Last winter, I shot six or seven rolls of film — color and black and white. I was pleased with the results—the B&W showed a pleasing, but not overwhelming, amount of grain, even at 400 ISO. The color was the same. Then, in March and April, I began testing LTM lenses and a few new cameras using Kentmere 400, HP5+, and Tri-X, and the results were quite bad—artifacts, grain, stains, streaks, reticulation—everything seemed to go wrong. I wrote about my troubles with reticulation with Tri-X and HP5+ in a previous post. That post was written before I discovered my thermometer was off by 18F.
It turns out that the temp of my PhotoFlo solution was causing the reticulation of the HP5+ and Tri-x, but not in the way I thought. The PhotoFlo solution was at room temperature, but I had been developing the film in 88F DF96 and washing with equally warm water! Since DF96 accomplishes pushing by increasing the temp, I was unintentionally pushing all of my B&W film two stops or more. Fortunately, only two of the ten or so rolls were intended for display. The rest were test shots. One roll of Arista 200 (120) and one roll of Kentmere 400 (35mm), intended for posts, had excess grain, streaks, loss of shadow detail, and other defects. Compare this 6×4.5 Arista 200 image (left) and its level of grain and artifacts to that of a 6×4.5 Kentmere 400 image developed in February before the thermometer issues.
Fuji 400 and Phoenix 200 met the same fate. Both were developed using CineStill’s color kit and washed at about 120F. The Harman Phoenix 200 seemed to be no worse off due to the higher dev temps. On the other hand, the Fuji 400 did not fare as well. Out of 36 frames, perhaps 10 or so are usable, but the defects secondary to the high dev temps — color shifts, excess grain — are apparent.
Needless to say, I am now paranoid when it comes to thermometers. I keep three on hand. There is approximately a 0.3-degree variance in readings among the them. Before developing, I select one, ensuring it aligns with the other two. Maybe this is overkill, but I learned this lesson the hard way. The thermometer I had been using since 2020 failed without warning, and I didn’t notice it. Multiple thermometers appear to be the best solution for now. Don’t let a bad thermometer ruin your precious negatives—keep at least two on hand and check them frequently.
