sur les questions de fixage et lavage des pellicules Kodak, un fil intéressant dans le forum galerie-photo
http://www.galerie-photo.info/forum/rea ... eply_55804
et un long message sur photo-net, fort instructif
http://photo.net/bboard/q-and-a-fetch-msg?msg_id=007dXZ
" T-Max Films:
With some films, such as Kodak's T-Max series, fixer capacity
is reduced to one-half of what one normally expect, and fixing times
are extended to twice the usual time, since silver iodide present in
the "high tech" emulsions is resistant to fixation, and
exceedingly insoluble.
In Kodak publication F-32 on T-Max films, Kodak indicates that a
magenta stain may be left in the emulsion with inadequate fixing, and
recommends further fixing with fresh fixer to remedy the problem. The
magenta sensitizing dye is adsorbed to the silver halide (EKC
statement - not speculation) and when the halide is fully dissolved,
the dye is removed.
In some instances, the dye can be removed by treatment with hypo-
clear, which usually contains sulfite or high salt concentrations
which can act as weak fixers in addition to displacing hypo, or with
prolonged water washes.
The "stain" problem isn't whether it will interfere with
variable contrast paper filtration or not, but its indication that
the film isn't fixed properly. "
et le pdf F32 dont il est question dans le message
http://www.kodak.com/global/en/professi ... 32/f32.pdf
il est possible que pour des questions de rationalisation de sa production, Kodak ait utilisé le même colorant dans le support des TriX, voire ait incorporé de l'iodure d'argent dans sa composition, ce que pense certains