Sellective Latent Image Bleaching

[eclarke]

Ken turned me on to this article last year and I have been using this method for undeveloped negs and persulfate bleaching for developed negs, the latent bleaching is really good. You need to get a handle on each emulsion though, some go really quickly and some are very stubborn....EC

 

[dancqu]

[QUOTES=pentaxuser;509789]
"While it seems to be more targeted to using a high contrast
grade to retain punch and still getting shadow detail a la the
young lady on beach, ..."

It would seem that the ferricyanide is progressively
more effective as density increases. That lowers the
contrast in shadow areas. Likely some other lower
grade, Graded or VC, would do depending upon
the negative and degree of SLIMT correction.


"...my conclusion was that in the case of a featureless sky,
you expose for sky detail, getting this right then use the Selective
Latent Image Bleaching to restore details to the foreground which
otherwise would be very dark and even almost featureless black
depending on the difference in the correct exposures for the
sky and foreground."

No doubt some trial and error is involved and the novice
will be a few hours getting the hang of it. Balancing exposure
with post exposure frerricyanide treatment with the correct
grade of paper will be a balancing act. So, although there
is little to the procedure it's correct application may be
a hurdle some will not care to jump. Dan

 

[MurrayMinchin]

No doubt some trial and error is involved and the novice
will be a few hours getting the hang of it. Balancing exposure
with post exposure frerricyanide treatment with the correct
grade of paper will be a balancing act. So, although there
is little to the procedure it's correct application may be
a hurdle some will not care to jump. Dan

Exactly like doing zone system tests for minus negative development. (It makes the most sense with sheet film or if you have a seperate camera backs for each different development regime).

The beauty of developing negatives using SLIMT is that after the weak bleach step the negative gets developed for the same time and at the same dilution as normal negatives. This means for example that four normal negatives can go in the pre-soak, two -2 negatives get the -2 SLIMT treatment, then all six can be developed together...a HUGE time saving perk.

Can I mention again that SLIMT is for negatives and the Sterry Method is for prints. The bleach step works the same in both methods, where its effect is proportionaly greater as density increases...but much confusion will arise if one person is talking prints and the other is talking negatives!

Murray

 

[dancqu]

Can I mention again that SLIMT is for negatives
and the Sterry Method is for prints. Murray

The Serry method uses, IIRC, potassium dichromate.
I'm quite sure Mr. Kachel has replaced that with potassium
ferricyanide for both film and paper. Also I do not recall any
other instance of the Sterry method being used with film.
My understanding is that either chemical can be used
but the advantages favor ferricyanide. Dan