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CHEMICALS: BER-01 Lith

This unique developer was conceived specially for the lith printing technique. Optimum working solutions can be mixed for all "lith-capable" papers using the two concentrates and the two additives (sulphite and bromide).
"Lith-capable" refers to all chlorobromide emulsions without incorporated development accelerators such as phenidone. BERGGER papers are all "clean" in this regard. When experimenting with other papers, following test is recommended: place a few drops of Solution B on a strip of paper under daylight conditions. If the paper shows no change after two to three minutes, or no more than traces of pink or brown colour, then it is "clean" or only contains hydroquinone and is worth a try. In cases where the paper shows definite blacks, particularly when these appear instantly, a development accelerator is present, and one can give up the attempt right away, or try to evade the problem through extensive pre-soaking.
The mixtures and times given in the table are merely starting recommendations. Development times resulting from dilutions and exposure were compiled using negatives with medium contrast and a developer temperature of 20°C. Raising the temperature to 24°C or more considerably accelerates the entire development process, without having any negative effects on the result.

Preparation of the working solution
Example given on BERGGER Variable CB. Dilution : 1+10
Requirements: 50ml of solution A plus 50ml of solution B = 100ml of developer x10=1000ml.
To obtain favourite picture tone 10ml of Bromide solution is needed.
The concentrate and additives should firstly be mixed and stirred well with 800ml of water and afterwards be diluted to the amount of 1000ml. You can work with 800ml . 200ml of this solution should be filled in a bottle or measure for later regeneration.
In case the exposure time for conventional processing is not known, inexperienced users should determine the "normal exposure time" with their preferred developer through tests, for which it makes sense ( because of reciprocity failures ) to use the highest aperture number possible. The exposure time thus determined remains constant, the aperture for this example is opened by 3 full f/stops. The expected development time is around 8 minutes.
The prints should be agitated continuously during the entire development time. The print should not under any circumstances be allowed to float on the surface where "dry" spots could form. Development by sight must be used with this procedure, at least towards the end! To summarize: emulsion up, don't worry about fogging and agitate continuously. Nothing will appear or nothing seems to be happening at first.

With few exceptions, it takes between two and four minutes for the first sign of the image to emerge. In cases of high dilutions and high bromide content, image completion will be extremely slowed down. This is absolutely necessary for achieving a tonal value differentiation in the highlights when there is a lot of color (yellow-brown, ochre, red-brown, pink). After the first half of the anticipated development time, the print should not yet show any definite light/shadow differentiation; the darker areas should not under any circumstances be emerging too quickly, because then the "lith belt" (meaning the area of black tones lacking all detail) will be too wide on the finished print.
The print will seem flat and weak right up until just before the end. Then the semiquinone kicks in and the blacks start to appear, spreading out from the deepest shadow areas, modulating the image as they go: first hesitantly, then ever more quickly from one zone to the next. It takes practice before one learns to recognize the correct instant for interruption. A few seconds one way or the other makes the difference between garbage pail and gallery wall !
Finished? Out of the developer and fast into the Stop bath! Agitate quickly and well!
Never let the excess developer drain off the print, though this will mean that you will need to renew the stop bath more often than usual.
As a rule, the following applies:

The more light during enlarging, the warmer the print tones in the highlights and middle areas and the softer the gradation. If however the light is increased, (at least in cases where the exposure time increases to more than half an f/stop), then the developer must be adjusted through either a greater dilution or an increased bromide content, because otherwise the picture would come up too quickly.
In extreme cases the highlights too would already get darker before the "infectious development" could begin.
The longer the start of the "infectious development" is delayed, the more intense the effect will be.

Now those who are impatient to begin can start right away.
Systematic workers desiring greater knowledge should read on before starting.

An understanding of the action mechanism is an absolute requirement for fine calibration and optimum regeneration of our developer. A detailed description of the complex processes would exceed the framework of this introduction (for more information, we recommend Tim Rudmans, The Master Photographers Lith Printing Course ISBN 1-902538-02-1), so here only the most important things in brief. The trigger for the "infectious development" is the formation of semiquinone during the development process. Semiquinone is an intermediate oxidation product of the development substance hydroquinone, which is normally "picked up" by the antioxidants (such as sodium sulphite) contained in the developer. For this reason, lith developers cannot contain more than traces of free sulphite, which unfortunately has adverse effects upon the working life of the solution. The rapid formation of semiquinone in this developer is enhanced by an additive. For that reason, the often-recommended "inoculation" (addition of used, heavily-oxidized solution) or "maturing" (starting semiquinone production by developing a strip of exposed paper) of working solutions is not necessarily required; even the first print will be dependably "lithed". These methods are nevertheless useful for stabilizing the developer; otherwise one cannot count on reproducible results until after the third print has gone through. Barriers of different levels of effectiveness can be constructed to prevent the semiquinone from kicking in too soon in the development process. In addition to other restrainers, generally bromide is used in this regard. It is not able to begin to be effective upon the partially-developed silver molecules until the semiquinone content of the developer has exceeded the predetermined threshold level of the user's choice. Then, however, its effect is very sudden, equaling in its effect a second, superadditive developer substance. Lith developers which are severely exhausted, particularly those with extremely high dilutions, reach the limits of their buffering capacity through acidic oxidation products. Sulphite is used up, alkalinity falls off, which leads to the situation where highlights need more light than the semiquinone allows. An additional difficulty is the increasing amount of bromide released from the emulsion. For that reason, to ensure consistent print results, regular regeneration is required, at least with dilutions greater than 1+15. Regeneration type and quantity are also depend on the paper used. Normally, regeneration with a working solution of the same dilution (with either zero or reduced bromide additive) is sufficient. More on this below.

