Developer 15,formula

Animal nutritionists have developed formulas to guide them in recommending the amount of food to feed animals in captive situations such as in zoos. First, the number of calorics needed to maintain the animal while at rest is determined—this is called the basal metabolic rate (BMR). In general, a reptile s BMR is only 15 percent that of a placental mammal, while a bird s is quite a bit higher than both a reptile s and a mammal s. For all animals, the number of calories they should receive on a maintenance diet is twice that used at the basal metabolic rate. A growing animal should receive three times the number of calories at the BMR, while an animal in the reproductive phase should receive four to six times the BMR. 

Finally, there have been numerous attempts to develop formulas that could be used to predict creep information under varying usage conditions. In practically all cases the suggestions have been made that the calculated data be verified by actual test performance. Furthermore, numerous factors have been introduced to apply such data to reliable predictions of product behavior. 

Lespieau s view was that organic chemistry must make use of physical methods and of physical chemistry and that the experimental work of Graham, Williamson, Wurtz, and, more recently, Raoult had confirmed the superiority of the atomic hypothesis over chemical equivalents. As for the meaning of the constitutional (structural, developed) formula,... 

A. Joly and R. Lespieau, Nouveau precis de chimie (notation atomique), Redige conformement aux programmes officiels du 31 mai 1902, 4th ed., 3 vols. (Paris Hachette, 190405), quotations, III 419, 437. The "brute" formula is of the type C2H60 the developed formula... 

Renee Mestrallet Guerre also designates the "semi-developed formula" C2H50H in "Communication, Linguistique et Semiologie."... 

Fig. 3.73. Developed formulae of indigo and indigo carmine. Reprinted with permission from M. Vautier et al. [141].

The most widely used developer in the world, Kodak D-76, fells under the category of general-purpose developers. D-76 was formulated in 1927 byj. G. Capstaff of Kodak as a black and white movie film developer. However, not long afterwards better movie-film developing formulas were introduced and D-76 found use as a still-film developer. Eventually, it became the standard by which to judge all other developers. It was not that D-76 was the best developer ever formulated. It was more that a standard was needed and D-76 had the best all-around compromise of sharpness to grain with a full tonal range from black to white. 

Pyrocat-HD is a Pyrocatechin/Phenidone-based developer formula that can be used for development in tanks or trays. It is also recommended for JOBO and other rotary type processing in tubes and drums. Although originally meant for sheet film, subsequent use has shown that it is also an excellent developer for use with 35 mm and medium-format films because of its high acutance and tight grain pattern. 

To increase the flexibility of MQ and PQ print-developing formulas, keep a bottle of carbonate solution and a bottle of 10% bromide on your darkroom shelf. I learned this trick from photographer Edna Bullock, who learned it from her husband, Wynn Bullock. Wynn used this technique with Ethol LPD paper developer. 

All three of the famous Westons—Edward, Brett, and Cole—used amidol paper-developing formulae. All three were famous for their rich blacks and full-scale print tones. All three used different amidol formulae. There is some confusion as to the formula each one used, and more than one has surfaced for Brett and Edward. It may be possible that they used different formulae during the course of their long careers. 

Most authors recommend the first developer be very active and include a silver solvent, such as potassium thiocyanate or sodium thiosulfate, in order to clear the highlights in preparation for redevelopment. D-19 + 30 ml of sodium thiocyanate = D-67 which fits the description as does D-76 + Thiosulfate. However, going against tradition David Wood recommends not using anything with thiocyanate or thiosulfate in the first developer. Instead, he recommends the use of Kodak D-l 1. All three first developer formulas are given in Formulas Reversal Processing. 

Uses As a solvent of most resinous substances. Used in some developer formulas as a source of alkali by reaction with sulfite useful as a drier and as an ingredient in toning formulas. Caution Highly volatile and inflammable. 

Uses In developing formulas for its high solvent properties. To replace alcohol wherever it is called for. To control the diffusion of solutions into emulsions. 

Notes Glycin is almost insoluble in water, but it dissolves readily in alkaline solutions, thus it should be added last to any developer formula. It oxidizes very slowly and is very clean working. 

EXAMPLE Suppose a developing formula recommends using between 10 and 14 minutes.With an ISO 125 film, start by developing a test roll for 12 minutes. With an ISO 50 film, develop for 25% less, or 9 minutes.With an ISO 400 film, increase by 25% to 15 minutes. This is a rough rule, and you may find that it is too much or too little. That is why an initial test roll or two is recommended. 

Developer formulas are not carved in stone. They can be adjusted to customize the results by making one or more of the following changes. 

This is one of the best divided developer formulas for fine grain and full tonal scale. For the first bath you can use classic D-23 or a modified version, given here. This is because when... 

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