Re: cyanotype question
Awesome, Chris! Thank you so much for the hard work and helpful illustrations. One question - in my dilution tests, I just used 1A + 1B + xW. Why did you decide to use B = (A+xW)? Best wishes Henry On 7/12/08 18:03, "Christina Z. Anderson" <zphoto@montana.net> wrote: > LOL Charles, > Sam Wang and I have been laboriously doing test strips this weekend, testing > cyanotype stuff back and forth (when I really should be reading and grading > 30 papers). I just got my 3 new 4x5 step wedges (31 step) from Stouffers so > I can do three tests at a time which is really fun. > > I can blame Henry Rattle for this spate of experiments, or whoever it was > who asked the original question of getting a paler blue for a tricolor gum > underlayer. And then Sam who began to test it this weekend. > > Caveat: Sam is the cyanotype guy to be answering your question--he has done > a ton of it and I really only use cyanotype in conjunction with either gum > or palladium, the latter which I absolutely love. > > But here is what I've been mulling over: I went to my Mike Ware Cyanotype > book which of course, has all KINDS of info in it so I don't know why I > would have to reinvent the wheel. I do think the book is a must-have for > those who do cyanotype all the time. Every time I read it I find new > information again. > > He has a very interesting chapter on the different formulae in existence > since cyanotype's beginning. And what surprised me was that Herschel > originally started out with JUST pot ferri!! It was quite slow so the > practice of adding FAC began. > > So then I thought, what happens if I increase the pot ferri proportion etc.? > And water as well? > > The formulae historically range from 2%A20%B to 20%A2%B, btw. Thus why cyano > is such a forgiving process. I think you could just dump a teaspoon of each > in a cup of water and still get a good print! > > Sam and I both seem to agree that the more B the slower. > > My conclusions from this weekend are that I will, from now on, dilute A way > down when using it for tricolor gum. BUT it could be this way in MT just > because the water enables the solution to better hydrate and sink into the > paper surface, so maybe it does not have the same good outcome in a humid > environment? And I think you live in humidity? > > Anyway, here are my tests on Platine and FAEW: > > http://christinaanderson.visualserver.com/Text_page.cfm?pID=2076 > > I'm a bit hesitant to draw immediate conclusions and give you my opinion on > your question, below, but what I am finding is that the smoothest coats, and > the palest blue perfect for tricolor, come with extreme dilution of the mix, > which both Henry and Sam agree upon (dilution of 7x!). So my GUESS to your > question is that the more you add of the FAC the less smooth it may become. > You can see that the graininess and the bleeding occur on the increased A > test wedges. All of my step wedges without added water are grainier than the > ones with added water on both papers. BUT that is at 66 degrees and 23% > humidity in Montana which may be skewing these tests, so if you find out > anything could you post? > Chris > > > __________________ > > Christina Z. Anderson > http://christinaZanderson.com/ > __________________ > ----- Original Message ----- > From: "Charles Ryberg" <cryberg@comcast.net> > To: <alt-photo-process-l@usask.ca> > Sent: Sunday, December 07, 2008 10:31 AM > Subject: cyanotype question > > >> Folks: While struggling with the hassles of getting a smooth second coat >> on cyanotype it occurred to me that I could just double the strength of >> the solution--40 grams instead of 20 FAC in 100 ml water. Has anyone ever >> tried this? >> Thanks Charles Portland Oregon >> > >
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