When we compare the present prices of nearly all chemicals with those ruling before the war we find that the increase in the year's expenditure in this direction is a serious matter, and as it is a matter of percentages as serious for the small user as for the large one, whether the expenditure be five pounds or five hundred, it is important that full value be obtained for it, and this can only be done by keeping a watchful eye upon every stage of the work.
Very often waste begins even before solutions are made up. This is usually due to the want of proper receptacles for the stock when it is delivered. Quite often chemicals, such as sulphite and carbonate of soda, alum, and even ferricyanide are purchased in paper packages of twenty-eight pounds or less, and taken into use at once without putting into proper jars, the parcels being laid upon any convenient shelf exposed to the air and dust, besides often being scattered upon the shelf or floor. It certainly should not be necessary to allude to such a state of things, but it undoubtedly exists in many places, and should be stopped without delay. Next to this is the practice of guessing at quantities when mixing solutions, for in this way a loss of 10 to 20 per cent, may easily occur, especially in the heavier kinds we have mentioned. It is not necessary to weigh most chemicals carefully as a system of dry measurement is usually sufficiently accurate, but it is desirable to keep in each jar or cask a measure which will hold what may be called the unit quantity, so that any boy or girl may be entrusted to make up the usual bulk of solution without supervision. Nearly everybody makes up certain quantities of solution at a time. To take the case, say, of pyro developer, the jars holding sulphite, carbonate, and metabisulphite should each contain a vessel such as a jam-pot or one of the cardboard canisters now commonly used, which when filled to the brim and struck off level will hold exactly the quantity required for a Winchester of solution. The card canisters are convenient, as they may be cut down to the right depth with a penknife. The pyro itself is usually supplied in ounce bottles, so that no measurement is needed, but if purchased in bulk in the crystal form it should also be measured, or, if in the old resublimed state, carefully weighed. This should be done not only as a means to economy but al-o as tending to uniformity of result. The same system should be applied to other solutions, such as amidol, hydroquinone, and such things as reducers and intensifies, the only exception being when the stock solutions are saturated ones. With amidol developer the practice of making a stock solution of sulphite and adding the dry amidol as needed is an especially wasteful one, as there is always the possibility of using more than is needed, and. moreover, neither the mixed developer nor the sulphite solution keep in working order so long. The better way is to make a fair quantity of solution at once with the addition of meta-bisulphite as a preservative. A good formula is two ounces of sulphite of soda and a drachm of metabisulphite dissolved in twenty ounces of water to which is added a quarter of an ounce of amidol. This is diluted with an equal bulk of water for use, and will keep in good order for a week or more. It is frequently the practice to throw away amidol solution which has been little used, and although we do not advocate overworking it, it has been found quite practicable to keep used developer over from day to day, adding fresh a- needed. In one studio the amidol was kept in a jug after use, and only thrown away when the excess of bromide rendered it necessary. The prints produced by this procedure were as good as most that we have seen. In this case we may say that no bromide was used in making the original solution.
A very common cause of waste is to be found in a hurried, sloppy method of working, by which much solution is carried away upon the prints, e.g., when removing enlargements from the fixing bath. If a print is lifted quickly out of the hypo quite an appreciable quantity is carried into the first washing water, and at the and of the day's work the bulk is seriously reduced. With hypo at six shillings a hundredweight this is a small matter; at sixty shillings it is not. Even more wasteful is this practice in sulphide toning. Some printers’ wasteful quite half of the costly bleacher in this way.
Those who still work the gelatino-chloride or P.O.P. printing will find that the Eastman system of allowing a definite quantity of gold to a certain number of prints a very economical way of working, practically all the gold being used. For the benefit of those unacquainted with the plan we may explain that if a grain of gold be allotted to each dozen cabinets for a purple tone, by diluting the solution a larger number may be toned to brown or still more to a reddish colour, all the prints being put in at once and allowed to remain, until the bath is exhausted. This not only saves gold, but ensures even toning.
Using an excess of solution for any purpose is so obviously wasteful that it hardly needs mentioning, yet it is frequently done. We have often seen three times the necessary quantity of ferricyanide reducer made up for cleaning a few bromide prints, while pyro developer is often used in a too lavish manner, especially when concentrated stock solutions are used. It is false economy to stint the developer, and many poor negatives are the result, but many assistants habitually use twice as much or even more than is really necessary.
Although not strictly within our subject, the waste of bromide paper through careless cutting or tearing deserves a word. One often sees prints with a margin nearly half the area of the finished print. This is not only wasteful of paper, but of all the solutions used. Odd-shaped enlargements such as eleven by seven upon twelve by ten paper run away with a strip which if trimmed off before exposure would serve for tests or even for small prints. All these little things mount up in a year, and even if the exact amount saved cannot be calculated the profits will appear appreciably better. Wartime orders are at an end now, and it is well to bear in mind the old proverb that a penny saved is a penny earned. There is another which says penny wise and pound foolish. The wise man will steer between these extremes.
