by John Sexton,
copyright © 1987.
Reproduced with permission for the Large Format Page
This article was orginally published in Darkroom Techniques, March/April issue 1987, Vol. 8, No.2. The current publication name is Photo Techniques. The information was accurate to the best of John Sexton's knowledge at the time it was published. It may or may not be applicable to today's methods. Thanks to Alan Shapiro for scanning.
The introduction of the Kodak T-MAX family of films has sparked an amazing amount of new interest in the medium of black and white photography. The films also have raised many questions for beginning as well as experienced photographers concerning the proper handling of this new generation of black and white films.
The T-MAX films differ from conventional black and white films in both camera use as well as processing. They offer superior grain to speed performance, along with greater flexibility of contrast control in processing. For the careful photographer the films can be valuable tools and are well suited to Zone System applications. Some suggestions that may help optimize their performance follow, based on the past three years of my personal experience working regularly with these films.
IN THE CAMERA
T-MAX films require no real difference in exposure technique for most applications. One important difference is that the T-MAX films (T-MAX 100 in particular) have greatly improved reciprocity characteristics compared with most other films. Kodak Publication F-32 gives some useful, and accurate, starting points for reciprocity compensation.
This means the films maintain their speed much more effectively with long exposures. I find this to be a great advantage in my own work where I often encounter exposures ranging into the minutes. T-MAX 100 actually becomes "faster" than Tri-X at about 1 to 2 minutes of exposure!
T-Max films have a different spectral sensitivity than most other panchromatic films. They "see" colors in a way that is closer to human eyesight. There may be some differences in filter factors with T-MAX films. Once again, check publication F-32 for filter factors that seem to be accurate starting points.
EXPOSURE AND DEVELOPMENT
I strongly recommend each photographer conduct some type of personal film speed and developing time test. As with most black and white negative films I used an Exposure Index (El) that is less than the manufacturers' suggested film speed. T-MAX 100 and 400 were both initially tested by the Kodak laboratories in D-76 developer, and performed exceptionally well in this developer. They also perform well, and will have slightly higher film speeds, in the T-MAX developers.
T-MAX 100 works satisfactorily in HC-110 developer, but the speed is not as high, and it is grainier than other developers. I do not personally care for T-MAX 400 in HC-110.
My developers of choice for sheet film use are D-76 and T-MAX RS Developer-Replenisher. At this point I prefer the following procedures for normal contrast. The times below should be good trial data for roll film agitated for 5 seconds every 30 seconds, and for sheet film with continuous agitation in a tray. (The stack of film should be shuffled through about once every 30 seconds). I use ALL developers one-shot.
T-100 EI-64 D-76 1:1 12 min @ 68F T-400 EI-250 D-76 1:1 12-1/2 min @ 68F
T-100 EI-80 T-MAX 1:9 11 min @ 75F T-400 EI-320 T-MAX 1:9 10-1/2 min @ 75F T-100 EI-80 T-MAX RS 1:9 13 min @ 75F T-100 EI-320 T-MAX RS 1:9 12 min @ 75F
This data is for a typical diffusion enlarger. For negatives to be printed by condenser enlarger reduce the above times by approximately 20%.
Some photographers have encountered dichroic fog (an ugly brown metallic stain) on sheet film processed in T-MAX developer. The new T-MAX RS developer-replenisher should eliminate this problem with sheet film. If you encounter dichroic fog, one method of removing it is to immerse the wet negative into normal strength Farmer's Reducer for about 30 seconds with continuous agitation. This will have no effect on the density of T-Max emulsions, but will completely eliminate the Dichroic Fog. Wash the film after reduction.
For extremely high contrast lighting situations I have had excellent results using T-MAX 100 at EI-50 and processing in T-MAX RS developer-replenisher diluted 1:15 for 13 minutes @ 75 F. Agitation is normal for the first minute, then agitate 10 seconds every two minutes for the remainder of development. This will accomplish approximately N-3 development with little loss of film speed. This is a significant amount of contrast reduction ... experiment first!
