Re: Cyanotype Redux
I think I must, either for lack of information or lack of imagination, have lucked out with cyano, in that I pretty much did everything fine the first time. Tho come to think of it I did try 5 or 6 different paper sizes (as instructed by most of the cyano instructions I came across, when the only info I had was the vintage literature). The only sizes that didn't make a weaker print were the ones using starch. None of them improved the print, however, so I skipped all. A gelatin size (advised in some dumbass advisories, if you'll excuse my French) ALWAYS made a terrible print in cyanotype, which of course saved much trouble -- not having to size. I never heard of a "hake" brush til I began doing gum 6 or 12 months later, and since my local hardware stores both carried the foam brush with the wood handle, which has softer, kindlier foam, that was the kind I used -- again no problem. As for one coat vs 2 coats, I did test that, and so did my students... we found that on most papers the second coat made a worse print, apparently wiping off emulsion. Just one paper did better with 2 coats but I don't remember which. I think it was a junky paper that nobody liked & we dropped it. (This from memory, now cluttered up with other things. But, come to think of it, I put most of this info into P-F #5 -- where it's very handy because I can look stuff up & pretend I knew it all along.) My conclusion on all this, for what it's worth, is that there actually are factors that could change results in cyano. I myself just didn't run into most of them. The one that comes to mind a propos of the troubles cited now, is the wash water... (As someone just said) it could be alkaline, or relatively so. Have folks getting runoff (or whatever) tried a slug of vinegar in the wash? And/or ph strips to test it? But of course the ferric ammonium citrate could be different, we're not using science grade, AND the paper varies, even with the same name (not to mention its age & storage) -- I think I've mentioned that one paper seller (I think it was David Aldera at NY Central) said a customer of his found that her platinum printing went off on paper (I forget which) made in -- one season, I think it was winter, tho it could have been summer (heh heh). So when she needed a new batch of paper, she waited til the correct season, David would order it, she'd take a few sheets to try, while he put the rest aside. If they were OK, she'd buy the rest. If not, I don't know what *she* did, but he could always sell the paper since most folks' process wasn't that temperamental. I think the need for changing ratios of A to B may be related to the scale of the negative--and could be useful/necessary when using same negs for different processes. (My exposures were usually around 8 minutes -- tho the number of bulbs, distance from bulbs, paper, time of emulsion on the paper, temperature/humidity, etc. etc. etc. can all affect exposure time (duh !) .... and EXTREMELY interesting to me, the wait after exposure before development turned out to affect midtone separation. (I'd have to look it up, it could be in #5, but my recollection is that 45 minutes wait was best -- like post-its, discovered by accident.) Oh shucks, I'm supposed to be elsewhere doing something tedious -- shop talk is soooo seductive... Meanwhile however thanks to Brian for the kind words... tho it never occurred to me that runoff could be related to foam vs. hake... (fascinating, don't you think?), I was just thinking how much easier application of emulsion is with foam. Judy On Mon, 3 Mar 2008, Brian Pawlowski wrote: But Judy Seigel sent me a note along the lines of "This is a really simple process. Why are you using a hake brush - use a foam brush. Etc." I went to Home Depot, and picked up a couple cheap black foam brushes with wooden handles. After several back and forth tests, I'm concluding the foam brush outperforms the hake and Richeson brushes for my cyanotypes - I'm getting virtually *no* runoff - whereas before it looked like a Smurf took a bath in the tray. Can it *really* be that simple? The foam brush moves more roughly across the paper surface. Kevin Sullivan in an e-mail sometime back when I made a comment about runoff on COT 320 said it might be necessary to rough up the surface (to break the sizing?) on very smooth papers like COT 320. Anybody want to weigh in on this? I've been mostly running calibration sheets (step tablets for PDN work). I'll probably do a few prints later. My only concern is that the foam brush will abrade the surface of the paper too much with resulting loss of image detail (on the other hand - cyanotype running off willy nilly and bleeding into highlights suck).
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