Very often waste begins even before solutions are made up. This is usually due to the want of proper receptacles for the stock when it is delivered. Quite often chemicals, such as sulphite and carbonate of soda, alum, and even ferricyanide are purchased in paper packages of twenty-eight pounds or less, and taken into use at once without putting into proper jars, the parcels being laid upon any convenient shelf exposed to the air and dust, besides often being scattered upon the shelf or floor. It certainly should not be necessary to allude to such a state of things, but it undoubtedly exists in many places, and should be stopped without delay. Next to this is the practice of guessing at quantities when mixing solutions, for in this way a loss of 10 to 20 per cent, may easily occur, especially in the heavier kinds we have mentioned. It is not necessary to weigh most chemicals carefully as a system of dry measurement is usually sufficiently accurate, but it is desirable to keep in each jar or cask a measure which will hold what may be called the unit quantity, so that any boy or girl may be entrusted to make up the usual bulk of solution without supervision. Nearly everybody makes up certain quantities of solution at a time. To take the case, say, of pyro developer, the jars holding sulphite, carbonate, and metabisulphite should each contain a vessel such as a jam-pot or one of the cardboard canisters now commonly used, which when filled to the brim and struck off level will hold exactly the quantity required for a Winchester of solution. The card canisters are convenient, as they may be cut down to the right depth with a penknife. The pyro itself is usually supplied in ounce bottles, so that no measurement is needed, but if purchased in bulk in the crystal form it should also be measured, or, if in the old resublimed state, carefully weighed. This should be done not only as a means to economy but al-o as tending to uniformity of result. The same system should be applied to other solutions, such as amidol, hydroquinone, and such things as reducers and intensifies, the only exception being when the stock solutions are saturated ones. With amidol developer the practice of making a stock solution of sulphite and adding the dry amidol as needed is an especially wasteful one, as there is always the possibility of using more than is needed, and. moreover, neither the mixed developer nor the sulphite solution keep in working order so long. The better way is to make a fair quantity of solution at once with the addition of meta-bisulphite as a preservative. A good formula is two ounces of sulphite of soda and a drachm of metabisulphite dissolved in twenty ounces of water to which is added a quarter of an ounce of amidol. This is diluted with an equal bulk of water for use, and will keep in good order for a week or more. It is frequently the practice to throw away amidol solution which has been little used, and although we do not advocate overworking it, it has been found quite practicable to keep used developer over from day to day, adding fresh a- needed. In one studio the amidol was kept in a jug after use, and only thrown away when the excess of bromide rendered it necessary. The prints produced by this procedure were as good as most that we have seen. In this case we may say that no bromide was used in making the original solution.
A very common cause of waste is to be found in a hurried, sloppy method of working, by which much solution is carried away upon the prints, e.g., when removing enlargements from the fixing bath. If a print is lifted quickly out of the hypo quite an appreciable quantity is carried into the first washing water, and at the and of the day's work the bulk is seriously reduced. With hypo at six shillings a hundredweight this is a small matter; at sixty shillings it is not. Even more wasteful is this practice in sulphide toning. Some printers’ wasteful quite half of the costly bleacher in this way.
Those who still work the gelatino-chloride or P.O.P. printing will find that the Eastman system of allowing a definite quantity of gold to a certain number of prints a very economical way of working, practically all the gold being used. For the benefit of those unacquainted with the plan we may explain that if a grain of gold be allotted to each dozen cabinets for a purple tone, by diluting the solution a larger number may be toned to brown or still more to a reddish colour, all the prints being put in at once and allowed to remain, until the bath is exhausted. This not only saves gold, but ensures even toning.
Using an excess of solution for any purpose is so obviously wasteful that it hardly needs mentioning, yet it is frequently done. We have often seen three times the necessary quantity of ferricyanide reducer made up for cleaning a few bromide prints, while pyro developer is often used in a too lavish manner, especially when concentrated stock solutions are used. It is false economy to stint the developer, and many poor negatives are the result, but many assistants habitually use twice as much or even more than is really necessary.
Although not strictly within our subject, the waste of bromide paper through careless cutting or tearing deserves a word. One often sees prints with a margin nearly half the area of the finished print. This is not only wasteful of paper, but of all the solutions used. Odd-shaped enlargements such as eleven by seven upon twelve by ten paper run away with a strip which if trimmed off before exposure would serve for tests or even for small prints. All these little things mount up in a year, and even if the exact amount saved cannot be calculated the profits will appear appreciably better. Wartime orders are at an end now, and it is well to bear in mind the old proverb that a penny saved is a penny earned. There is another which says penny wise and pound foolish. The wise man will steer between these extremes.
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