Tuesday, June 3, 2008

EX CATHEDRA: Stamps and Box Nos, Iodine-Cyanide, "Close Up" Pictures, Print Washing.

Stamps and Box Nos.

           What is alleged by a correspondent to be a grievance amongst assistants who apply for situations advertised over a box number is the non- reply to such applications when a stamped and addressed envelope is enclosed for the purpose. It has been suggested more than once that the publishers of the “B.J.” should devise some plan by which the grievance should be removed. Out of curiosity we should like to know of a plan which would achieve this end, for we can conceive of none but that which applicants have in their own hands, viz., to refrain from sending stamps for this purpose. In this matter it is necessary for an applicant to put himself in the position of an advertiser who receives a score or more replies to an announcement. Naturally the applications from those who seem suitable are replied to, but the general commercial practice is to leave the others unanswered. That being so, the enclosure of a stamped and addressed envelope imposes on the advertiser an obligation which he has not invited, and which, therefore, he may disregard. No doubt there are some employers who will reply to every application from motives of old-fashioned courtesy or from a wish to obtain a reputation for consideration, but the majority will never think of it. And the assistant may be asked to think that the enclosure of payment for reply will not in any degree improve the chances of his engagement. It is inconceivable that any business man will be influenced in his choice of an assistant by the fact that he is saved the cost of three-halfpence in communicating with him. On the other hand, he may very easily interpret the fact as evidence of nervousness or want of confidence on the part of the applicant.

Iodine-Cyanide.

           For some reason or other the compounding of this reducer of prints and negatives is the cause of more queries to us than is any similar preparation. The failures of which our correspondents complain may be roughly divided into two classes: (1) Making the iodine solution, and (2) ensuring activity of the mixture. Failure under No. 1 can be infallibly avoided by working in a certain way; that of No. 2 arises from the varying strengths of commercial cyanide, and calls for adjustment by trial of the proportions of the two solutions. As regards the iodine, the secret of causing it to dissolve completely and quickly in the iodide is to add only just enough water to dissolve the crystals of the latter scarcely more than required to cover them, for they are very soluble and then to stir in the iodine flakes. These will dissolve almost instantaneously, and will remain in solution on diluting with water to the required volume. But if this latter is used for dissolving the iodide, the iodine is soluble in it only by the exercise of an enormous amount of shaking or stirring, and usually cannot all be got to dissolve. In regard to the second point, inactivity in reducing power of mixture of iodine and cyanide solutions is very often due to insufficient cyanide. The latter may be largely contaminated with cyanate which is inert in forming the reducer. Therefore, if the solution does not act as it
should further cyanide solution should be added; and if that fails, the solid cyanide is probably of too impure a quality and a brand of guaranteed 80 or 90 per cent should be bought. The reducer, of course, is not active unless containing a proper amount of iodine, which is used up in tin- treatment of prints, but, given that due proportion, want of energy in bleaching the silver deposit is occasioned by insufficient real cyanide.

"Close Up" Pictures.

           A little point which we have noted in several excellent cinematograph films is the very flat lighting in the large pictures of the leading actors and actresses. As most of our readers are aware, these are interpolated between the scenes in order to show more clearly the emotions which the character is supposed to be displaying. The effect is somewhat marred when the face is a ghastly white and the make up of the eyes and lips the only visible things. That this is unavoidable cannot be urged, for we have seen some such productions which would vie with finished portrait work, and it would seem that the defect is only due to a neglect to arrange for the special lighting which is necessary for a single face. On looking at good examples of this work we have wished that it were possible to make portraits of private sitters in the same way. There would be, we are sure, a good market for them if they could be produced at a reasonable rate, and a satisfactory method of showing them devised. The ordinary projection apparatus is bulky and inconvenient, and cannot be readily used in daylight. Probably many of our readers remember the original Edison apparatus in which the films were inspected by means of an apparatus somewhat resembling a magazine stereoscope, the illumination being by means of an ordinary incandescent electric bulb. In this apparatus the film was in the form of an endless band, so that the episode could be repeated as often as possible without rewinding. Some time ago we saw a cylindrical film on which the pictures were arranged in a spiral somewhat like a phonograph cylinder. If this idea could be carried out in a satisfactory way it should become popular. There have been attempts to make home cinematographs working with glass plate, but these are too fragile and cumbersome to appeal to the non-technical public.

Print Washing.

           As a rule it is some little time before the presence of hypo in an imperfectly washed print becomes manifest, but sooner or later it makes trouble for the careless producer. With ordinary black bromide or P.O. P. it may be months, even years, before a general yellowing of the image or uneven patches begin to appear, but with sepia-toned bromides retribution is swift, for deterioration sets in before the work is finished, and sometimes the cause is not suspected, the paper, the bleaching solution, and even the sulphide bath being blamed, while the fault is due to improper washing. The great fact to be remembered is that Farmer's reducer is composed of ferricyanide and hypo, and that no matter in what form or for what purpose a solution containing these two chemicals is applied to a print the effect will be the same. We all know that when a print has been locally reduced the tone of the reduced part will be different from that of the remainder; sometimes only slightly and at others very noticeably. Now a very small trace of hypo in a print is sufficient to react with the ferricyanide in the bleacher, and to start reduction of the image sometimes evenly and sometimes in patches or streaks. We have seen a batch of excellent prints which should have given excellent tones turn out a wretched ginger colour from this cause alone, and not only have the badly washed prints been affected, but properly washed ones have also been spoiled by the hypo conveyed into the bleacher by the former. Unless carefully watched many printers will trust to throwing prints into a large dish or sink and allowing a tap to run upon them, and if that tap runs for an hour they will say that the prints Lave been washed for that length of time. Failing a perfect mechanical washer there is no safe method of freeing prints from hypo except by hand washing, that is transferring the prints singly from one dish of water to another. Even as few as six changes of five minutes each in this way, provided that an ample quantity of water is used, will render prints safe for toning, and secure black ones from fading. There are two well-known tests for the presence of hypo, permanganate of potash and iodide of starch, and it would be well for anyone who is getting bad colours from apparently good black prints to apply one or the other. We know of one great firm which tests every batch of prints, bromide or gaslight, with permanganate, and the results are conspicuous for their good tone.

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