Auteur: Claude Eichel
Date: 06-04-2006 20:32
Bonsoir,
j'avais testé le D23 en deux bains, puis le HC110 en deux bains (et deux dilutions différentes ; le tout en jobo)) mais très honnêtement je n'ai pas vu de meilleurs résultats qu'avec le HC110 ou le pyrocat. Ce dernier est suffisemment compensateur pour ma façon d'opérer. Quand à la température on doit pouvoir travailler à des températures supérieures à 20° en adaptant les temps. Le HC110 en deux dilutions me semblerait plus prometteur en terme de compensation.
je me permet de faire un copier coller d'une page sur le sujet que j'avais sauvegardée mais dont je ne trouve plus l'url
Vec toutes lmes excuses envers l'auteur
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Split Negative Developing Technique No.1
For traditional B&W films only…. Not for Chromgenics…. Shoot film a one half ISO (ASA)… that is, shoot ASA 400 film at 200, 125 at 64 and so on.
Note: Mix from raw, out of the bottle HC110….. very thick and more like honey. (or Alta Gamma +)
Mix two batches of HC 110. One batch at 1:31 (Alta Gamma + is at 1:12)
• Next HC 110 batch at 1:180 (Alta Gamma + at 1:99)
• Pre-soak in wetting agent for 3 min and save the wetting agent.
• First batch (1:31) for 2mins @ 70º …. agitate 90º flips for first 30sec, then two flips every 30 secs
• Dump first developer
• Second batch (1:180) for 10 min (also @ 70º) …. agitate 90º flips for first 30sec the one 90º flip every 15 secs
• Dump second developer and pour in saved pre-wash and dump it right out.
• Fix and wash normally.
•
• If you use Kodak's Stock solution mixture of HC 110, then the first batch is 1:3 and the second 1:45
What you have here is a strong developer to start the highlight (dense) areas of the negative and then a shift to a compensating developer to work on the shadow areas of the negative. What you will get is a very long scale negative with lots of shadow detail.
Using a spot meter, place shadows on Zone 3. Over expose and under develop. The old rule.
If you have film that was shot at full ASA, time in Dev A should be about 2 ½ to 3 minutes and time in Dev B should be 11 to 12 mins. All else remains the same.
Split Negative Developing Technique No.2
In this type we use the old D-23 and Borax. This really is several folks combinations of "divided development"
First, D-23 is made as follows:
D-23 The Old Standard (And the Windisch Formula)… First, some stuff about D23 used straight…. That is, with no second deveoper
Chemical D23
Metol 7.5 gms
Sodium sulfite 100 gms
Water to make 1 liter
D-23 is perhaps the simplest of all negative developers. (See formula above) It consists of Metol and Sodium sulfite. Easy stuff. Generally, it is used straight, that is, right out of the bottle. However, it can be made into a compensating developer (meaning fast and quick work on the shadow areas and slower on the highlights….. thus causing better shadow detail and no blocking up of the highlight areas) by using it 1:1 or better yet, 1:3 …. Of course, you have to mix this stuff yourself. It mixes at 125º F and must cool before you use it. (Note: D23 is available from Photographer's Formulary)
Mixing instructions are simple. First add a pinch of the Sodium sulfite to the water….. this will keep the metol from oxidizing too fast and make it easier to go into solution. Next, mix the Metol and finally the bulk of the sodium sulfite.
It is also useful to add about 5ml/liter of EDTA to the solution to prevent Bromide burnout along the top and bottom edges of the film, especially if you are using stainless steel reels. Just works better!
Here's a table showing times for some Ilford and Kodak films….. all at 68º F (change 4%/deg)
Film Type Straight 1:1 1:3
Ilford D 100 7 10 15.5
D 400 7 10.5 16.5
Pan F 6.5 8.5 15
FP4+ 6 8 13
HP5+ 7.5 13 20
Kodak TM 100 8 11 16
Plus X 7 16 13
TM 400 7 10 15
TriX 7.5 13 20
TM 3200 11 16 NR
Since D-23 is an inherently low contrast developer, increases in development time are about 50% +/- for +/- 1 stop of contrast, as opposed to the usual 27%.
If you use D-23 straight, after 2 rolls, increase time by 10% for each more 2 rolls done.
Water Bath Development: D-23 works well as a two bath developer. If you use water, there are several techniques. Ansel Adams used 5 mins in D-23, 5 in plain water, and another 5 in D-23, moving back and forth….. small or deep tank.
BORAX TWO BATH
We can develop first in straight D-23 and then in a 4% solution of Borax (sodium tetraborate) or in water. Sodium tetraborate works better, since it is much more alkaline than water.
First develop slow to medium (25 to 400 ISO… all shot at ½ the ISO) speed films for 5 mins in D-23 then 5 mins in (about) 4% solution of sodium tetraborate. (Note: Sodium tetraborate is really 20 Mule Team Laundry Additive, available at grocery stores!)
Mix the Borax solution like this….
Water at 70º 1 liter
Sodium Tetraborate 40 ml
I always start with a small amount of water at 120 deg F to get the borax to go in solution and then fill with cold water to the volume I want.
You will have to make some tests to see what combination of D-23 and/or sodium tetraborate or water will work best for you. But be assured you will get superb negatives when you get it worked out. D-23 will produce negatives that are easy to print and will require less burning and dodging than most other developers, with the possible exception of PMK.
Lately, it has come to my attention that there are several variants of this process, all related to the alkalai second bath…..goes like this:
• High Contrast Use 8% solution of sodium carbonate (Arm & Hammer Washing Soda…. Grocery store stuff, again…. It is really decahydrated sodium carbonate
• Low Contast Use 4% solution of sodium tetraborate
• Med Contrast Use 4% solution of sodium metaborate (Photographer's Formulary
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Cordialement
Ce
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