"Thor Lancelot Simon" wrote in message
...
In article
,
Lew wrote:
The instruction sheets for the two papers I'll be trying
(Arista & Forte)
recommend Dektol, why not a warm tone developer (like Agfa
120)?

Dektol will give a warm tone tending towards green, with
the Forte paper
at least and probably with some others. A "warm tone"
developer will give
a warm tone tending towards yellow-brown. Either can be
quite nice,
depending on what you're aiming for. Some photographers
consider the
greenish tone resulting from using a "cold tone" developer
with a "warm
tone" paper to be ugly, particularly for certain subjects;
personally,
I like it a lot for night shots of architecture, and for
certain other
things, but I usually find it unwelcome for portraits.

Ektaflo Type 2 is a nice developer to keep handy for use
with warm
tone papers. It is a convenient liquid formula which
gives results
that are not so far towards brown as some other
developers, but not
green as Dektol can be. It is basically the same as Kodak
Selectol,
which is no longer available, so you can really fine-tune
image color
and contrast by either substituting it with Selectol-Soft
(which gives
less contrast, and a _very very_ slightly warmer image) or
mixing it
with Dektol working solution (which gives both higher
contrast and a
shift in image color depending how much of each is used in
the mix).

--
Thor Lancelot Simon


Ektaflo Type-2 is a liquid similar to the discontinued
Ektonol. Ektonol was advertised as not containing carbonate.
Ektonol had a mixtuure of Borax and hydroxide, which become
Kodalk in solution. Kodak claimed this reduced the chances
of staining when toning but I've never seen an explanation
of this claim or ever had a problem with staining which
could be traced to the developer.
The main difference between cold, normal, and warm tone
developers is their activity. In general, warm tone
developers have less carbonate. Agfa/Ansco 120 is different
because it has only Metol as the developing agent. This is
similar to Kodak Selectol Soft.
Some developing agents, notably Glycin, and Hydroquinone
when used alone, tend toward warmer tones. Increasing the
amount of Bromide will also shift tones toward yellow.
Potassium salts are supposed to be somewhat different
than Sodium in photographic activity but I've never seen any
sort of scientific measurment of this. For the most part
they are interchangible. While Agfa liked to use Potassium
salts in its packaged formulas the published ones have
mostly sodium salts. Agfa evidently obtained potassium salts
cheaply as a by-product of some manufacturing process. Here
are some formulae for comparison:

Agfa 120 Soft Working Paper Developer
Water (at 125F or 52C) 750.0 ml
Metol 12.5 grams
Sodium Sulfite, dessicated 36.0 grams
Sodium Carbonate, monohydrated 36.0 grams
Potassium Bromide 1.8 grams
Water to make 1.0 liter

For use dilute 1 part stock with 2 parts water.

Agfa 125 Standard Paper Developer
Water (at 125F or 52C) 750.0 ml
Metol 3.0 grams
Sodium Sulfite, dessicated 44.0 grams
Hydroquinone 12.0 grams
Sodium Carbonate, monohydrated 65.0 grams
Potassium Bromide 2.0 grams
Water to make 1.0 liter

For use dilute 1 part stock to 2 parts water.

Agfa 106 Warm Tone Paper Developer
Water (at 125F or 52C) 750.0 ml
Metol 0.7 grams
Sodium Sulfite, dessicated 11.5 grams
Hydroquinone 3.5 grams
Sodium Carbonate, monohydrated 10.5 grams
Potassium Bromide 2.4 grams
Water to make 1.0 liter

Do not dilute for use.

Agfa 103 Blue-Black Paper Developer
Water (at 125F or 52C) 750.0 ml
Metol 3.5 grams
Sodium Sulfite, dessicated 45.0 grams
Hydroquinone 11.5 grams
Sodium Carbonate, monohydrated 78.0 grams
Potassium Bromide 1.2 grams
Water to make 1.0 liter

For use dilute one part stock with two parts water.

Agfa 120 is equivalent to Kodak Selectol Soft (no published
formula)
Agfa 125 is equivalent to Kodak D-72/Dektol
Agfa 106 is equivalent to Kodak D-52/Selectol but at half
strength i.e., equivalent to the developer diluted one part
stock to one part water.
Agfa 103 is equivalent to Kodak D-73.

An example of a Glycin warm tone developer is Agfa 115

Agfa 115 Glycin-Hydroquinone Developer for Warm Tones
Water (at 125F or 52C) 750.0 ml
Sodium Sulfite, dessicated 90.0 grams
Sodium Carbonate, monohydrated 150.0 ml
Glycin 30.0 grams
Hydroquinone 9.5 grams
Potassium Bromide 4.0 grams
Water to make 1.0 liter

For use dilute 1 part stock with 3 parts water.
This developer yields warm tones with normal paper exposure
times.

Note that the amount of Potassium Bromide in many print
developers, notabl the Dektol types, is minimal, typically
around 2 grams/liter of stock. This can be increased very
considerably, up to around 12 grams per liter, with
consequent warming of the image tone. There will be some
loss of paper speed as the amount is increased.

For convenience I've copied these formulas from the 1944
edition of the _Photo Lab Index_, however, I have the
original Agfa and Ansco formula booklets and have checked
the formulas with them.
All of the publications for the U.S. market specify sodium
salts for the carbonate and sulfite. However, in my German
edition Potassium salts are indicated in some formulas. I
think this is more a matter of what was available than the
photographic effect.


--
---
Richard Knoppow
Los Angeles, CA, USA