Selenium Toning ?'s

[TedW]

Hello,

I'm following a selenium toning processes that requires "pure hypo" but has no recipe for the "pure hypo". I purchased PF 10-1360 sodium thiosulfate in granular form. The process is:

1. Water-for dry prints soak 3 minutes
2. Pure Hypo-3-5 minutes w/agitation
3. KRST solution [1.5 oz KRST, 28 oz water & 1/8 t. Kodalk (I purchased PF
10-1285--sodium metaborate)] 3-10 minutes continous
agitation
4. HCA-5 minutes occasional agitation
5. Wash-30-40 minutes

The prints are on Kentmere Fineprint VC fiber paper processed in PF 130.

My question is what the recipe for the pure hypo mixture?
Does anyone know why the prints should go through pure hypo?
Why would you add Kodalk to KRST?
Is the sodium metaborate the equivalent to Kodalk?

I have not been able to reach the photographer who highly recommended this procedure.

Thank you,
Ted W.

 

[Monophoto]

Let me add one more question - -

what are the purported advantages of this process over the more conventional sequence consisting of fix - rinse - hypo clear - tone - hypoclear wash?

 

[Snapshot]

Pure hypo is sodium thiosulfate. If the formula calls for pure hypo then use sodium thiosulfate. Thus, if the formula calls for 500g of pure hypo then use 500g of sodium thiosulfate.

 

[Vaughn]

From what I understand, one can either selenium tone a print fresh out of the fixer...or selenium tone a print that has been fully washed. Anything in between can lead to staining.

Alkaline solutions (sodium metaborate creates an alkaline solution, I believe) can soften gelatin, so perhaps combining a print fixed without hardener and toned in a slightly alkaline solution will have a nice soft gelatin emulsion and can be penetrated quickly for short toning times.

I just used a weaker 10% hypo solution for salted prints (100 grams Sodium thiosulfate to 1000 ml water). The Darkroom Cookbook gives a formula of 480 grams Sodium thiosulfate to 2000 ml water...which is about a 25% hypo solution.

Vaughn

 

[Les McLean]

Many years ago when Agfa Record Rapid was the popular paper here in the UK many of the printers who used it liked the way it split toned. Some printers would place the print into the selenium toner straight from a fresh fixer solution and claimed that this improved the chance of the split toned effect. I did try it but never felt that it was effective. Perhaps the process that Ted refers too was an old one intended to induce split toning.

 

[Robert Hall]

I concur with Les.

There seems to be some romantic attachment to pure hypo which, by the way, should be the pentahydrate as it dissolves easier in water. With most of the current papers there would be little if any difference in the toning properties. This could change if one used some semi-exotic processes on the papers such as lith printing, but with lith printing the toning happens so fast it would be tricky at best to get repeatable results. (if that is what one is looking for)


As for the formula, one can use just the thio to make the fix. Many have added acids such as boric acid to do a couple things, one is to help eliminate developer carry over as this retards the fixers ability to work and two to work in maintaining shelf life of the fix.

I have seen people suggest using "plain fixer" for years in many different applications and for one reason or another I have found them to be ineffectual.

 

[panastasia]

Hello,

Is the sodium metaborate the equivalent to Kodalk?

Yes