[Leica] Divided D-76

[TTAbrahams@aol.com]

leica-users@mejac.palo-alto.ca.us
Divided D-76
Vancouver, B.C. on February 6, 1998

As I have had several requests for Divided D-76 I send it to you all LUGs in
case more of you are interested. The formula for the Divided D-76 that I have
been using is as below. Its origin goes back to the 50’s sometime and several
chemists have reformulated this version.
Farber suggested the reduction of the Sodium Sulphite. The life of the A bath
is amazing, 2-3 years seems likely. Of course this is somewhat dependent on
how many rolls you do. If you want to make a smaller volume, just divide all
measures by the appropriate factor. Try it out for your own times, I like my
negs rather dense, with lots of details in the shadows. If you are using 120
or 4x5 films you will have to extend the times considerably.
 With the Divided D-76 you can try for a less saturated B-solution, the
50gram/1000 ml is a fully saturated solution, even 30 gram/1000ml should work
although you might have to extend the times somewhat. If you have a chance and
can find Steve Anchells “ The Darkroom Cookbook” I recommend it, great night
time reading too.
Pls let me know how it works out and how you all like it!.
Tom A
TTAbrahams@aol.com

DIVIDED D-76

                                                   A-BATH
Water (50 C.)
3000 ml.
Metol (ELON)
7.8 grams.
Sodium Sulphite
190 grams
Hydroquinone
19 grams
Potassium Bromide
3.8 grams
Water (cold) to
3800 ml

Add a pinch of Sodium Sulphite to the water before you put in the Metol. Allow
each chemical to dissolve completely before adding the next. Let it cool
overnight and check for undissolved particles. If you find these, filter the
solution. I use a Melitta coffee filter for this, but do not reuse this for
coffee later as it tastes really vile!

                                                     B-BATH
The B-bath is mixed fresh for every processing run, it can be reused 2-3 times
if it is done with in a couple of hours.
Water (1/3 of required volume at 50C)                                500 ml
Borax
50 grams per 1000 ml of 
                                                                              
finished volume.
Example: For a Paterson 5 reel tank, use 500 ml of water at 50 C, add 75 grams
of Borax and once this is fairly well dissolved top up with 1000 ml of cold
water. There tends to be small specks of Borax floating around in the
solution, but I have never had a problem with specks on the film.
( I use 20-Mule team Borax for this, seems to work fine and I like the fact
that it is mined in Death Valley, one of my favorite Christmas celebration
places).
                                                     PROCEDURE
Pour the A-bath into the developing tank, agitate vigorously for 30 seconds,
tap the tank to release airbubbles and then agitate for 10 sec/ every 60 sec.
until the time is up. Pour back the A-bath in its designated beaker and pour
in the B-Bath (no wash in between), again initial agitation for 30 sec and
then 5 sec/30 sec or for more moderate contrast 10 sec/60 sec.
Very little development takes place in the A-bath as there is no Alkali
present in it. It only saturates the film, once the B-bath is poured in it
starts developing quickly. Even additional 30 sec over recommended time will
show a marked increase in development. It is CRITICAL that you never
contaminate the A-bath with any B-bath. One drop of B into the A will oxidize
it quickly. Always use separate beakers and mixing paddles. The A-bath will
last a long, long time. It is depleted by absorption into the film (each roll
of 35 mm uses up 6 to 8 ml of A) and when it is down to 1/2 original volume I
usually dump it and mix up a new batch (that represents 3-400 rolls of film).
It will take on a rather disgusting color after a while, but it does not seem
to affect its performance. I tend to filter it every 2 month to remove dust,
filmchips, pieces of felt traps, loose screws from cameras or whatever else
accumulates in it. The original formula called for 100 grams of Sodium
Sulphite per 1000 ml, but I found that if it was reduced to 50 grams the grain
was tighter

The modern films, T-Max etc do not absorb enough developer to work well. It
requires a thick emulsion such as TRI-X, Neopan 1600, Plus-X to really
perform.

                                            PROCESSING TIMES
TRI-X
A-bath 5 min./B-bath 5 min.
Neopan 1600
A-bath 5 min./B-bath 6 min.
Neopan 1600 rated at 800 ASA                                     A-bath 5
min./B-bath 5 min.
PLUS-X at 125 ASA                                                        A-
bath 5 min./B-bath 3-4 min.

The Divided D-76 is not very affected by processing temperature, not much
change if you run it at 68 or 75 Degrees F, although be sure that all the
liquids are at the same temperature, otherwise you might get reticulation of
the emulsion. It is a great developer, TRI-X is easy to print and looks great,
Neopan 1600 rated at 800 looks like a good 125 ASA film and it is cheap too, a
couple of cents per roll!

The fact that there is a limited amount of developer absorbed into the film
also makes it very difficult to overdevelop film, highlights stay nice and
printable and the shadows holds a lot of details too. Almost the perfect
developer!