NOTE: If you use D-76 developer be sure to use FRESH D-76 (not some that has been sitting around in a half-full bottle for a month!) As D-76 ages a chemical compound, hydroquinone monosulfonate, is formed. This chemical compound will INCREASE the activity of the developer and the contrast of your negatives in a big way with T-MAX. When mixing a gallon of D-76 I suggest storing it in 4 one-quart glass bottles filled to the brim. In this way you can work out of one bottle while the others remain full to minimize oxidation. If in doubt about the age of chemical ... dispose of it. There appears to be no similar aging problem with the T-Max system of developers.
FIXING AND WASHING
Use an ammonium thiosulfate fixer (i.e. Kodak Rapid Fixer, Kodafix or Ektaflo Fixer). These fixers will work much more quickly than a conventional sodium thiosulfate formula (Kodak Fixer). The ammomum thiosulfate will allow you to fix T-MAX films properly in 5-6 minutes in fresh fix - conventional fixers will take OVER 10 minutes. If you have film that is "pink' upon drying re-fix in a rapid fix formula and re-wash. Do not overuse your fixer ... T-MAX films will exhaust fixer more rapidly than conventional films.
The use of a washing aid such as Hypo Clearing Agent will reduce wash time, and help eliminate any of the magenta sensitizing dye so you will get nice clear film base.
INTENSIFICATION AND REDUCTION
Kodak Chromium Intensifier has little effect on T-MAX emulsions. However, Kodak Rapid Selenium Toner can be used as a very effective proportional intensifier on T-MAX. Selenium toner has the advantage that there is NO increase in grain size, and actually enhances the permanence of the negative.
I have found that I am able to increase the contrast about one full paper grade (N +1 is Zone System terminology) on a properly exposed T-MAX negative with selenium intensification. I intensify in Rapid Selenium Toner diluted 1:2 (strong!) with working strength Hypo Clearing Agent for 10 minutes at 68 F. The film is then washed normally. I have had good success with intensification of portions of large negatives to increase the contrast locally. This process is permanent - experiment with test negatives first!
Kodak Farmers Reducer mixed according to manufacturers' suggestions is not an effective reducer for T-MAX emulsions. If you need to reduce T-MAX films try Kodak Farmer's Reducer R-4a which is included in most formularies.
CONSISTENCY IS IMPORTANT
For years serious photographers, particularly those using the Zone System, have wanted a film that was flexible in contrast control like the 'good old films'. The contrast of T-MAX films tends to be considerably easier to manipulate than conventional films. What some of those photographers who were begging for films that could be easily 'moved around' did not think about is that a film that moves easily when you want it to will also change contrast with ANY variation in development. (Time, temperature, agitation, amount of film developed, etc). T-MAX is much more sensitive to any variables in your process, planned or unplanned, than most other films.
DO NOT USE T-MAX IF YOU ARE NOT CONSISTENT IN YOUR PROCESSING PROCEDURES. You MUST have repeatable work habits and procedures. Be concerned about 1 degree changes in developing temperatures. Process the film as carefully as you would color films, and you will get totally repeatable results. T-MAX films will teach you to improve your processing technique for repeatable results.
I have had the opportunity to work extensively with the T-MAX films for the past three years. I was fortunate to be one of a few photographers to work with the films during their prototype development. I feel I am just now beginning to know these films 'intimately'.
T-MAX 100 film has been my primary film since its introduction. It has an almost non-existent grain structure and a superb palette of grays that works well in rendering a luminous quality of light appropriate for my work. I use T-MAX 400 when I need the extra film speed.
For further information on T-MAX materials contact Eastman Kodak for the following publications: F-32 on T-MAX films; and J-86 on the T-MAX Developer Systems.
If you take the time to get to know these new materials - which will take time and experimentation - they can be valuable tools for your photography. GOOD LUCK!
Copyright © 1987 John Sexton
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