monobath-stand-developer-fixer-exhaustion

[neelin]

Monobath
Stand development
Developer exhaustion
Fixerexhaustion

Was pondering the combination of these concepts. Stand development capitalizes on limiting blocking of highlights by developer exhaustion at denser areas. If a small amount of fixer was added to the developer in stand development, it would aid in reducing blocking of highlights by finishing off the dense areas, while the opposite exhaustion, fixer exhaustion would take place where there was little exposure, allowing developer to continue working. I suspect initial 60 second common agitation at the onset would have to be reduced, and for sure absolute stand development.

Any other warped minds finished with this idea & put it in the trashbin yet?

robert

 

[David A. Goldfarb]

In a monobath, development time is affected more than fixing time by temperature, but fixing time is affected more by agitation.

If you look up the long monobath thread, where I discussed a number of my own tests, I think I posted at some point that I thought it was good to use low agitation at the beginning during the (mostly) development phase, and more agitation later during the (mostly) fixing phase.

You could tweak the variables of temperature and agitation, I suppose, to create different effects. Bear in mind that silver plating out onto the neg during the fixing phase will increase highlight density.

 

[Ian Grant]

Monobaths are less susceptible to changes in temperature & agitation, because as you increase/decrease the rate of development with either you also change the rate of fixation which is counter productive. As David knows Monobaths are notoriously finicky and in reality it's best to tweak a formulae to suite a particular film.

If you want to add a small amount of Fixer to a developer then look at Kodak DK-20:

DK-20

Metol 5g
Sodium Sulphite (anhyd) 100g
Sodium Metaborate (Kodalk) 2g
Sodium Thiocyanate 1g
Potassium Bromide 0.5g
Water to make 1 litre

DK-20 went out of general use because the Thiocyanate caused Dichroic fogging with some films, you could try replace it with a small amount of Sodium Thiosuphate (Hypo) 2-4gms.

Alternately add 25g of Sodium Chloride to Kodak D-23 this gives a developer similar to Microdol-X/Perceptol, the Chloride acts as a restrainer/silver solvent.

Ian