964. Manipulation Of Iris Paper

Manipulation Of Iris Paper. "Iris" is of exceptionally fine printing quality and possesses all of the finer points of quality and tone necessary for the better grades of contact printing. This brand is especially recommended for portraiture, and in fact all work where quality, gradation and tone values are required. With its three surfaces all of the most desirable photographic effects may be obtained. Iris paper is made in three surfaces and two weights.

965. Regular Weight. For mounting. Smooth lustre surface. ( See 1909 REVISION ON PAGE 293.)

Extra Heavy. Does not require mounting or backing. Smooth surface without lustre.

Medium Rough. Heavy stock with light grain.

966. The speed of Iris paper permits handling it in ordinary yellow artificial light without the use of red or orange light screen.

967. Exposure

Exposure. The length of exposure of course depends on the density of the negative; also the strength of the light used for printing. After becoming familiar with the speed of the paper all that is necessary is to judge the density of different negatives. For the beginner, a test should be made by covering some important part of the negative with a small strip of paper and exposing it to the light. When exposure is thought to be sufficient, remove the test strip and develop it. If the exposure is correct, the image will develop to the desired depth and pause in development. If the image stops developing before the desired depth is reached, it will indicate under exposure. If the image develops beyond the desired depth before development stops, it will indicate over exposure.

968. "Iris" developer should be mixed according to the following formula. Other developers may be used (see general information), but we recommend the following as giving good color and gradation:

Water..........................................

40 ozs.

Metol..........................................

14 grs.

Sulphite of Soda (Dry).........................

.1/2 oz.

Hydroquinone...............................................

60 grs.

Carbonate of Soda (Dry)................................

.1/2 oz.

969. When ready to develop add one drop of a saturated solution of bromide of potash to each two ounces of developer. Chemicals should be dissolved in the order given, thoroughly dissolving each one before adding the next. If sodas in crystal form are used, double the amount given in the above formula.

970. The dry print should be immersed face up in the developer with a sliding motion. Break air-bells that may form by rubbing the surface with the tips of the fingers, or a tuft of cotton.

971. A properly exposed print will develop to the desired depth freely without forcing the development. The deeper shadows of the image appear first, and as development proceeds, the half-tones and highlights will build in. The image will appear shortly after the print is immersed in the developer. The development will proceed evenly and slowly enough to give full control during development. The speed of development depends largely on the temperature of the developer and the quality of chemicals used in the developer. The best temperature for developer is about 65 degrees Fahrenheit.

972. When a print is completely developed it will apparently stop or pause in development. If a print is under-exposed and over-developed, or forced, it will be cold or blue in tone, lacking richness in the shadows and detail in the highlights. Forced development is also apt to cause impure or fogged whites. If a print is over-exposed and under-developed, it will have reached the desired depth before development has paused or stopped. An under-developed print will be harsh, lacking detail in both highlight and shadow. Extreme over-exposure will result in a flat muddy print.

973. The developer formula, as previously given, will prove satisfactory for the ordinary run of negatives, but in extreme cases it can be modified to advantage. When negatives are inclined to be flat or weak, the amount of hydro-quinone should be doubled. This together with full exposure will increase the brilliancy of the print. By " full exposure," slightly over normal is meant. For contrasty negatives, use regular developer with double the regular amount of bromide, adding one drop of the following iodide solution to each ounce of developer.

Iodide Solution

Water..........................................

4 ozs.

Iodide of Potash Crystals............................

.1 oz.

974. More or less iodide will produce similar degrees of contrast. Care should be taken in the use of iodide, as when the quantity is beyond a certain point it will act to the extreme. Expose prints long enough to print through the highlights of the negative. Iodide will take care of the shadows in the print and prevent them from becoming too intense. The best tones on "Iris" are obtained by making decidedly olive tones and then toning as directed hereafter. To obtain the necessary olive in the prints they should be exposed so that they will develop to the proper depth without forcing. Bromide of potash is important in producing olive tones, and at least as much as is called for in the developer formula should be used. Local water conditions may make it necessary to use an increased amount of bromide to obtain the necessary olive. Using one drop of nitric acid to each ounce of developer will also assist in producing the olive tone.

975. After prints are developed rinse in acid shortstop.

ACID SHORT-STOP.

Water.....................................................

32 ozs.

Commercial Acetic Acid................................

..1 Oz.

976. The exact proportion of the short-stop is not important, but this bath should be kept acid at all times, because only as long as it remains acid will it act as a short-stop. Carrying developer into it with prints will in time neutralize it. It is easily mixed and should be kept fresh. After rinsing prints, transfer them immediately to the fixing bath and be sure to quickly and thoroughly immerse the prints in the solution.

977. Fix prints face up to prevent air-bells from forming on the surface of the print. Air-bells in fixing cause round dark spots, or streaks, to appear on the print.

FIXING BATH.

Water.........................................

64 ozs.

Hypo......................................

16 ozs.

Dissolve and add the following hardening solution:

Water..........................................

5 ozs.

Sulphite of Soda (Crystals).......................

1/2 oz.

Commercial Acetic Acid........................

3 ozs.

Powered Alum.......................................

1/2 oz.

978. It is important to mix fixing bath exactly as given. This bath will keep indefinitely and can be used repeatedly until exhausted. A 64-oz. bath will fix at least two gross of cabinet size paper. When fixing bath is exhausted a clouded sediment will appear, and the bath will be frothy when violently agitated. Prints must be fixed no less than 10 minutes nor more than 30 minutes. (See instructions for fixing prints, Chapter XXXVII (Artura Paper - General Information And Difficulties), General Information.) After prints are fixed, they may be rinsed in fresh water and should then be toned. The decided olive color is converted into a proportionate amount of brown in the toning bath. In this way, pleasing brown black tones are obtained. Unless prints are decidedly olive, the toning bath will have no apparent action. (See Development.)