Re: Gum Arabic and Baum

Pascal MIELE (pascal.miele@wanadoo.fr)
Sat, 13 Jul 1996 19:52:08 +0200

Jeff Stanfordl wrote:
>The Hygrometer is for measuring humidity.
>The Hydrometer is for Baume or Specific Gravity.

In french
Hygrometer is hygrometre
Hydrometer is densimetre (measure liquid density)
no confusion... speak french !

Judy wrote:
> It does occur to me to wonder if the hydr/hygrometer is calibrated alon=
g
> some absolute scale, because I suspect discrepancies between instrument=
s,
> or by elevation, or air pressure, or whatever, not to mention latitude =
&
> longitude. How accurate is it? How much liquid do you need to float i=
t?

Density change with temperature, a good densimeter is calibrated for
a specific temp. But any precise measure (length, weigth...) is correct
only with precise operating conditions.

In the french magazine "LE PHOTOGRAPHE" the sensitomertry tests has a
famous "conditions op=E9ratoires":

for the FUJICOLOR SUPER G PLUS 800 test (not a true alt-process-film):

CONDITIONS OPERATOIRES:
QUINCAILLERIE
MATERIEL D'EXPOSITION
Sensitographe Kodak X6, Filtres MTO Neutravex Intervex, Mires
Iconel, Poste ponctuel Vannier-Photelec, Nikon F2 Titan, Flash
Broncolor
MATERIEL DE TRAITEMENT
Machine transfert =E0 programation, pilotage sensitometrique.
MATERIEL DE TIRAGE
Tireuse Kodak 8 MC, D=E9veloppeuse Agfa Pro, Papier Fuji Super FA=
III
MATERIEL DE MESURE
Densitometre Macbeth 924 TR AM. 1224 TR/AM et X-Rite 820.
Spectrophotometre Hewlett-Packard 8452, Spectrocolorimetre Minolt=
a
CM 1000, radiometre Tektronix J16 et Spectron, Photometres Minolt=
a.
MATERIEL DE TRAITEMENT DES INFORMATIONS
PC 486 Hewlett-Packard ES12, Apple Quadra 900 et Mac IIx, Table
Graftech.
EMULSIONS TESTEES
Super G Plus 800 n=B0 L51-504
Comparatif: Super G 800 n=B0M10-36, Ektar 1000 n=B0013
MORAL DES TROUPES
Salade folle
Homard grill=E9
Corbeille de sorbets
Sauvignon Saint-Bris 1994

This is a very complete "Conditions operatoires"

Jeff Stanfordl wrote:
>The chemical supply company where I bought mine has at least 10 differen=
t
>kinds with various scales. Mine needs at least 180ml liquid to float wel=
l.

In the Prolabo documentation (not under my hand) they have maybe 50 model=
s
differents scales, differents precisions (differents prices !)

Pascal MIELE Atelier photographique MIELE
------------ 8 place P. et M. CURIE
64150 MOURENX FRANCE