Selenium toner diluted in water or fixer remover?

[JamesFromSydney]

I've read a lot of differing opinion on this issue, without finding a simple answer.

Is there a consensus on diluting selenium toner in water vs. HCA/Washaid ?

I'm primarily interested in toning for archival permanence. The Ilford paper documentation on optimum permanence (I'm using mgiv fb and multigrade dev) suggests dilution with washaid, but their selenium toner documentation oddly doesn't mention it.

I'd also prefer to reuse working solution, which I understand is better done when the stock is diluted with water.

If I dilute with water, should I just add five extra minutes of washing after with HCA / washaid ?

[Jim Noel]

I use Ansel's method. Fix twice>selenium toner diluted with water>rinse>washing aid>wash.

[Gem Singer]

Assuming its Kodak Rapid Selenium Toner, if diluted with distilled water, the toner solution can be used over and over again, until it reaches maximum capacity and is no longer effective.

KRST has ammonium thiosulfate (rapid fixer) in its formulation. HCA is sodium sulfite (anti-oxidant). The purpose for using HCA as a follow up bath after toning is to neutralize the acidity of the ammonium thiosulfate, allowing the rapid fixer to wash out easier.

If the KRST and HCA solutions are mixed together, the effect of the KRST will be reduced and its life expectancy will be shortened.

Either way, wash completely after the HCA bath.

[Greg Blank]

I have answered this question many times, specifically when I was answering questions related to Forte papers. Forte was by far much more sensitive to Selenium than are the Ilford papers. That stated, Forte would produce rather stange anomalous issues with Selenium. I find that the majority of papers work best if you never go from fixer to wash and then to toning. That includes water bath storage.

Always even if only briefly, go back and place the prints into a fix bath. My preference is to fix all prints in a first fix bath, water storage until the end of printing and then refix again just prior to toning, then wash. I also prefer to mix the Selenium with HCA, but I only mix enough for the batch being toned, that is usually 64 oz or apprx 2 litres. Then I discard the HCA- Selenium. If it was Gold toner, I would probably use distilled water, which is what you could do with the selenium and leave the HCA for afterwards. If you use tap water with the selenium you run the risk of discolored areas in the print if your water is trending towards acidic.

[Doremus Scudder]

I have to chime in here...

I, too, have posted frequently on this topic. There are a couple of issues to address here: capacity differences and environmental concerns.

First, a wash aid like Hypo Clearing Agent has a much smaller capacity than the same volume of selenium toner, even at a very weak dilution. Furthermore, dumping selenium toner down the drain (or wherever) that still has a lot of life left in it is not only wasteful, it is environmentally unsound. Of all the photo chemicals we use, selenium is among the most dangerous. It is a heavy metal and is not removed in waste-water treatment plants.

I replenish and re-use my selenium toner solutions and rarely have to discard any (search for my posts on this if you are interested in the details). At the very least, the toning solution should be used until toning times become quite long, and then left overnight with a few scrap prints in it to scavenge more of the remaining selenium before discarding the solution. This will always be long after the capacity of the wash aid is reached. Using the toner past the HCA capacity is certainly possible, but then why mix them together in the first place?

Mixing your toner with a wash aid like HCA, and then discarding it when the capacity for the wash aid has been reached means that you are tossing lots of selenium down the drain that should not be there and could be used for toning more prints. Back in the days when people were less aware of and concerned about poisoning the environment, this may have been an accepted practice. Today it is simply irresponsible. I'm sure if Ansel Adams were alive today, he would no longer recommend this practice.

I recommend mixing your selenium toner with water, using it to exhaustion before discarding or, as I do, replenishing it for future use. The wash aid should be mixed separately and used as a separate step after toning.

Best,

Doremus Scudder

[Greg Blank]

I think this is very valuable information, so after looking at your site....your name is
truely Doremus? All this time I thought it was a sudo name Not so?

I have to chime in here...

I, too, have posted frequently on this topic. There are a couple of issues to address here: capacity differences and environmental concerns.

