cyanotype and adding dichromate
I use the cyanotype ii chemicals from alternative photography.
I read there: "The addition of dichromate extends the shelf-life of the sensitizer almost indefinitely."
If i do not add the dichromate does anybody know how long the solution will last?
6 months, maybe, perhaps a bit longer. What happens is that it becomes increasingly bluish. A bit of dichromate is a good idea, you can always lower contrast again by adding some citric acid.
I would be interested which paper you intend to use?
until now i used fabriano, arches and bergger cod 320.
(all three pages: http://www.foto-art.nl/galleries/cyanotype/total.htm)
The fabriano has more structure, i prefer a somewhat neutral look, so i prefer the bergger cod 320 at this point.
Thank you for posting the pictures. I presume the Fabriano is F. Artistico, and which paper of Arches are you using?
I ask because, as far as I can judge the image files on the screen, technically this process could be much enhanced. Please don't mind my following remarks; I like your pictures, but unless this is what you want, the dark vaues are not nearly as dark as they might, and consequently they appear somewhat flat to me. In fact, I would have taken your pictures for traditional cyanotypes (or are they?) printed on somewhat alkaline paper (F. Artistico has an alkaline base which it is advisable to neutralize before using the paper for iron salt processes), and the third, the lion face in stone, additionally washed in alkaline water.
The New Cyanotype process is very sensitive to any paper impurities, more than any other process I have tried.
Just an additional remark: I saw the infrared with the two trees printed in b+w on your wibsite, and the picture looks much richer this way, with more details in the sky, clearly visible on my screen. The Cyanotype process, also the traditional one, should enhance the tonal values rather than diminishing them.
By the way, I liked your series on death.
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i now went over to a non pre- alkaline wash with some vinegar added to it for 1 minute, after that wash for 5 minutes in alkaline water.
Or should i wash the whole 5 minutes in non-alkaline water?
The water overhere is very soft.
The photo of the tree, was removed too soon from the sun (it started to rain heavily....) before the blue/gray inversion.
I am at this point using cyanotype for 1-2 months and am always open for improvements...
"the dark vaues are not nearly as dark as they might"
Probably the density is not high enough of the negative. this could also be a point to use the dichromate..
the three cyanotypes on your website, are they executed as traditional or new cyanotypes (II)? They look to me like traditional ones printed on paper which still contained its alkaline reserve.
Traditional and New cyanotypes are quite different in execution, but both do not like an alkaline base.
For traditional: if you don't use Arches Platine or another of those rare neutral papers, bath the paper first in a 1-2 % acid bath, for about 10 minutes, or until no more bubbles emerge. You may leave the acid inside and just dry, but I prefer to wash it out in neutral water. The first developing bath should also be in acid if you prefer a somewhat longer tonal scale and darker blues. washing can then continue in neutral water, but if you wash too long, or your tab water is slightly alkaline (as is mine here), a purple tinge appears, and highlights get washed out.
I don't quite understand your remark about the dichromate: do you use it for contrast control, or immerse prints in it after development? For traditional or New cyanotypes?
As for new cyanotypes, I might be able to give support, but a cardinal problem is the right paper, so I need to know exactly which paper you intend to print on.
i use the new cyanotype ii process.
my development time is around 2-3 minutes in full sun light.
The dichromate i should have added during creation of the stuff, but i forgot this... I now bought chemicals to create it myself.
the first time i washed i had the water getting directly onto the paper surface which eventually washed out the color. I washed for an hour....
Now i prewash with the vinegar and after that 5 minutes with water (no water hitting the paper directly!
Arches Grain Fine, Cold Pressed.
In the near future i will search for a good aquarel based paper to use.
i want not to much structured paper.
The Arches paper is definitely not suitable for the process. I don't know the Bergger, but I suppose it is Arches Platine, maybe additionally sized. The problem with Arches Platine is that different batches often tend to differ also in quality, even though it is made for iron salt processes. I have made good New cyanotype prints on this paper, but I also once had a batch totaly unsuitable for printing. Recently I ordered another batch which works fine for other processes, but much to my dismay gives problems with New C.
Paper, as I stated, is a problem, and I am just trying Buxton paper, a very expensive, hand-made paper, made after specifications by Mike Ware, the inventor of the New C. process. It is painfully expensive, but i am about to order a larger quantity, because it seems to save me from so much frustration.
In any case, wash the image first for ca. one minute in 1% hydrochloric or nitric acid, and then in water. And, normal papers need to be neutralized.
I suppose on the Arches you use, the sensitizer solutution turns from yellow to green on the paper: this is a sure sign that the paper is inadequate!
you are right!
Originally Posted by Lukas Werth
for the cot 320 paper see:
They mention it is also for cyanotype.
I used this for palladium at a workshop, it's nice paper but not very cheap.