
Double-X at 1600 in Diafine 4+4, constant agitation using stick agitator. Leica M4 and 35mm Summicron IV.
As part of the batch of exotic film I ordered from Spain a couple of weeks ago, I bought some Double-X, a motion picture film stock which has many enthusiastic users. Usually I will shoot a new film at its box speed and find out what developer is most recommended and tweak from there. But not this time.

Double-X at 1600 in Diafine 4+4, constant agitation using stick agitator. Leica M4 and 35mm Summicron IV.
I sometimes read (and, rarely, participate in) Rangefinder Forum, which had a particularly long thread about the film. That thread has morphed into an excellent resource, Project Double-X. On that site I found a published time for Diafine using a Jobo processor. That seemed pretty wild to me because I’ve mostly used Diafine as per directions: 3 minutes, 3 gentle inversions per minute. With a Jobo, you get constant agitation. And the time in each bath was 4 minutes. I had to try it. I do own a Jobo processor, but it’s in need of a lot of repair. It’s in the pile of “fix it up some day” at the moment. But I can provide constant agitation myself.

Double-X at 1600 in Diafine 4+4, constant agitation using stick agitator. Leica M4 and 35mm Summicron IV.
So the son and I took a weekday trip to the American Museum of Natural History, which is one of our favorite places and I’ve also documented here and here and here, and I shot a roll of Double-X at 1600. Later that night I developed it in a Paterson tank, using the stir stick agitation method (no inversions). Constant agitation for four minutes in bath A, and same for bath B. Water stop, fix, and rinse/hypo/rinse.

Double-X at 1600 in Diafine 4+4, constant agitation using stick agitator. Leica M4 and 35mm Summicron IV.
The results are neither impressive nor bad. It looks like pushed black and white film, perhaps a bit grainier than is usual with Diafine. I don’t see any particular quality that jumps out as something special, though I’m quite fond of the grain in the extremely overexposed shots like the following two:

Double-X at 1600 in Diafine 4+4, constant agitation using stick agitator. Leica M4 and 35mm Summicron IV.

Double-X at 1600 in Diafine 4+4, constant agitation using stick agitator. Leica M4 and 35mm Summicron IV.
Something interesting in the development chart on the Project Double-X site is the Diafine section. If you don’t know Diafine, you basically develop all films exactly the same way. Instead of adjusting time and temperature in development to push or pull film, you find the right film speed for the film in Diafine. In other words, if you’re going to use Diafine as your developer, you shoot Tri-X at 1600 (their recommendation) or 1250 (mine). Don’t shoot it at 400. You shoot Plus-X at 400 instead of 125, etc. In this chart, using Diafine normally, it gives the film a speed of 640. But if you give less agitation, the film speed is 800. Then if you agitate the hell out of it (as I did in my case), it gives a speed of 1600. What this probably means is that many people contributed to the chart and each has a sense of what they were successful with.
I’m looking forward to playing around with the few rolls I have. I would love to establish a good speed for developing with Diafine (my summer developer), so I’ll shoot a test roll, metering carefully at 100, 200, 400, 800, and 1600 and then doing stock Diafine development. Then I’ll shoot a roll at 250 and develop in HC-110. Then I’ll try not to buy any more Double-X for a while and whittle my large stash of other film down before spending any more money.
Thanks for this write-up. Very helpful as I have recently decided to try Diafine for my pushed Tri-X and DD-X.
Thank you for writing thhis
You’re welcome!