Using expired paper, where to start

[Greg]

Have acquired several boxes of very expired enlarging paper. Dates on boxes 1980s and 1990s. Storage conditions unknown. Want to use them, so I figured I'd start with exposing a sheet from each box with a step wedge and process for a normal development time. The gray scale showed me the D-max and D-min of he paper. Surprisingly most sheets from most boxes are possibly useable (gray scales a start) but with some sheets (boxes) there is a little bit of "fog" density in the highlights. Way back in the 1970s vaguely remember adding some chemical to the developer to have the whites come out pure white, but can't remember what I added to the developer. Other option I've used in the way past was to ever so slightly bleach prints in a very weak solution of potassium ferrocyanide after the fix. Don't remember how I stopped the bleaching action, possibly returning the paper to the fixer - I believe W. Eugene Smith did this when he was selectively bleaching parts of his prints.

All my notes as to using expired paper long last lost or thrown away.

Does anyone out there have any advice?

[Leigh]

anti-fog is Benzotriazole

- Leigh

[Doremus Scudder]

Greg,

Do a search here on antifoggants/restrainers. There's a lot of info on them.

Most commonly, people use potassium bromide (KBr) or benzotriazole (BTA) to combat paper fog. BTA is about 10x more active than KBr, so it's fairly common to use a 10% solution of KBr and/or a 1% solution of BTA. BTA will cool the image tone a bit and help contrast slightly; KBr warms the tone.

Start with 2-5 ml per liter of 1% BTA or 10% KBr to combat fog (or an equivalent combination of the two). Increase this in similar increments until you reach the point of no fog or have added 20-50 ml/liter of your solutions. After that, you are likely not going to get rid of the fog with a restrainer/antifoggant. The idea is to use the minimum amount needed. You'll have to compensate with added exposure since the restrainer/antifoggant slows down the paper speed.

If the restrainer/antifoggant won't do the job completely, you can clear the whites in a weak bleach solution. I like a rehalogenating bleach of potassium ferricyanide and KBr. I start with a 1% solution (1g pot. ferri and 1g KBr /liter) and strengthen/weaken from there. The goal is to get the whites clear in a workable time without overbleaching. Make sure the print is free of fixer by washing in running water for at least five minutes. Immerse in the bleach and watch carefully. Having a comparison print or fixed but undeveloped paper white strip handy to compare to helps a lot. Pull the print just before bleaching is complete and transfer to a running water bath. You may find you have to print a bit heavier to compensate for the bleaching action in the mids and shadows. After bleaching, refix the print and wash as usual. Refixing is necessary since silver in the print is rehalogenated into silver bromide and needs to be fixed and washed out.

Hope this helps,

Doremus

[LabRat]

A big issue that comes up when using old baryta based papers is that while developing, different patterns of staining (usually blue) comes up through the paper base, particularly where the paper bends, or tongs make pressure on the borders... I've always surmised that it possibly has something to do with with the base having some kind of "soak-through" where the bending or pressure allows moisture to completely penetrate at those points... Sometimes the paper base starts at total white, but as the process goes on, the staining increases, and by the time in the wash, too much staining... It might be that the base gets too dried out, and bending while wetting causing cracking that allows the "soak through" in those areas...

To minimize this effect, it is best to keep dry to dry times to a minimum, keep paper from bending during process, use wide borders that can be cut away with the tong marks areas, and try not get too mad when this keeps happening during printing, because it's the nature of the beast...

Steve K

[koraks]

I start with a 1% solution (1g pot. ferri and 1g KBr /liter)

1 gram per liter (1000 cc) is 0.1%, right?

[bob carnie]

You may want to try Lith printing or experiment with Lumen prints, both beautiful silver processes that like old fogged paper.

[tgtaylor]

1 gram per liter (1000 cc) is 0.1%, right?

Right! Why? Because (10/1000)*100 = 1.0%.

Thomas

[jnantz]

You may want to try Lith printing or experiment with Lumen prints, both beautiful silver processes that like old fogged paper.

+1 !

[tgtaylor]

Right! Why? Because (10/1000)*100 = 1.0%.

Thomas

If you know a little elementary algebra you can solve future similar problems like this:

(X/1000)*100 = 1
100X = 1000
X = 1000/100
X = 1

Thomas

[Tin Can]

If you know a little elementary algebra you can solve future similar problems like this:

(X/1000)*100 = 1
100X = 1000
X = 1000/100
X = 1

Thomas

Really?