assessment and I was
still surprised to see the colour cast after three hours as different to
what memory said. I wondered in fact whether the colour had gone on
changing slightly. Without a control it is impossible to say, I have made
a mental note to keep up the drying a little longer bearing in mind that
these diffusion processes don’t appear to have an automatic stop but
just run out of steam.
I was a bit disturbed about the base colour, I have yet to see a good
white, the best so far has been an Ivory colour. One of the first things
to measure I think, as it is going to make a lot of difference to my
difficult shot of the Rhine Falls.
Did I find it easy? The answer must be yes, The only thing that slows
down is the drying, you must dry both sides at the same time or as near as
because there is no stiff base it’s all polyester and chemicals (I
think) so you have to pay attention.
Even so, it is quick and compensation of colour (blessed by the
rainbow) is as quick as you can twist the knobs of your colour head and
rattle off the sums on your calculator and bash your timer.
P.S. I felt I might as
well finish the investigation and colour compensate so I popped along to
buy a further 10 sheets this would have cost me £12.50 or so I felt this
was too much to pay to prove a principle particularly as it is unlikely I
will be able to afford to use the process, so did not go further.
Member Mr. Frank White
of Area 13 sends some comments on points raised from the July issue of the
Newsletter.
Firstly the matter of the Glacial Acetic Acid, Yes it is difficult to
obtain and can be dangerous to store and use When I started to process
negatives and prints, my parents would not permit it’s presence in the
house. So the alternative was used 3 to 5% solution of Potassium
metabisulphite or Sodium metabisulphite.
I would also remind members that Johnson of Hendon used to supply the
powder in tins sufficient to make 80oz, and during the war, small tins
sufficient for 40oz of solution were packed for use by the R. A. F. &
Navy photographic units. Hence I feel that any discontent over
none-availability is purely imaginary, especially as Paterson Products are
available at R.R. prices at Photo stores and their Stop bath is Marketed
as Acustop at about £3.50 for 500m1.
Secondly
E.6. Developing Process Page 3 (Ron Croad’s formula).
Sodium Sulphite the second constituent, can you confirm that this
is Anhydrous.
(Corrections in this issue, Frank.).
Under Bleach. Disodium Hydrogen Phosphate. Are we to assume
that this is 12H20 ? (Both are Crystaline type).
And finally, can the author state with what films this process has been
used. Ron comments Barfen CRX100 (Fuji) and just recently 3M 400 ASA.
While getting excellent results from the Barfen he got poor results from
the 3M.
The piece about Citrazinic Acid, Genochrome and ACT7, for those who
don’t why Citrazinic Acid is employed refer them to Jacobson page 378
& 379, 18th edition. It is to prevent excessive contrast of the dye
image. From, I believe L. F. A. Mason’s book. About 1.5 gms, litre, a
change will control green and magenta direction as well as overall density
of the transparency. Depending on concentration the tendency is to green
(dense) to thin magenta as a result. The result is bourn out in the text.
So I suggest it is back to the drawing board.
To update this, I have been reliably informed that ‘Genochrome’ is
no longer being manufactured by M & B and I understand when stocks are
exhausted, will no longer be available.
The remark about, ACT 7 not being available is wrong. I purchased some
from Hogg’s Labs in Oct. 1981 and Patrick Fraser purchased some in April
this year.
It is listed in BDH chemical catalogue of 1983 pages 28 and 200 as Di,
Ethyl Paraphenylene, Diamine Sulphate. (ACTIVOL &). Alternative name
=, AMINO-N-N- DIETHYLANILINE SULPHATE. C. J. Jacobson lists
the above name. as
‘ACTIVOL 7’.
Those wishing to purchase should quote the last name 4.A.N.N.D.S. and
mention the manufacturers as Koch - Light and request Hogg’s Labs for a
proforms invoice. The price is circa £3.25/25gms.