 8.0 5.5 2.8
> > 1.5 0.8
> > silver nitrate 41.0g 20.7 13.8 7.0
> > 3.6 1.8
> > sodium thiosulfate 18.0g 9.0 6.0 3.0
> > 1.5 0.75
> > tartaric acid 12.6g 6.3 4.2 2.1
> > 1.1 0.5
> > Note that you will often find different values
> > quoted. I assume that there are differences because
> > of moisture content, manufacturing technique,
> > crystal size and who-knows what else. For example,
> > potassium ferricyanide is quoted as 15.5 grams per
> > tablespoon above, 16 grams per tbsp in the
> > 'Cookbook' and when I weighed mine a couple of
> > months ago to check some course notes I was
> > preparing came up with 16.4 grams per tbsp.
> > Devra
> > If there is a specific substance you need to know
> > about let me know and I'll check the 'Cookbook'
> > ----- Original Message -----
> > From: "Philippe Ayral" <email@example.com>
> > To: <firstname.lastname@example.org>
> > Sent: Tuesday, July 01, 2003 11:28 AM
> > Subject: Re: a measuring question
> > > If my memory is still good there is some
> > equivalent at the end of:
> > > "Darkroom CookBook"
> > >
> > >
> > >
> > >
> > > --
> > > Philippe Ayral
> > > http://perso.club-internet.fr/payral
> > > http://www.focale.ch
> > >
> > >
> Do you Yahoo!?
> SBC Yahoo! DSL - Now only $29.95 per month!
This archive was generated by hypermail 2.1.5 : 08/07/03-03:34:49 PM Z CST