XXXIV 



RECREATION. 



ADUROL, A NEW DEVELOPER. 



silas w. nourse, in the Professional Photog- 

 rapher. 



Adurol is a bromine substitution product 

 of hydroquinone, and is distinguished from 

 it by a series of valuable properties. In 

 its qualities as a developer it stands mid- 

 way between hydroquinone and the more 

 rapid developers, metol and paramido- 

 phenol, working with the rapidity of the 

 last 2, yet yielding negatives of fine print- 

 ing qualities without the harshness of hy- 

 droquinone negatives. 



Adurol developers, whether made up in 

 one or 2 solutions, keep unchanged for con- 

 siderable time, in tightly stoppered or glass 

 stoppered bottles, and can be varied to suit 

 the operator's needs for detail, density, over 

 or under exposures. 



Its use is not limited to dry plates, like 

 pyro, but it can be used for developing bro- 

 mide papers, also velox and dekko papers, 

 which have practically revolutionized the 

 printing of to-day. 



The formula recommendea for dry plates 

 or films is as follows, for a highly concen- 

 trated stock solution : 



200 cubic centimeters == J; ounces, distilled 

 water. 



150 grammes = 5 ounces, carbonate of pot- 

 ash. 



75 grammes = 2 l / 2 ounces, sulphite soda, 

 pure crystals. 



The mixture becomes warm of itself 

 from the solution of potash. To the some- 

 what cloudy solution, while still warm, add 

 15 grammes, y 2 ounce, adurol. 



Dissolve by shaking. Allow it to stand 

 a short time, and then filter, although it is 

 not absolutely necessary to filter. 



For use take J / 2 ounce stock solution, 5 

 ounces to 7)/ 2 ounces water. For over ex- 

 posures, add more water. For under ex- 

 posures, less water. For bromide paper, 

 take one part of stock solution to 30 or 40 

 parts of water. For velox or dekko paper, 

 one part to 5 parts of water. 



Formula No. 2, for 2 solution developer : 



A.— Dissolve in 500 grammes, 16 ounces, 

 water. 

 Dissolve in 50 grammes, 1 2-3 ounces, 



sodium sulphite, pure crystal. 

 And add 10 grammes, 1-3 ounce, adu- 

 rol. 

 B. — Dissolve in 500 grammes, 16 ounces, 

 water. 

 Dissolve in 60 grammes, 2 ounces, car- 

 bonate potash. ; 



For use on dry plates, films, velox or 

 dekko papers, take equal parts of A and 

 B. For more density, add a little more. 

 For bromide paper, dilute equal parts of A 

 and B with 3 to 4 parts of water. 



For velox and dekko papers the follow- 

 ing formula has been tried: 



10 ounces water. 



40 grains adurol. 



Yz ounce sulphite soda, pure crystal. 



400 grains carbonate of soda crystal. 



The foregoing works as well as the metol 

 and hydroquinone solution recommended 

 for these papers. In fact, each of the 3 

 formulae was tried with and without the 

 bromide of potassium solution, and the 

 whites remained as clear without the bro- 

 mide as with it. 



The test was made with prints from the 

 same negatives, one developed with metol 

 and hydroquinone, one with adurol with- 

 out bromide, one with adurol with bro- 

 mide, and the results were as fine with the 

 adurol as with the metol and hydroquinone ; 

 but it was found that less bromide was re- 

 quired with the former than with the lat- 

 ter to obtain olive tones, and in preparing 

 the developer it will be found less trouble 

 to weigh out one quantity than a little of 

 2 developers. 



Next in order was to save the 2 solu- 

 tions, the adurol and the metol hydroqui- 

 none, to see which discolored first, so each 

 was put in a glass stoppered bottle and al- 

 lowed to stand a week. The former is 

 quite clear, while the latter is badly dis- 

 colored; in fact, of a Van Dyke brown 

 tint, while the adurol is more of a lemon 

 tint. Hence for those who do not care- to 

 make up a fresh developer with each batch 

 of velox or dekko print, adurol will be 

 found the more convenient, it being the 

 better keeper; and when slightly weakened, 

 from developing prints, it will be found 

 adapted to the developing of plates and 

 films. 



If so, why not get a good one ? 

 And why not get it free of charge ? 

 This is easy. 



Any old box will answer the purpose if it 

 does not leak light; but you must have 

 a fine lens to make a fine picture. 



You can get 



A Royal Anastigmat 

 Lens, 4x5, Series No. 1 



Made by the Rochester Lens Co., Rochester 

 New York, 



And listed at $45, 



For 20 yearly subscript 



tions to RECREATION 



You can get any other lens made by this 

 Company on a basis of one subscription 

 to $2. of the list price of the lens. 



Sample copies of Recreation for use in 

 soliciting furnished on application. 



