Visit my new blog

I´ve decided to split my blog in two. I will continue to post DIY projects and musings here, but (serious) pictures, taken on film of course, will be posted in my new blog "Silver Halides"

I now consider Caffenol to be a developer like any else. As such the new blog will focus more on the pictures, rather than the process.

Thursday 6 September 2012

Kodak Tri-X (TX400 or 400TX) in Caffenol-C-H

I´ve recently developed two rolls of Tri-X. Both over expiry, one of the previous emulsion, and one of the current. Both worked out well.

Tri-X has always been Tri-X. But look at the designation on the box, and on the film rabate you´ll see that indeed they are different. Modern (post 2007) Tri-X is called 400TX. The former emulsion is called TX400 or just TX. Reputedly the newer emulsion is more fine grained and requires shorter development. Finer grain? Possibly, not that I would fret over big fat grain on the older version, if I was so lucky to find a cache. It´s still very good in Caffenol. I did however develop the two films (very) slightly differently.

Modern Tri-X, exposed at EI400, in Caffenol-C-H(RS) and 0.7g/l of Potassium Bromide (KBr). A small recap of the RS recipe bottom of post.

14 minutes and 30 seconds @ 20C/68F. 12 initial inversions, and 3 every top of the minute as usual, save the last at 14 minutes (i.e. stand from 13 minutes). Water stop, 1 minute. Normal fixing and washing. All at as close to 20C/68F as possible.

Modern Tri-X, box speed, Caffenol-C-H(RS), 14m30s @ 20C. DIY 6x17 Camera
Modern Tri-X, box speed, Caffenol-C-H(RS), 14m30s @ 20C. DIY 6x17 Camera
Click on the pictures, they are large and you will see just how good Tri-X can be. I really got lucky on these. Shot with my DIY 6x17

A prior attempt to expose a roll of Trix met with just about every problem in the book. Firstly the back on the Super 66 has developed a light leak. Luckily the frame shown below, and the first frame are exempt from damage, all the others are not.Secondly the first 5 frames of the film, all have a dark lower 1/4. Why is a mystery. Again this frame went clear.
Thirdly the self timer switch on the leaf shuttered lens got engaged without me noticing. Once I thought I had the shot in the bag (the mirror swinging up makes a loud kaaawhuump) and I started to walk away I heard the dreadful sound of the timer clockwork. I rushed back and reframed blind (the mirror was still up of course, obscuring the view, so why am I looking into the viewfinder?). And better framing than this is difficult even with finder. Missed the focus by a foot though. So now my reflection is more in focus than I had hoped. Ah well, that´s Sod´s law I suppose.
But back to business. This is the older emulsion, and yes there is slightly more grain, but still very good for a 400 speed film. Tonality is good. Due to the problems with exposing this film, the example frame is not the best.
Again, Caffenol-C-H(RS), this time with 1.2g/l KBr. All else equal.
Old Tri-X, box speed, Caffenol-C-H(RS), 14m30s @ 20C. Kowa Super 66 w/150mm f3.5

Caffenol-C-H vs C-H(RS)
In a 1 liter solution, each:
Sodium Carbonate, anhydrous 54g - 40g
Ascorbic acid 16g - 16g
Instant coffee 40g - 40g
Potassium Bromide (KBr) whatever, same for both. Between 0.6 and 1.5g/l depending on emulsion.

As you can see, only the amount of soda (sodium carbonate) is reduced. This lowers the pH, makes the developer less active. My experience says it´s still active enough. I haven´t really adapted my times much.
Benefits over regular C-H (same applies for C-M(RS) over C-M). I find grain is slightly less pronounced, and the tonal gradation is smoother, slightly less contrast maybe. 
With regards to the two Tri-X versions. Both are perfectly good films. I´ve already ordered a couple of bricks of modern Tri-X. ;)

2 comments:

  1. I would like to develop an roll of TRI X with Caffenol C. STD.
    150ml Water, 6 rounded Teaspoons Instant Coffee (15 grams)
    200ml Water, 4 leveled Teaspoons Washing Soda (8 grams)
    Mix all together, add 1 Teaspoon of Vitamin C (7 grams)

    Do you think I should stick with 14 min of development?

    Looking forward to hear from you.

    Kind regards.

    Julius

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  2. Julius, no one is able to tell you what should you use because you measure with spoons so it is impossible to state how your developer will work.
    For consistent results you have to measure with scale (buy cheap electronic one on eBay or elsewhere) and use pure ingredients. Otherwise you can no bother about development times ;-)

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