[Alt-photo] salted paper
daniel at danestabrook.com
Fri Apr 29 13:01:52 UTC 2016
Looking at your student's print, I will say with 99% certainty that it is simply a coating issue, and not any silver chloride build-up. (I mean, if it was AgCl building up at that point in the print, wouldn't it "drag" throughout the rest of the coating...?)
Note that when I say the ratio of salt to silver is key, that it is not always too much salt in the first layer that causes problems—it can also be too little silver! This is what I think is happening here. I would guess that your (likely right-handed!) student dipped the brush in silver and started coating from the top left (either horizontally or vertically) and changed directions for another pass, after dipping the brush once again. In either case, by the time the brush got to the middle-right of the paper, it was too dry. Look at the difference between the top-left corner and the bottom right and note the density difference. To fix this, just make sure to dip more often, say at the start and at the halfway point of an 8x10 print, and again when switching directions. Really, you want as much silver on there without causing pools of excess (another problem entirely!)
Some people are just more heavy-handed than others. You may already note the students who flood the paper and get silver everywhere, and the others who work in tiny little careful rectangles. One tip: even if a student wants to make small 4x5-ish prints, have them coat a larger piece of paper and cut it down; it's much easier to make a smooth coating with a little room to work.
> You are saying that these areas of white are an excess of salt in that area in comparison to silver, which is much less sensitive. Schaefer is saying it is disturbing the salted layer when sensitizing (e.g. brushing too firmly or whatnot) so it mingles with the wet silver nitrate to create this silver chloride “smudge."
> Here’s my conundrum: I uploaded a student print here: http://christinaanderson.visualserver.com/Text_page.cfm?pID=6523
> which shows a very visible brush streak the exact size and width of my 3” hake brush. I don’t use that hake brush to salt the paper, so it’s not the sizing step that places too much salt there. If I understand correctly there would be excess salt in that particular sharp shape of brush stroke if he brushed so hard there was less remaining silver in that spot, which in essence increased the salt to silver ratio.
> But it still seems odd that the unevenness of silver in that spot wouldn’t be visible with the blue food coloring. Gray, btw, and Schaefer, did the coating with cotton stuffed in a test tube thing on a plexi sheet at a 45º angle to avoid this issue.
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