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Photography. Choice Of A Developer |
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Photography. Choice Of A Developer |
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This section is from the book "Amateur Work Magazine Vol4". Also available from Amazon: Amateur Work.
John Everard
The amateur photographer, still on the threshold of our fascinating art-science, often finds himself in a predicament when necessity demands that he should purchase a fresh supply of developer, the supply included in his newly acquired outfit being exhausted. Should he be unacquainted with a seasoned photographer from whom to seek advice, he will probably rely on the dealer's recommendation, and, although the assistance given by the latter gentleman is often of considerable value, the vendor of the developer cannot be expected to burden himself with the cares of the newly-born amateur. Therefore, it very often happens that instead of obtaining a developer of easy manipulation, and possessing these possibilities of control so essential to a beginner, he is hurried towards failure by using an unsuitable developer - unsuitable because in his embryonic stages he lacks the technical knowledge required to use that particular developer to the best advantage. It is said that "patience is a virtue " in all occupations, but so few pursuits require so much endurance as photography, particularly the development of film and glass negatives. But development is the stage in the operations wherein the greatest impatience pervades the mind of the amateur, who is naturally aglow to see the result his efforts. And, because that impatience may be quickly overcome by the employment of a rapid developing agent, he gratifies the desire to "see what it is like " by purchasing a "quick-action " developer, being entirely ignorant of the fact that, to use such developers successfully, the worker must possess a considerable amount of skill. I refer particularly to those agents with which a correctly exposed plate may be fully developed in two minutes or thereabouts, and by their rapid action completely turning the mind of the inexperienced worker into a chaos of misgivings as to whether the plate is over-exposed or only fully developed. It may appear to the reader that I would discourage the use of such developers; for the raw beginner, yes ; but not for the practised worker acquainted with their characteristics.
Let us suppose we are in the dark-room, standing by the side of a few-days-old amateur, and that he is using a metol developer. He slowly measures out the prescribed quantity of solution, finally adding a drop or two of bromide restrainer. Next, carefully, but seldom quickly, (although it is very necessary to cover the whole surface of the plate quickly when using this developer), he pours the solution over the plate. A few seconds pass, then the high lights appear; another few seconds go by, and the image is fully developed, but, because of the rapidity with which the detail has appeared, he cannot make up his mind whether the plate is over-exposed or merely fully developed. If such an occurrence takes place when treating a correctly exposed plate, how much more difficult his task will be when too much or too little exposure has been given.
But imagine him developing a negative with a slow developer. The coming of the high lights and the subsequent attainment of density are very gradual, allowing frequent examination, and the interval between the first appearance of the image and the final degree of density is such that it will give the untried worker reasonable time to consider whether the plate is fully developed, over or under-exposed, and to treat it accordingly. For the sake of precision, and to assist the amateur in elucidating these remarks, concerning the use of slow and quick-action developers, I will resort to the system of classification, although it cannot be expected that every agent will be fully dealt with.
These are the most universally used slow developers, though, especially in the case of the first named, the quantity may vary considerably, thus lessening or lengthening the time of development. As an ideal developer for the early worker and one that will allow him plenty of time, pyro cannot be beaten; and, although there are many who will probably disclaim its use for the beginner, in my opinion such repudiation is unnecessary. The very fact that the greater proportion of professional photographers still use pyro should be sufficient inducement to the amateur to do likewise. Its staining properties may be guarded against, whilst its suitability for all printing processes is a well-known fact. The correct proportion of pyro-soda and other developers are given below.
Hydrokinone is also very slow in its action, but has the peculiar property of adding density very quickly, once the image appears, and, unless the plate is continually examined, produces a hard negative in a very little while. It is so easy to over-develop with hydrokinone that beginners should be extremely cautious, and use it warily. Much the same advice may be given to those who would adopt eikonogen - ver-development being very frequent unless care is exercised. The addition of metol to hydrokinone, and the combination of hydrokinone with eikonogen, seems to have the effect of decreasing the chances of overdevelopment, at the same time increasing the rapidity of action.
These are probably the most rapid developing agents extant, and the first named is so energetic that a raw beginner will experience difficulty in exercising the necessary control. Amidol, although very popular in bromide work, is often retailed as a developer for negatives, but because it has a tendency to deteriorate when made up in solution, its use will never become so general as the first-named agent. Ortol is often recommended as a developer for films, and I have found it exceedingly useful for that purpose ; nevertheless, its energetic action will scarcely commend itself to other than practiced workers.
