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Tech Notes
Earlier this year Kodak announced that, during the course of the year, most members of their A-Team of black-and-white films would be undergoing significant change. Plus-X, Tri-X, T-MAX 100 and P3200 would be moving to a different manufacturing facility. This was widely viewed as a good news-bad news story. The films were moving to Kodak Rochester’s newest production facility, and this held the promise of improved product consistency, better physical properties, and, most important, it went a long way to insuring the continued availability of these products in the future. We are speculating that if production volumes of traditional silver films were to decline sufficiently, Kodak might classify some of their older coating facilities as excess manufacturing capacity and close them. Products produced exclusively in such older facilities would be at real risk of discontinuance. Having the B/W films routinely manufactured in their newest and best facility greatly diminishes the chance they would be dropped if this scenario played out. At the same time, the change carried potential for a major downside. Kodak predicted photographers would see little change in the performance of these products except for some minor adjustments to development times.
Kodak has subsequently published on their web site new processing recommendations for these films, and some of the changes these reflect are far from “minor”, recommended new times for some film-developer combinations differing by as much as 50% from what they were! Our lab (www.4photolab.com) has been processing B/W film for customers worldwide for over 20 years and our procedures are finely honed. The thought that all of these procedures might be out the window was a matter of no small concern! Accordingly, we partnered with a local company, Dick & Silvia’s B/W Toolbox, Inc., to do some serious testing. Dick Dickerson and Silvia Zawadzki, proprietors of the Toolbox, are Kodak retirees who were responsible for the original design and testing of many of Kodak’s B/W products. They acquired brick quantities of all the “old” and “new” films in 35mm format and exposed them. We ran many process variations and made our darkroom facilities available to them to prepare carefully matched comparison prints. The 35mm format was selected as it requires greater magnification in printing and this makes it easier to see changes in such parameters as sharpness and graininess. Historically Kodak has, with few exceptions, coated the same basic emulsion system on different supports to produce different film formats, so we expect our findings for 35mm are applicable to 120/220 and sheet products as well.
Their film exposures were of two types: Sensitometric (step tablet) exposures allowed construction of D-Log E curves for precise selection of optimum development times as well as identifying any changes in curve shape (tone reproduction) and any shifts in real film speed. “Test Target” photographs ultimately yielded prints incorporating bar charts, grain sweeps, color checkers, tests of highlight and shadow detail and a copy print of a full range scene to assess tone reproduction. For our part, we assessed both manual (small tank) and rotary tube processing using three of our standard developers: D-76 (1:1), Xtol (1:1) and T-MAX (1:4).
Surprise! In every case the development time we ultimately selected was identical to what we had been using previously! We prepared, in all three developers, head-to-head comparisons, new vs. old, of all of the films – Plus-X, Tri-X, T-MAX 100, 400 and P3200 (never mind Kodak said T-MAX 400 was unchanged as it had always been produced in the new facility). And we found no need to change any of our tried and true development times. The D-Log E curves all virtually overlapped and printing the test targets to matched densities required paper grade adjustments of no more than half a grade.
Kodak’s charts of extensively modified process times remain a mystery. Granted we have explored only a few of the hundreds of developer-device combinations available to photographers, but our recommendation to those of you who do your own souping is this: When you are ready to process any of the “new” films, first try using the same times you always have. If the results prove, on printing, to be too flat or too harsh it would be appropriate to lengthen or shorten that development time accordingly. A time change of 10% would likely move a film on the order of a half to a full paper grade in terms of how it prints; a 25% change might be one to two grades. However, we are inclined to think there is a very good chance you will be completely satisfied developing the new films exactly as you did the old ones.
We were pleased to see how many other features of the new films indeed remain unchanged. Real film speeds are no different – continue to expose the films as you always have. The detailed shapes of D-Log E curves are no different – expect the same tonal properties you have been accustomed to. Sharpness appears no different. Gray rendering of colors is unchanged. But there are some other changes you should be aware of!
The test target contains a gray sweep that covers the range of densities where people are most sensitive to graininess in a B/W photograph. The target’s dimensions and camera-to-target distance is such that this sweep is enlarged 16X linear in printing. Even small differences in product graininess are readily evident in the resulting prints, and differences were certainly evident here in all but one case.
That one case was Plus-X film: We see no difference in graininess between the old and new versions of this product. In the case of T-MAX 100, we see a small difference, the newer product being slightly coarser grained. This difference would probably pass unnoticed in a smaller enlargement, as with a full frame 8x10 print from 35mm or if printing from a larger format version of the film. T-MAX P3200 is now appreciably coarser grained than it was, reminiscent of products of days gone by such as Royal-X Pan or Recording Film - except that P3200’s grain is sharp and lacks the oatmealy appearance of those former films. The “new” Tri-X has changed in the other direction – it is now very distinctly finer grained than it was. In fact it is not terribly far removed from the grain position of the much slower Plus-X film. And T-MAX 400? This is the one Kodak reports to be unchanged, having been manufactured in the new facility all along. Nevertheless, we find our most recently purchased samples to be appreciably coarser grained than the older stock we acquired for direct comparison. In fact, if our sole criterion were achieving the finest possible grain, we would hands-down choose Tri-X over T-MAX 400. Of course our samples of new T-MAX 400 were all from a single production run. Perhaps that one run was a sport? That is always possible, but in our experience, graininess is a characteristic of a particular product and shows very little batch-to-batch variability.
All things considered, the tests were a pleasant surprise. The new films do not require altered development times with the developers we routinely use – there is no need to segregate old and new films for processing. There are some important shifts in film graininess, but, understanding the differences, this is more of an opportunity than a problem. Otherwise we see nothing as different. And we can most fervently hope the reassignment of these products to Kodak’s newest manufacturing facility means they will continue to be available to us for many years to come!
Many thanks to Dick Dickerson and Silvia Zawadzki, of B/W Toolbox, Inc., for this article.
You can read more about our photo processes on this page. And be sure to check out our custom photo lab’s website: www.4photolab.com.
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Photographic Documentation of America’s Vanishing Roadside Culture
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