[Alt-photo] cyanotype paper
bobkiss at caribsurf.com
Sun Dec 3 17:10:53 UTC 2017
Recently, I dug back into my 1970s edition of Kosar and it was even mentioned there that one could actually mix some fumed silica into the coating solution and that it would increase Dmax. If you are interested I could try to find the page # and edition # of my oooooooooooooooooooooold text book.
From: "alt-photo-process-list at lists.altphotolist.org" <alt-photo-process-list at lists.altphotolist.org>
To: "Richard Sullivan" <sullivan8486 at gmail.com>
Cc: "alt-photo-process-list at lists.altphotolist.org" <alt-photo-process-list at lists.altphotolist.org>
Sent: Sunday, December 3, 2017 11:02:37 AM
Subject: Re: [Alt-photo] cyanotype paper
I have seen that silver nitrate formula often: Wall, Brown’s Ferric and Heliographic Processes, Hoppé, Photographic News... One calls it “Imitation Platinotype.” I have lots of silver nitrate lying around from salted paper and planned on trying it one of these days.
Silica seems to be a holy grail with pt/pd. Am I right in that assessment? I have never used it. I read on your website that you suggest it deals with the buffering in the paper, or does it attract humidity so the paper remains moist or what? What exactly is its role in pt/pd?
I tried to find the pH of fumed silica and it seems it might be on the acid side. If so, that would be good for cyanotype and its problem with alkaline papers.
Just thinking aloud here, trying to see if its pH or its humidity effects are what are improving the cyanotype process for you.
Ware says he has not found humidity to be a factor in cyanotype as in other processes (p. 181 Cyanomicon II) and so far that has been my case, too, which, of course, makes it quite user-friendly for a Montana climate.
But the ubiquitous calcium carbonate buffering is such a PIMA with cyanotype and if silica did, in fact, improve that, it’d be a great ingredient to have on hand.
On Dec 2, 2017, at 10:01 AM, Richard Sullivan <sullivan8486 at gmail.com> wrote:
A quick add-on
When coating with fumed silica the silica seems to take over. When I was first testing it with PD/PT, I asked Dana what was in his knowledge the worst paper to use for PD/PT. He said without a doubt Lannaquerell. Gordon mark and I grabbed a few sheets and the results were stunning, nice prints on the coated side and crap on the uncoated silica side.
On Sat, Dec 2, 2017 at 9:56 AM, Richard Sullivan <sullivan8486 at gmail.com <mailto:sullivan8486 at gmail.com>> wrote:
>From an unknown source and from my archives. I found thus about 40 years ago. Never tried it.
"> To Color Blue Prints Black.
— To get the desired color, bathe the
print in distilled water and immerse in a 2 per cent, nitrate of silver
solution. After bleaching of the picture, wash again in distilled water,
dry and expose to ammonia vapors. A short exposure and subsequent
development with oxalate of iron will produce a good black silver
Paper be damned. A few years ago my assistant Madelyn Willis (pic below) and I were exploring fumed silica and cyans.
Below on the left (her right) is a fumed silica coated print, the left one is non-silica coated.
We used the same mix for both and did our best to coate, expose, etc the same for both.
The results were even more stunning when we used something we called
SuperBlue from a 1950's formula for commercial BP paper.
As for details check Advanced patent search and search for "Cyanotype blueprint Jahoda."
Of further interest Patent No.:
Also note that guanidine ferric oxalate was the iron salt of choice in the latter period of the blueprint.
How to make:
(Originally derived from guano off islands near Chile. Known around here as batsh*t ferric oxalate.)
I have some guanidine carbonate here.
On Sat, Dec 2, 2017 at 9:12 AM, Christina Z. Anderson via Alt-photo-process-list <alt-photo-process-list at lists.altphotolist.org <mailto:alt-photo-process-list at lists.altphotolist.org>> wrote:
You started me on this trend a long time ago when you posted the topic of bleeding and information you had found in patents on the list. Since then I have changed the typical 20%/8% you see quoted in books, including my own, to a minimum of 20%/10% to make sure the ratio is no greater than 2:1 (I know you had discussed molar amounts and yours was 18/8). The sky didn’t fall in.
Then through my research into formulas I found that they were so completely all over the board that I started testing a 4:1 FAC:PF to 1:4 FAC:PF and was surprised how little difference it makes. You still get a print. However, the speed is slower. But the color is more turquoise and less navy (goes more green than red) and it is much smoother.
When I began testing papers for my upcoming cyanotype intensive class spring semester, since I started with the 10/10 I just kept on, to keep apples to apples. When I narrow down to a few select papers I’ll go back to the 20/10 to see if the speed increase is worth it over the smoothness and color I prefer.
When I was using the 20/8 I was also often using 2A:1B or 40:8! No wonder I had bleeding and it was you, Alberto, who saved the day!
PS Another paper I have had great luck with is Clearprint 1020H. 100% cotton. It amounts to about 20¢ for a 9x12! This and Canson U-Sketch/Crob Art have to be about the cheapest (14¢ a 9x12) but the Clearprint specifies cotton and archival and the Canson does not say what the paper is made of. I do tape the paper down when coating. I much prefer it to the lighter weight 100H Clearprint but the lighter weight is conveniently often sold in small pads.
https://www.amazon.com/CLEARPRINT-VELLUM-1000HP-18X24-PAD/dp/B000KNL9PM/ref=sr_1_4?ie=UTF8&qid=1512230214&sr=8-4&keywords=clearprint+1020 <https://www.amazon.com/CLEARPRINT-VELLUM-1000HP-18X24-PAD/dp/B000KNL9PM/ref=sr_1_4?ie=UTF8&qid=1512230214&sr=8-4&keywords=clearprint+1020> <https://www.amazon.com/CLEARPRINT-VELLUM-1000HP-18X24-PAD/dp/B000KNL9PM/ref=sr_1_4?ie=UTF8&qid=1512230214&sr=8-4&keywords=clearprint+1020 <https://www.amazon.com/CLEARPRINT-VELLUM-1000HP-18X24-PAD/dp/B000KNL9PM/ref=sr_1_4?ie=UTF8&qid=1512230214&sr=8-4&keywords=clearprint+1020>>
http://www.michaels.com/canson-universal-sketch-pad/M10121123.html <http://www.michaels.com/canson-universal-sketch-pad/M10121123.html> <http://www.michaels.com/canson-universal-sketch-pad/M10121123.html <http://www.michaels.com/canson-universal-sketch-pad/M10121123.html>>
> On Dec 2, 2017, at 12:33 AM, Alberto Novo <alt.list at albertonovo.it <mailto:alt.list at albertonovo.it>> wrote:
>> With vinegar and citric it leans turquoise. With sulfamic it leans purple. Caveat: I am using classic cyanotype at only a 10% ferric ammonium citrate/10% potassium ferricyanide so YRMV, but UVBL exposures are 12-19 minutes with acid development.
> Hi Chris,
> I see that you have switched to a greater amount of ferricyanide, like we discussed time ago.
> Hence, there are some benefits, isnt'it?
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