Remember, the clearing time is the amount of time necessary for the complete removal of the milky appearance of the film (After one minute in Fixer 1, tanks can be opened and lights turned on so clearing time can be observed without risking damage to the film.). To fix film, first note the clearing time in fresh fixer for the film you are using. Instead of preparing only one fixing bath for each black and white process, prepare two identical baths. Stick to the processing times recommended by Kodak, and preferably to their chemistry as well. Do not follow these recommendations as they will lead to inadequate fixation. Also be aware that small manufacturers wish their products to appear to be better than Kodaks and other major brands, and therefore sometimes claim higher capacities for their products. It is therefore advisable to strictly follow the film or paper manufacturers recommendations for the number of films or prints to be processed in any given quantity of fixer (bleach/fix), replacing the fixer often. This leads to a sometimes significant risk of impermanence due to the inadequate fixation which may occur when a fixing bath nears exhaustion. In order to avoid such an undesirable result, it is necessary to forego the two-bath fixing scheme with color materials and instead employ the fixation technique recommended by the manufacturer. Before proceeding however, we should briefly discuss the fixation of color materials.īecause of the delicate balance built into color films and papers, using a two-bath fixing technique with these materials may produce unpredictable and unwanted shifts in color. This technique is to be used with all types of black and white film and paper and is very simple to follow. The only known way to assure that adequate quantities of fixer will be available for complete fixation is to use a two-bath fixing technique. In order for the unused silver and the thiosulphate compounds formed with it to progress through all of the necessary steps for complete fixation, adequate quantities of fresh fixer must be present to react chemically with the partially used fixer (silver thiosulphate compounds) present in the emulsion. Fixer that is far too stale to adequately complete all the steps of fixation is still more than strong enough to begin a process it cannot finish by clearing the emulsion (i.e., removing the milky appearance) and thereby make the film or paper appear to have been correctly fixed when it has not. The secret to correct fixation of any photographic material is in knowing that a large supply of very fresh fixer is necessary to effectively carry out the fixation process. The fixation process must therefore be absolutely complete, before one can wash the film or print successfully. The interim compounds formed before the fixation process is complete cannot be washed from photographic materials regardless of how long they are washed or how much water is used. The unused silver salts contained in the emulsion and the sodium thiosulphate (fixer) (rapid fixers are composed of ammonium thiosulphate) must go through dozens of chemical changes together before forming compounds capable of being washed from the emulsion or paper fibers. The removal of undeveloped silver halide from a photographic emulsion by fixation is a complicated process. The reason for this is that it is not possible to effectively wash photographic materials of any kind unless they have first been properly fixed. No discussion of the correct washing of photographic materials can be adequate without first mentioning correct fixation. So much has been learned in the past several years about washing and how it relates to the longevity of photographs that it has become necessary for us to change our approach to the washing of photographic materials almost completely. Photographic permanence is a subject that requires several articles for adequate treatment, but the correct washing of photographic materials is by far one of the most important aspects of photographic permanence and is therefore the subject of this article. From the beginnings of photography when Fox-Talbot was marginally successful at fixing the photographic image with table salt, to the present when plastic papers tend to yellow and crack, color dyes quickly fade, and a wide variety of outside forces work to destroy what we have labored so hard to produce, photographers have continuously fought to find ways to make their images more permanent. The greatest technical difficulty that faces and has always faced photographers is that of permanence. If you have a friend with whom you wish to share this information, your friend must visit this web site to get the article. No other reproduction, distribution or other use of any kind is authorized. (You may print 1 (ONE) copy of this article for your personal use. Fixing, Washing & Toning Fine B&W Photographs
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