First, a wash aid like Hypo Clearing Agent has a much smaller capacity than the same volume of selenium toner, even at a very weak dilution. Furthermore, dumping selenium toner down the drain (or wherever) that still has a lot of life left in it is not only wasteful, it is environmentally unsound. Of all the photo chemicals we use, selenium is among the most dangerous. It is a heavy metal and is not removed in waste-water treatment plants.

I replenish and re-use my selenium toner solutions and rarely have to discard any (search for my posts on this if you are interested in the details). At the very least, the toning solution should be used until toning times become quite long, and then left overnight with a few scrap prints in it to scavenge more of the remaining selenium before discarding the solution. This will always be long after the capacity of the wash aid is reached. Using the toner past the HCA capacity is certainly possible, but then why mix them together in the first place?

Mixing your toner with a wash aid like HCA, and then discarding it when the capacity for the wash aid has been reached means that you are tossing lots of selenium down the drain that should not be there and could be used for toning more prints. Back in the days when people were less aware of and concerned about poisoning the environment, this may have been an accepted practice. Today it is simply irresponsible. I'm sure if Ansel Adams were alive today, he would no longer recommend this practice.

I recommend mixing your selenium toner with water, using it to exhaustion before discarding or, as I do, replenishing it for future use. The wash aid should be mixed separately and used as a separate step after toning.

Best,

Doremus Scudder

[paulr]

I was also taught that selenium is a heavy metal, but it isn't; it's a non-metal element that's chemically quite close to sulfur.

It's found naturally in the soil in trace quantities and is an essential nutrient. In higher concentrations it becomes a mild toxin, and in large concentrations a much worse toxin.

I can't find any good information on what happens to it in the wastewater. I gather that it isn't eliminated in any way by sewage treatment, and that some cities and states have set caps on selenium concentrations that can be released from sewage treatment plants.

It seems like a generally good idea to keep as much as possible from going down the drain. But I still gather that silver ions are a bigger problem, both fundamentally and because we produce them in greater quantities.

[Greg Blank]

Long ago I was dedicated to becoming a geologist, to be precise in elementary school. I took the study of rocks so seriously that my fellow students laughed at me and called me a rockhead. When I discovered girls I dropped the rocks. Too bad since gasoline is what 4.00 a gallon and a good geologist could make what 100K + a year.....maybe there is a mother lode of undiscovered petrol- but hey screw U all- to those fools

After many years of toying with ways of being cool, I ended up being a photographer. My first journey west included the Sunshine mine when I was 8, where I was given a sample bag of silver ore as a result of not being able to tour the mine on an off day. The Sunshine mine was where a very bad, accident occurred and miners died inside the mine. http://en.wikipedia.org/wiki/Sunshine_mine. My parents fostered my interest in minerals that way with trips to places I could collect stuff, up until I was about 14, I was really interested in science versus sports.

I want to say selenium is related to gypsum, talc and asbestos you just never know. Like limestone is a calcite deposit which can be derived from plant materials through metamorphing and asbestos then metamorphs from the limestone to serpentine as alumina silicated compounds bind with the base material?




http://en.wikipedia.org/wiki/Selenium

http://www.google.com/imgres?imgurl=...w=1420&bih=899

I was also taught that selenium is a heavy metal, but it isn't; it's a non-metal element that's chemically quite close to sulfur.

It's found naturally in the soil in trace quantities and is an essential nutrient. In higher concentrations it becomes a mild toxin, and in large concentrations a much worse toxin.

I can't find any good information on what happens to it in the wastewater. I gather that it isn't eliminated in any way by sewage treatment, and that some cities and states have set caps on selenium concentrations that can be released from sewage treatment plants.

It seems like a generally good idea to keep as much as possible from going down the drain. But I still gather that silver ions are a bigger problem, both fundamentally and because we produce them in greater quantities.

[JamesFromSydney]

Thanks for the responses. It seems that there are good arguments for diluting with water, and apparently none for diluting with HCA.