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To see the images from my various test rolls, check this Flickr album.

To hear about this mini project in video form, check this YouTube video.

Tri-x '74 is the colloquial name I've given to a batch of three tins of Kodak Tri-x 400 which expired in 1974. 

It is a black and white negative film, but development may require more care than you think. The film is extremely heavily fogged due to age, so negatives appear rather dense and "flat", lacking contrast. Technically, DMax was good but DMin was poor.

According to the "add one stop per decade of expiry" rule of thumb, which is largely nonsense anyway, this 48-year-expired film should perform best when rated at ISO (technically EI, exposure index) 12.

I shot a ten-exposure test roll, bracketing my shutter speed to rate the film at a different EI for every shot. Starting at 800, I moved one stop at a time down to EI 1.5. the roll was developed for EI 400 (details below).

Honestly, I was amazed that there was an image at all.

2022-06-28 TriX74 exponential test_ei100.jpg

EI 100, HC-110 (1+100, 60:00, 20 °C,

exponential agitation)



Honestly, giving the film more light doesn't change things too much. The negatives have slightly more contrast when rated at EI 12-100, but despite EI 12 being the expected "right" way to shoot the film, the shots taken at EI 12, 6, 3, and 1.5 are extremely flat by comparison, becoming progressively harder to extract an image from due to their extreme density. I personally like a high-sharpness aesthetic for grainy film, but you may not.

This test basically proved that there is a limit to "overexposing above the fog", if that was ever in question.

Here is an unedited shot at EI 12 with no editing beyond inverting it to a positive, for reference.


EI 12, HC-110 (B, 6:30, 20 °C)


For my initial test roll the development conditions were as follows:

Developer: Kodak HC-110 (chosen for its characteristic curve)

Dilution: 1+31 (dilution B)

Temperature: 20 °C

Time: 6:30

Agitation method: Continuous inversion for first minute followed by four inversions for the first ten seconds of each subsequent minute.

This method yielded the Radox soap image shown above. Images show even and complete development, but the grain pattern is unappealing and the fog is pronounced.

I have tried a range of methods since. In brief:

- HC-110 Dilution F, 15:00, 20 °C

- HC-110 1+100 stand development, 60:00, 20 °C

- HC-110 1+100 semi-stand development, 60:00, 20 °C

- HC-110 1+100 stand development, 60:00, 20 °C, 3 drops of 1% w/v benzotriazole

- HC-110 Dilution F semi-stand development, 60:00, 20 °C

In carrying out these tests I was able to discern that the fog and overall grain structure improve with longer development times and more dilute developer. This may be due to the characteristic curve of HC-110 "preferring" development of the latent image over the fog working synergistically with the dilute working solution and low level of agitation. 

A major problem I had was that while the stand-developed methods looked pretty good in terms of fog and grain, they suffered from tremendous levels of bromide drag, far beyond what I had ever seen in any other stand development dev run. However, there was a usable image right at EI 400 - box speed!

2022-02-27 XPanII TriX74 4.jpg

EI 400, HC-110 (1+100, 60:00, 20 °C, stand developed)

I carried out one final test using my friend Golf's "exponential agitation" method, and it worked both perfectly and reproducibly!


Developer: Kodak HC-110

Dilution: 1+100

Total volume: 500 ml

Temperature: 20 °C

Time: 60:00

Agitation: "Exponential agitation"

The "exponential agitation" method is as follows. Note that inversions are required, not simple swizzle stick agitations.

- Invert the tank continuously and slowly for the first 30 seconds

- Invert the tank once at 1:00

- Carry out one further inversion each at 2:00, 4:00, 8:00, 16:00, and 32:00

It is likely that further modification to omit certain agitations from the method would improve image quality further, but honestly, I've used a full tin of this film for testing already and I'm happy with the results that I'm getting. EI 100 is absolutely usable, and overexposing further to EI 50 or 25 doesn't improve the image quite enough to justify the loss in (effective) film speed, to me.


Thanks again to Golf for the help with this. check out his Flickr for similar experiments, and several that go far beyond the scope of my own abilities, such as his C-41 reversal experiments:

2022-06-28 TriX74 exponential test_ei100.jpg

EI 100, HC-110 (1+100, 60:00, 20 °C, exponential agitation)

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