Iron developers and Amidol and pyrogallol

Terry King (101522.2625@compuserve.com)
Mon, 12 May 1997 05:18:14 -0400

In 1862 in the Photographic News there was the kind of long running
discussion that features on these pages.

It was claimed that while the pundits asserted that there was nothing
better than pyro to develop wet collodion, working photographers used iron
developers almost exclusively as they gave negatives that took far less
time to print out. It was said that iron developers were only suitable for
transpaprencies or that they gave dull grey negatives. Others said that
the greyness only occurred when impure materials were used or the plates
were not washed properly.

Some on this list prefer pyro for developing FP4 for platinum because it
gives the long tonal range and fine gradation that they need for the kind
of platinum prints they wish to make. Others use amidol for the same and I
am sure that they are both right.

Iron developers have faded from the market, I assume, because they give a
negative suitable for printing out rather than developing out or because,
like amidil, they have short shelf lives. I would like to give them a try
for FP4. Unfortunately the recipes for 'iron sulphate' developer I have
appear to be incomplete or overcomplicated to the extent that they appear
to repeat stages unnecessarily.

Has anybody tried iron sulphate developers ? Are we talking about ferric
or ferrous sulphate and is there any need for lead acetate in the mixture
as one recipe claims. Woodbury's encyclopaedia says that Ferrous sulphate
is used in the ferrous oxalate developer but doesnot mention it in that
recipe,presumably because the sulphate was used to make the oaxlate. The
Illiffe Encyclopaedia says that Ammonio Sulphate of Iron was used for
developing wet collodion plates but gives no recipe altyhough it does give
a recipe for a ferric oxalate developer that I am going to try.

Is there anybody here with experience of iron developers with film ?

Terry King