Category: the Lab

Mixing Kodak Tanning Developer

Posted on Posted in dye transfer, How To, the LabTagged

adage: mix for 4, use for 3

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To make a set of mats, expose them and set aside the three mats in a safe-box. To develop, use the mixing directions, amounts as though you were souping 4 mats, but use that mixed developer in thirds. Take 1/3 and develop each mat in your developing tray. This assumes a very standardized procedure that has controlled balance and contrast. Clearly, if you are processing mats to different contrasts, then you cannot develop using the same mixed working solution.
Time is not a good adjustment to matrix contrast change. Tanning of the gelatin does not occur directly with development time. The oxidation of the tanning developer does not affect the matrix tanning as much as it would intuitively seem. The experienced darkroom tech coming to dye transfer cannot wholly bring their prior B&W experience to the matrix phase of dye transfer.

dye transfer

the matrix is the matrix — another world with other meanings

Sadly, none of this instruction will be useful to you these days, since none of the Kodak materials are useable. Any matrix film you could find is too old for proper dye transfers. They will have ‘age fog’ of the gelatin itself. Even if using the Efke film (sponsored by Jim Browning)it is so old that I wouldn’t use it as a reference to dye transfer from the age when fresh supplies were available in great quantity.

Even the most recent incarnation of Matrix films (Gecko, and Del Rio), which were being made when this post was originally made (2014), are out of production(2018 was the last date).

some links to formulas: Tanning Developers …& … PRIVATE page

Old Matrix Film

Posted on Posted in dye transfer, the LabTagged

gelatin hardens as it ages. And it does so in an uncharacterized manner. As the gelatin of a matrix film ages, it undergoes changes which I don’t know have ever been studied. No reason to do so since no film maker ever thought people would store soft gelatin film for decades.
Most of those still making Dye Transfers are doing so with old matrixfilm. They are hoping that cold storage is extending their working years, but how long is it useable? The following table presents some results of testing that I performed last year using matrixfilm I have gotten from many sources. I do not know the real storage condition of the materials, but everyone claimed their matrixfilm had been stored correctly since they bought it.
What is good enough?
Can it produce a mat that can hold Kodak dyes, and transfer completely, providing a full range of tones — simple, right.
As the matrix film ages, it hardens on its own. It does this based on size of the sheet, temperature of storage, and something else — I don’t know what, but I suspect that it is the sensitizer used during the coating of the emulsion. The more senisitive to broader spectrum, the quicker the matrix suffers from “hardening of the storage” — ortho last longer than panchromatic — smaller sheets last longer than bigger. Zoing.

Once you process the matrix it can be stored, seemingly indefinitely– just don’t “poison” the mat and it will last as long as any film (my guestimate). If the gelatin hardens it can readily be softened enough to pull prints. This has been confirmed by pulling mats that were first exposed circa 1974.