Addition
+ Solution A: harder, more colorful, grainier, slower, shorter working life
+ Solution B: softer, less colorful, faster, longer working life
+ Bromide: delays the onset of the lith effect, requires more light
+ Sulphite: antioxidant and darkening reducer, careful dosages against overlarge grain

Working life: general specifications regarding lith developer working solutions are total nonsense! The following factors have an effect upon working life:
1. Degree of dilution
2. Composition: relationship A:B and additives such as sodium sulphite
3. Amount of use: fresh ,- used ,- used up
4. Oxidation surface: bottle filled to the top or tray filled to the depth of a finger
5. Developer quantity per oxidation surface
6. Regeneration

A visual point of reference for the condition of the working solution is the color. When freshly mixed, it is clear; as it is used it becomes yellowish to amber in color. It must be regenerated no later than this point. When it reaches the point of being reddish-brown, monitoring is difficult; dark red means it's all over! Solutions that have been somewhat used (yellow) can be stored for a few days in filled, tightly-closed bottles.

Shelf life of the Concentrates:
A full/half-full bottles 24/12 months after date of manufacture
B full or partially-full bottles 24 months after date of manufacture (see batch number)
C sodium sulphite solution: full/half-full bottles: 8/2 months after date of manufacture.
D potassium bromide solution unlimited

Regeneration:
In the interest of consistent results, regeneration should be carried out regularly, starting with the third to the fifth print per liter. The following types of regeneration are possible, depending on the paper used, as non-combinable alternatives:
1. using working solution of the same dilution (using half as much bromide as in the initial solution), either with 10% of the initial quantity on a regular basis or more on an irregular basis (during the process if needed, but then gradually adding it, accompanied by vigorous agitation)
2. with diluted Solution B, in order to maintain stable pH value (in case the Lith Point moves downward too much) -- don't overdo it, start with small quantities and watch effects!
3. with Solution C: usually 2-5 ml is sufficient; considerable larger quantities are necessary with some papers in order to avoid pepper corn-size, grain and "black dots". With Sterling/Fotospeed, for example, the quantities listed in the table are sufficient as a rule. With papers which are extremely susceptible to "black dots", such as MACO exp R, sulphite prophylaxis should be instituted.

Tips and Tricks

Operating temperature: The normal temperature, as always, is 20°C. The developer temperature can be raised to 25-28°C to shorten the process times. The speed savings when going from 20°C to 25°C is 40%. Bromide-rich solutions can be taken up over 25°C, although one must remember that elevating the temperature speeds up all chemical processes, meaning oxidation as well!
Formaldehyde, which usually appears in lith developers, has been dispensed with in this formula. That means that there are no unpleasant odors or emission-related health risks to be concerned about, even at high temperatures.

Two-bath development:
Often the only solution for highlight definition + lith black with high-contrast negatives and papers with high levels of silver bromide.
Example: first developer with high bromide content (highlights hold, shadow areas develop without lithing), changing into second developer without bromide or sulphite, even perhaps with a slight excess of Solution A (more than 30-60 seconds is rarely necessary).

Toning: Lith prints are extremely responsive to toning. Selenium or gold tonings (or combinations of both) are even often indispensable.
It is undoubtedly selenium toner that offers the greatest variety of possibilities. Depending upon dilution and exposure time, one can just enhance the shadows or change their tonal color, or one can alter all the tonal values in their print color. Some papers, when lithed with a lot of bromide, show no maximum black. Selenium performs miracles with these, hard and fast (1+3 to 1+9, 10-30 seconds!).

Hardening: Some papers (particularly those with matte surfaces and factory-fresh emulsions) should be hardened before toning in aggressive baths such as cyan, sulfur or selenium (less than 1+15) when subjected to development times over 8 minutes, in order to avoid coloring in the picture highlights. Gelatine hardening is possible as a general rule at all stages of the processing procedure:
1. Hardening before development (alkali hardener): the disadvantage is the effort involved -- every print requires an additional three to four minutes of additional processing time
2. Hardening additive in stop or fixing bath: advantage: standard-issue hardening additives on the market; disadvantage: increased water use through considerable prolongation of the washing time
3. Hardening after fixing and brief washing with one of the well-known acid solutions, or with our special lith hardener. Disadvantage: extensive washing must take place once again before selenium toning, or the acidic paper felt must be neutralized in a washing aid

What else?
The OFF switch for the lith effect
If one only wants the glowing colorfulness and finds the lith effect as an apparently necessary evil, then just switch it off! There are two alternative methods available for doing this:
1. Tiny quantities of any given paper developer: because, all the developers to be found on the market, except for a very few exceptions, contain at least two developer substances, the hydroquinone in the lith developer reacts superadditively with at least one additional developer substance and "lithing" is no longer possible. The print color shifts more or less strongly in the direction of green.
2. Large quantity of sodium sulphite: the precisely correct quantity, depending upon the paper being used, falls between 40% and 200% of the Solution A quantity.
Beautiful brown tones can be created with warm toned papers in particular.

Example : BERGGER Prestige: Dilution 1+8 tone brown and 1+15 tone reddish brown

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