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bowzart
12-14-2008, 04:20 PM
Use standing-water wash baths as much as possible.

Vaughn

Vaughn, David, and any others with insight into this -- How do you use standing water baths? Several sequential? How long? And how much running water after? Any pointers?

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Water is one problem, but what the water carries is important, too. Wherever we live and work, effluent is an issue. Here, there is a likelihood that fixer's silver content will end up in the bodies of those yummy oysters that they farm around here. Since I eat them, I have a certain vested interest. In another place, like Utah, there may be no oysters (there used to be, how many millions of years ago?) but something else will end up with it. So, everywhere, it is very important to drain the fix off the prints thoroughly before washing, and dispose of the used fixer responsibly. I've thought of plating it out; I'm sure Hallmark Precious Metals would happily accept small gifts of flake.

The metal isn't the problem; ions are the problem. At one of my past schools, they redesigned the facility, leaving out the recovery system. The state came in and forced them to add one. At another school, we had to add steel wool cartridges. The refinery sold us the unit, then we paid off the balance in small amounts of silver over time whenever they picked up a cartridge.

Larry

JBrunner
12-14-2008, 04:28 PM
Vaughn, David, and any others with insight into this -- How do you use standing water baths? Several sequential? How long? And how much running water after? Any pointers?

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Water is one problem, but what the water carries is important, too. Wherever we live and work, effluent is an issue. Here, there is a likelihood that fixer's silver content will end up in the bodies of those yummy oysters that they farm around here. Since I eat them, I have a certain vested interest. In another place, like Utah, there may be no oysters (there used to be, how many millions of years ago?) but something else will end up with it. So, everywhere, it is very important to drain the fix off the prints thoroughly before washing, and dispose of the used fixer responsibly. I've thought of plating it out; I'm sure Hallmark Precious Metals would happily accept small gifts of flake.

The metal isn't the problem; ions are the problem. At one of my past schools, they redesigned the facility, leaving out the recovery system. The state came in and forced them to add one. At another school, we had to add steel wool cartridges. The refinery sold us the unit, then we paid off the balance in small amounts of silver over time whenever they picked up a cartridge.

Larry

In the Salt Lake Valley, everything winds up in The Great Salt Lake, which has an unprecedented amount of mercury in it as well as almost any mineral salt you can name. If you evaporate a cup of water from the GSL you will have up to 30% mineral content, depending on the part of the lake you pull from.

The lake itself only supports brine shrimp, algae, things like that, however the brackish marshes around it are important habitat for migratory birds, and other creatures.

Vaughn
12-14-2008, 05:22 PM
Larry -- I am a bad water-waster (except during those rare drought years). But I go with 5 changes of water at about 5 to 10 minutes each (with occasional aggatation to reduce the concentration of chemicals next to the paper/film). My only running water bath would be the first one (short -- maybe a minute) -- to get rid of any fixer on the surface. This is what I used for film washing (8x10) before I got my film hangers. I'd develop 5 negs at a time and put each neg in its own 8x10 tray to wash.

We have a large oyster farm operation here in Humboldt Bay -- I don't eat too many (very few, actually) -- it is dioxin that is a worry here. But I did have some wonderful wild ones in Australia the last time I was there (from some river mouth up in northern NSW.)

Vaughn

bowzart
12-14-2008, 08:29 PM
... I go with 5 changes of water at about 5 to 10 minutes each (with occasional aggatation to reduce the concentration of chemicals next to the paper/film). My only running water bath would be the first one (short -- maybe a minute) -- to get rid of any fixer on the surface.
Vaughn

Thanks.

Hmm. I am surprised. I would think that the running water bath would have be the last one, or that there would be a short one to begin, and then a few cycles of soak, then a final one. It would seem to me that the final one would be the most critical.

My rationale would be that when you place a piece of paper containing fixer in a tray of water, the paper will yield up its fixer to the water, turning the water into very dilute fixer. Then, if you dump that, replacing the water, you would get a yet greater dilution, etc. Of course, we're talking here about fiber paper; RC requires very little wash because the paper is sealed in plastic, and except for the very edges, isn't soaking up fixer at all. Film also. What I have always heard is that film and RC CAN be washed clean, but fiber paper can never really be completely free of fixer. The level can only be reduced to a very low level.

The way it was explained to me long ago was that it is analogous to the half-life of radioactive materials. After a certain time in the wash, time not specified, half of the fixer would be gone. After that same time again, half of the remaining fixer would be gone. After that same time again,.... infinite regression. I started in this business when there was ONLY fiber; RC had not been invented (well, there was a little "waterproof" paper the military used). The time in a running water wash was always 1 hour. Wash was absolutely HOLY. Not ever to be violated. Last print in, the time starts; no prints to be added until all the clean ones were taken out.

I'm pretty conservative about the wash, which means I'm not conserving much water and I'd really like to change that, I really want to use less water. So, I've become religious about Permawash. I would think that we could cut MOST of the fixer with a few standing soaks, but I really doubt (could this be a product of my extremely rigorous training? Am I overdoing it?) that without a final running water wash, there would just have to be some significant amount left. Everything I've ever read in my ancient library (some of the photo books were saved when the library at Alexandria burned, and they all came to me) said that it was the NUMBER OF COMPLETE CHANGES, not the time in the water, that actually washes. This makes sense to me.