There are numerous other agents which, in the hands of seasoned amateurs, are capable of producing the finest results. I refer to adurol, rodi-nal, lycin, edinol, etc., but these may be classed as rapid-aetion developers. The combination known as pyro-potass-metol is, without doubt, a most successful developer for snap-shot work, and, when the embryo has mastered pyro-soda, he should use the former for developing his instantaneous exposures. Being a quick-action developer, he should not use it at the outset, lest its energy promotes confusion.
The chemicals contained in the following formulae are intended to be mixed : the ingredients of each formula with two ounces of water, which quantity is sufficient to develop one half-plate :
Pyrogallic acid 4 gr.
Sodium sulphite 16 gr. Sulphuric acid (not necessary if developer is for immediate use).
Sodium carbonate 22 gr.
Hydrokinone 6 gr.
Sodium sulphite 36 gr.
Potassium carb. 44 gr.
Potass, bromide. 1/2 gr.
Eikonogen 7 gr.
Sodium sulphite 42 gr.
Sodium carb. 74 gr.
Potass. bromide 1/4 gr.
Metol 4 gr.
Sodium sulphite 44 gr.
Sodium carb. crystals 26 gr.
Potass bromide. 2 gr.
Amidol 10 gr.
Sodium sulphite 100 gr.
Potass. bromide 1 gr.
Ortol 4 gr.
Sodium sulphite 32 gr.
Sodium carb. 32 gr.
Potass bromide 1 gr.
Pyrogallic acid 4 gr.
Potass. bromide 1/4 gr.
Ammonia liq. .880, .16 m.
Metol 2 gr.
Hydrokinone 2 gr.
Sodium sulphite 48 gr.
Sodium carb. 30 gr.
Potass. bromide 1/4 gr.
Pyro 1 gr.
Metol 2 gr.
Sodium sulphite 12 gr.
Potass. carb. 12 gr.
Pot. bromide 1/8 gr.
Eikonogen 6 gr.
Hydrokinone 1 gr.
Sodium sulphite 54 gr.
Potassium carbonate 28 gr.
In every case the preservative should, first of all, be dissolved ; then the agent, and, lastly, the potassium bromide or restraining agent.
The following notes concerning the characteristics of developers, such as tint of negative obtained, of developers' keeping qualities, etc., etc., are inseparable in this treatise, and the beginner will do well to instill into his mind the peculiar properties of each. It is common knowledge that the tint of the negative is an important factor in printing, and a yellow-tinted but under-exposed negative will often give a better print than an under-exposed plate of a grey-black tone.
The brown-yellow image obtained with this agent is suitable for any printing process now on the market, and it is because of such utilization that pyro has enslaved the affections of the professional photographer. Pyrogal-lic acid is generally used with sodium carbonate and sulphites or liq. ammonia. Exposure to air will turn pyro in solution, yellow, and in this state it will considerably deepen the tint of the negative. An excess of pyro will produce a yellow stain, at the same time accentuating contrasts' Too great a proportion of the alkali (sulphite' etc.) is productive of flat, weak negatives.
Hydrokinone produces a brown-black image, and unless the negative is examined very frequently, over-development (causing density and too much contrast) will mar the result. Like yro, ydrokinone, when made up in solution, will turn brown on exposure to air, but in this case the discoloration does not affect the energetic properties of the developer. The alkalies generally recommended for hydrokinone are caustic soda and potass. carbonites and sulphites. Regarding the former, too free a use of the caustic will soften the emulsion of the negative. and excessive forcing often produces a disagreeable yellow stain.
Grey-blue negatives are obtained with eikonogen ; the alkaline solution being generally composed of neutral sulphite and carbonates. In all other particulars it resembles hydro-kinone.
Metol produces a grey-black negative, and is used with alkaline carbonates. In solution metol keeps well. As a developer its use is very popular, both for plates and bromide papers.
Negatives of the grey-black tint are obtained with amidol. It is an ideal developer for bromide papers, but in solution its keeping qualities are not good. If the solution assumes a a reddish tint, it should be thrown away, for in this state its energies are practically exhausted.
Ortol possesses similar properties to metol, and is used in much the same manner.
I believe it has been pointed out before in these pages that exactitude is essential, but I should also like to add that unless the observance of this rule is rigidly self-enforced, defective negatives will often make their appearance. Should you use more of the principal agent than is recommended, you will find too much contrast in your negatives, and the light portions will be clogged. Again, if too little is used your negative will lack brilliancy and you will generally find development unnecessarily prolonged.
If you will add more than the prescribed quantity of alkali, you will certainly accelerate development, but your negatives will be flat and dense while fog and granulation may also make their appearance. Be sure that you are using only the recommended quantity of water; also that the temperature of the latter is approximately 70° Fahr. A warm developer produces fog ; a cold one, flatness. - Focus.
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