Re: [Leica] Re: Divided development (long)

[D Khong <dkhong@pacific.net.sg>]

Johnny Deadman wrote:

>Split Developers
>================
>
>Wow, man, this it technical stuff and gets confusing real quickly, but stick
>with the program, cause it's one of the great hidden joys of b&w
>photography, especially the kind of stuff people do with their Leicas. I was
>introduced to it by Boston documentarian Roswell Angier (anyone here know
>him?) when I lived in his attic for six months.
>
>Essentially it allows you to expose a roll under vastly different lighting
>conditions, even at different speeds, but so long as you have looked after
>the shadow exposure, you should end up with not just printable, but
>beautiful negatives, with long tonal scale, fine grain, and no blocked
>highlights.
>
>I will outline the process here, but there are better references in THE
>FOCAL ENCYCLOPAEDIA OF PHOTOGRAPHY, THE DARKROOM COOKBOOK, THE PRACTICAL
>ZONE SYSTEM, BEYOND THE ZONE SYSTEM and ANSEL ADAMS: THE NEGATIVE.  There
>are also some resources on the web at www.heylloyd.com. Finally, it is a
>continual source of discussion on rec.photo.darkroom, and a search for
>'split d-76' or 'divided d-76' or 'divided d-23' etc should turn up articles
>by me and others discussing the process.
>
>Skip down to the bottom of this post for details of chemicals, times, films
>etc.
>
>The basic premise is: the film goes through two development baths. The first
>contains either (1) regular developer (D-23 and D-76 are faves) or (2) a
>modified developer (such as D-76D) which has no alkali (accelerator) in the
>solution.
>
>In any case, time in the first bath is restricted to (usually) 2-4 minutes.
>Whatever development DOES take place in this bath is restricted so that
>highlights develop to just about where you want them.
>
>Now the clever bit. The film is transferred, without washing, to a bath of
>alkali such as sodium carbonate, kodalk (sodium metaborate) or borax, and
>left there without agitation for 3-5 minutes.
>
>What happens in this bath is a function of the developer which has adsorbed
>into the film emulsion and which is activated by the alkali. In highlight
>areas, the developer quickly exhausts, and development essentially stops. In
>shadow areas, however, the developer exhausts much more slowly and
>development continues, increasing the density of shadow detail while not
>blocking up the highlights.
>
>The film is then stopped, fixed and washed as normal.
>
>Ansel Adams claims that with D-23 this results in the equivalent of an N-2
>contraction. If this were all that happened, it would not be interesting,
>but - especially with a developer like D-76 - the actual effect is a more
>interesting.
>
>You essentially (ideally) end up with a negative which has very good LOCAL
>contrast - ie within particular areas of tonality - but a compressed tonal
>scale overall, which one hopes is matched more closely to your paper du
>choix. The upshot is they are easy to print, and have beautiful greys, and
>retain detail in highlights that would burn out in another developer. If
>your idea of a nice print is that HCB Zone 5 look, this is a process you
>should try. Prints from these negs have a very particular, mellifluous, look
>which you can spot a mile off once you've seen it once.
>
>The big difference from standard N-1 or N-2 contractions is precisely in the
>shadow values, which have greater density and tonality. It is almost as if
>you give the highlights an N-2 development and the shadows an N development.
>
>Overall highlight density can be controlled by the time in the first bath
>and the choice of developer. Overall contrast can be most easily controlled
>by choice of developer. Shadow support is a function of time in the second
>bath, but improvements after 3 minutes are marginal (you can leave it in as
>long as you like).
>
>There are pros and cons to this process.
>
>Pros
>====
>
>1)    Very simple and quick
>2)    Not heavily time or temperature dependent
>3)    Does not generally require a big reduction in film speed. Some people
>claim a gain in film speed of up to a stop. I lose half a stop, personally.
>4)    Fine grain
>5)    Cheap
>6)    Very printable negatives with fine tonal gradations
>7)    No blocked highlights
>8)    You can develop different films in the same batch
>
>Cons
>====
>
>1)    You need to run some tests to get the best out of it
>2)    You may (or may not) need to mix your own chemicals (but it's bloody
>easy)
>3)    Done badly, you may end up with horribly flat negs
>4)    Pretty unforgiving of underexposure
>5)    Doesn't work well with thin-emulsion films such as Delta or T-max.
>Basically, it's Tri-X, chaps -- but the results can be amazing.
>6)    If you agitate too enthusiastically in the first bath you end up with
>horrid drag marks around the perforations. Gently does it!
>7)    Fog levels may be high (though I have not found this). However, Ansel
>says you can simply 'print through' this.
>
>To me the pros far outweigh the cons, but you really have to suck it and
>see. It's worth sticking with it for a few rolls, because you need to get a
>feel for the way the various parameters interact, which is NOT necessarily
>the way ordinary developers work. The key, for me, is finding your Zone III
>shadows and exposing for them without cheating. Sometimes this means
>shooting 1/125 at f8 in blazing sunshine. You just have to grit your teeth
>and trust your meter! The highlights genuinely do take care of themselves.
>
>The single greatest plus is getting a whole roll from a manual camera in
>changing light when you couldn't keep pulling out the Sekonic - and they are
>all printable (and readable from the contact sheet). To me the 'look'
>resembles XP-1, with somewhat crisper grain.
>
>My times/temps/speeds are the following (all with Tri-X rated 320, all @
>68F)
>
>SPLIT D-76
>==========
>Stock D-76             3 mins*     5s/30s gentle agitation
>1.5% Kodalk            3 mins      No agitation
>
>*increased to 4 mins if whole roll shot on a dull day, maybe pulled back to
>21/2 or even 2 if the light was blazing.
>
>SPLIT D-23
>==========
>
>Stock D-23             4 mins      5s/30s gentle agitation
>1.5% Kodalk            3 mins      No agitation
>
>Of these two processes, I prefer the first, which gives negs with more
>'snap'. However, if you are shooting flash at night or in Californian
>sunshine, the second may be a help.
>
>D-23 is not commercially available - you have to make it up yourself - but
>frankly it's no harder than mixing D-76 from the tin. It only has two
>components - Metol and Sulfite - both of which are cheap and widely
>available. D-23 is a fine developer in its own right, and worth playing
>with. In particular, D-23 can be stunning with TMAX -- no more blocked
>highlights!
>
>As for 'true' split D-76 (D-76D, which you also have to mix yourself), I
>have no experience with it, but others claim very good results, something
>like a combination of the above two processes.
>
>I have probably made some crass errors in the above, but it reflects my own
>experience. Your mileage may vary.
>
>--
>Johnny Deadman
>
>"There is no need for the writer to eat a whole sheep to be able to tell you
>what mutton tastes like. It is enough if he eats a cutlet. But he should do
>that" - Somerset Maugham
>

Johnny,

GASP!  This thesis has my jaw hanging half a mile from my
temporo-mandibular joint.  Yesiree.... don't we have another darkroom guru
in this illustrious group.   

What you have not told us yet is whether you drink single malt booze. ;-)

Dan K.
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                  Humility is the forerunner of Wisdom
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