The Moving Picture World (April 1907)

68 THE MOVING PICTURE WORLD. Hydroquinone ......"....... Soda sulphite.-.....-.-.-.-.•.-.-.•". To Our Readers. We are gratified with the encouragement given us by the profession, and the manner in which they have wel- comed The Moving Picture World. To all those we tender our thanks, especially to those who have sent us information of "what's doing," and who have assisted us with lists of names, etc. It is our aim to reach every individual interested in the field we cover, and to this end we ask our readers' help to complete our list of names so that it shall include every user of a cinematograph, stereopticon, song or story slide, and lecturer throughout the States. "The many can help the one, where* the one cannot help the many," is a saying that is world- wide, and if every one of our readers will sit down and write on a postal card, or a letter, or if these are too small, a sheet or sheets of foolscap, the names of those with whom they come in contact, giving a kindly word for the paper, we will reverse the above saying and show that one can help the many. Lantern Slide Developing. Simplicity in development and photography in general is all very well in a way, but the most exquisite slides I know of are to be secured by using rather complicated developers, or, in other words, "double" developers, and not combined, as Mr. Arnold Goldsmith advocates. (Pho- tographic News, June 30, 1905.) Don't hurry when making lantern slides; if you want to make haste be sure and do it very slowly. The best results, in my opinion, are obtained by slow development with weakened developers. Five minutes is none too much time to spend on developing a slide if the results warrant it Slow development gives a finer deposit of silver, and more pleasing tones. As stated above I use a double developer, and the formulae for my two favorites I give below. I would ask any reader who has not been successful with slides just to give them a trial. The two I swear by are amidol and hydroquinone, and the formulas are: Hot water 10 ozs. Soda sulphite 200 grs. Amidol 30 grs. This is double strength, and to use it add an equal part of water. One ounce of the above developer and one ounce of water make up two ounces of the finest "Part 1" developer. We must then have a "Part 2" developer, and this is made of hydroquinone, as follows: Potash carbonate,.. Water ... .120 grs. .... 480 grs. , i... 30 ozs. .. . . I Y2 ozs. ...-.10 ,-OZS. \ For use take of "A" i oz., "B" 3 drams, arid water to make 3 ozs*" . :- ' : ! " •< ■ y > ■*""• '\ The two developers being ready, take the exposed slide and place in the amidol solution until all the detail ;is visible and then transfer direct—without washing—to the hydroquinone developer, and rock until the proper density is obtained. The solutions may be used over and over again, and are therefore very economical. Development should be carried on a little.beyond what is desired in the finished slide, as .lantern slide images seem to "fix out" a good deal, especially in an acid fixing bath, and an acid fixing-clearing bath should always be used for slides. There are many formulae for such, but the following is the one I prefer: . No. 1. Hyposulphite of soda..' 8 ozs. Water ..... ,.*% pints No. 2. - Water % pint Add gradually sulphuric acid..-, x dr. Sulphite of sodium crystals..... 1 oz. Chrome alum ...»-. ,% oz. After the ingredients are dissolved, pour No. 2 solu- tion into No. 1. When the bath becomes weakened by constant use, it must be replaced by a new one. Prepare solutions Nos. 1 and 2 in advance (allowing plenty of time for the chemicals to dissolve) so as to have them ready when wanted. This bath remains clear after fre- quent use, does not discolor the slides, forms no precipitate upon them, and hardens the gelatine. The lantern plate should be allowed to remain in the bath five to ten minutes after the "whiteness" has disappeared from the plate. The permanency of the slide and freedom from stain, as well as the hardening of the film, depends upon this. Plenty of yellow light should be used when developing so as to be able to judge the density easily. Ruby light is not necessary, as lantern plates are not so sensitive as ordinary plates, and will not fog even with a large quan- tity of yellow light It is important to bear in mind that bad negatives will not give good clear bright slides, with the best plate and developer under the sun, although with care passable slides may be secured from negatives which are not quite perfect. Slides may be intensified or reduced the same as ~ ordinary negative, or toned as one does bromide * It is really wonderful how one may "ringr the c upon them. * ,,„„„..