Seems to me I recall you using a residual hypo test - or was it somebody else? If you do, what color do you get?

___

Too bad about the oysters. One of the local tribes up here is conducting a study of the effects of the pollution. The coastal tribes' traditional diet was very heavy in shellfish, and they are concerned about the long term effects over a whole lifetime. What to feed the children? We lived in the hamlet of Edison on Samish Bay for five years. Sewage from the town was simply dumped into the bay when we arrived in 1997. Community activists got a project going to construct a local sewage district, which we are still paying off on a zero percent loan from the county. When the project was completed, a very large additional area in the bay was opened for oyster production. I don't even know how many oyster companies there are. Quite a few.

David A. Goldfarb
12-14-2008, 08:38 PM
For prints, when I do the standing bath wash, I usually do about seven changes of water in progressively longer baths, like 1', 3', 5', 5', 10', 10', 15', depending on what exactly I'm doing. I might do less than that when I'm washing fixed prints and use Permawash. For pre-washing albumen prints before toning (the sequence is print out under UV/sunlight, prewash, tone, rinse, two-bath fix, wash), I wash until there is no more milky silver precipitate coming off the prints.

I've started doing silver reclamation with my fixer, using the simple steel wool method. I don't know what I'll do with the sludge yet, but I figure I can accumulate it for several years before I have to decide, and meanwhile, I won't be putting as much silver into the waste water.

Vaughn
12-14-2008, 09:41 PM
"Seems to me I recall you using a residual hypo test - or was it somebody else? If you do, what color do you get?"

Somebody else, I guess. The point is, that running water does not increase the rate of which chemicals leave the paper. The rate of diffusion between fresh, running water, and the water of the 5th bath is probably not significant, since the concentration of chemicals in the 5th bath is so low (if the concentration is so low that it can not be found in testing the water, then the same will hold with the paper.). So if one ran a running water bath after the 5th standing bath, one might as well just do instead another standing water bath in place of the running water bath.

And while I did not mention it, I do a one minute rinse in running water after fixing, a tray of Kodak HCA, then a minute running water rinse, then start washing.

Vaughn

JBrunner
12-14-2008, 10:03 PM
I

I find it interesting comparing the SLC rain data I linked to above, and the perception of those who live there. I suppose even if SLC gets an inch of rain every month, when it is such low humidity it must evaporate right after hitting the ground and not soak in. So different from here!

Vaughn

The data also probably incorporates precipitation in the alpine altitudes where very few persons (per capita) live. The Salt Lake valley is a desert ringed by mountains, some pushing 11,000 feet. The mountains receive much higher rates of precipitation, including much of the water that evaporates from the valley as the air is forced up the mountains and cooled. In the winter, the heavy snows that result in the mountains from evaporated lake water are termed "lake effect snow".

To illustrate the difference, yesterday we finally got about 4 inches of snow. Snowbird, twelve miles east of me has 96.

Vaughn
12-14-2008, 10:20 PM
That might explain it. But the data below is based at the airport..so it depends on where the airport is, relative to most of the city. I suppose that the summer rains are monsoon thunderstorms which can be quite spotty. And I imagine your winter snows are a bit dry -- low in moisture, so a lot of snow does not equal a lot of precipitation.

Jan...Feb...Mar...Apr...May..Jun..Jul..Aug...Sep.. Oct..Nov...Dec
3.23 4.89 3.97 4.90 4.76 3.84 2.57 3.66 7.04 3.91 3.34 4.37 Record Precipitation in.
1.37 1.33 1.91 2.02 2.09 0.77 0.72 0.76 1.33 1.57 1.40 1.23 Average Precipitation in.

You gotta be careful be careful where the rain gauge is! A local coastal community expanded and many home lots put in, with drainage and culvert sizing determined by the closest official data collection location (Humboldt Bay, which averages 42 inches or so). Shelter Cove, where this project was, in reality gets up to 100 inches a year. To say the least, many of the culverts blew out, and many of the lots ended up in the ocean!

Vaughn

JBrunner
12-14-2008, 10:22 PM
Interesting, the airport is in the low part of the valley, up against the lake. In other words, a dry area.

bowzart
12-14-2008, 10:25 PM
The point is, that running water does not increase the rate of which chemicals leave the paper.
Vaughn

This is really valuable information. Thanks. I'll put it into my mill and see what comes out. much appreciation - as usual.

L.

Vaughn
12-15-2008, 03:16 PM
Interesting, the airport is in the low part of the valley, up against the lake. In other words, a dry area.

I can see this as being a matter of perception of the amount of precipitation. A summer thunderstorm drops a quarter inch of rain in a short period -- the streets are dry, then wet, then dry again within minutes. To those inside at the time, it might have seemed not to have rained at all.

Snow on the other hand sticks around. But it takes (on the average) 10 inches of snow to equal an inch of rain...and this figure for snow can vary from about 3 inches to 30" of snow to equal 1" of rain. So if SLC gets a foot of dry snow, that might be less water (precipitation) than in a big thunderstorm in the summer.

Precipitation measurements are in inches of rain, plus inches of water in the snow (not the depth of the snow).

Today, we have snow flakes coming down mixed in with the rain -- at sea level here in northern CA. I did not ride my bicycle to work today.

Vaughn