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earlj
03-31-2006, 10:46 PM
This time I tried coating the solution twice, as advised by Carl. This seems to have done the trick. This image is from two years ago - the Mississippi River from Hidden Falls Park in St. Paul on a misty, rainy morning in May. The negative was developed in PMK pyro, and the subtleties of the scene are mostly visible in this blueprint. The paper is Fabriano Artistico. Classic cyanotype formula, brush coated twice. Exposed with the spiral BLB bulb for 2 hours, 30 minutes.

Attached files http://f295.f295.org/uploads/rivercyano_606.jpg (http://f295.f295.org/uploads/rivercyano_606.jpg)

stormy
03-31-2006, 10:50 PM
Wow - very cool image, Earl.

The roots make me think of giant octupi.

Marv
03-31-2006, 11:04 PM
Yep, that's it, nailed that one!

I probaly have taken 60 or 70% of my images along the Mississipi. It's an ever changing subject. You know you have 4 shots a year in any location, just follow the seasons.

staft
03-31-2006, 11:20 PM
i never saw this image before, so i am happy to get the chance. spectacular. and to date i think my favorite cyanotype, because there is a perfect, inevitable suitability between the image and medium. you did nail this one.

Andrew
04-01-2006, 12:06 AM
very very cool, earl.
good one.

gneissgirl
04-01-2006, 12:42 AM
By George, I think he's got it!
simply perfect, earl. I love the smoothness and the softness, but the details are there, too.

Carl Radford
04-01-2006, 07:33 AM
Looks pretty good to me Earl. It looks as though the light source can be seen in the print though - the spirals or bands of yellow - this is either the light source is too close to the paper and causing hot spots or that the image isn't being washed until all the yellow has been cleared from the image. That said, a lovely image!

earlj
04-01-2006, 08:18 AM
Looks pretty good to me Earl. It looks as though the light source can be seen in the print though - the spirals or bands of yellow - this is either the light source is too close to the paper and causing hot spots or that the image isn't being washed until all the yellow has been cleared from the image. That said, a lovely image!

Could be some of each, Carl. I will try printing the same image in the sun with the same coating technique next time I see the sun. I take it that it is not possible to wash the print too long. With the double coating, the yellow unexposed areas take a long time to clear. I soaked the print in two trays of distilled water before I started the running water wash. Our water is slightly alkaline - does this make it more difficult to clear a cyanotype?

staft
04-01-2006, 08:48 AM
i had to tilt my screen to see what you guys were talking about, but sure enough- yellow. now i get to gush all over again when we see an even better repost!

Carl Radford
04-01-2006, 11:18 AM
Not sure where the pre-soak in distilled water comes from - not heard that one? I go straight to washing the print and continue to was until the water is running clear - this can be checked by picking the print up by a corner and watching to see if the drops coming off the edge of the print are clear of colour. I believe you can over wash prints at the expense of the highlight detail so care does not to be taken. Currently in the darkroom doing some straight printing but will try and get round to more pninhole and some cyanotypes asap.

How about a min cyanotype print exchange?

earlj
04-01-2006, 11:12 PM
I took the print posted above and toned it. I used two solutions - one teaspoon tannic acid in a liter of water, and two teaspoons sodium carbonate (Arm and Hammer Washing Soda) in a liter of water. I moved the print back and forth between them with water rinses in between and this is the result. It looks better in the flesh than it does on the scan.

Attached files http://f295.f295.org/uploads/rivercyanotoned_655.jpg (http://f295.f295.org/uploads/rivercyanotoned_655.jpg)

Carl Radford
04-02-2006, 06:24 AM
That looks to have worked nicely Earl!

buggy
04-02-2006, 01:49 PM
Wonderful image.

I'm not familiar with cyanotypes and had a couple of questions.

1. What is the chemical process taking place in the toning. i.e. what is replacing what?

2. I wonder why the exposure was 2 1/2 hours? I wonder how it would print at a lower exposure.

3. Sorry for #3, but what is the purpose of the baking soda in the toning process?

I think these should be behind glass! Great work.

ImageMaker
04-02-2006, 02:23 PM
Buggy, tea toning cyanotypes has a non-simple chemistry, but to oversimplify a bit, alkali of any kind acts as a bleach, converting the Prussian blue to an uncolored chemical; tannic acid reacts with either Prussian blue (forming a warm-black substance likely mostly composed of ferric tannate) or much more rapidly with the colorless products of alkali bleaching.

I've toned cyanotypes in tea without bleaching -- they eventually get to a point of having light tan paper and almost neutral black shadows. With sodium carbonate or bicarbonate as a bleach, the end result is usually warmer in tone, probably a mixture of ferric/ferrous oxide hydrate (aka red rust) derived from ferric carbonate, and ferric tannate. Switching back and forth, as Earl has done, allows controlling the toning, more or less, by controlling how long the print is in one solution or the other.

The long exposure was most likely because the low-wattage spiral fluorescent doesn't give off enough UV to print faster -- that's an exposure that could probably be accomplished in anywhere from ten to thirty minutes in summer sun.

BTW, Earl, if your tap water is alkaline, it can encourage bleaching of the print while developing; that's why so many sources recommend doing the first rinse or two in trays with acidified water -- to ensure it's not alkaline.

earlj
04-02-2006, 03:28 PM
I've toned cyanotypes in tea without bleaching -- they eventually get to a point of having light tan paper and almost neutral black shadows. With sodium carbonate or bicarbonate as a bleach, the end result is usually warmer in tone, probably a mixture of ferric/ferrous oxide hydrate (aka red rust) derived from ferric carbonate, and ferric tannate. Switching back and forth, as Earl has done, allows controlling the toning, more or less, by controlling how long the print is in one solution or the other.


I like the tannic acid better than tea - the tannic acid/sodium carbonate combination does not stain the paper as much as the teas that I have used. This method is also pretty quick, and would allow for some split toning - you could leave the darkest areas blue and tone the lighter areas brown.

I have tried a dash of Nitric acid in my first wash, and I have tried a dash of citric acid in the first wash. The nitric makes the water much bluer, but it also seems to clear the yellow faster. I want to come up with a process that works reliably, but it is hard to know when my actions have their intended consequence. I am starting to know what a properly exposed image looks like. Now I need to find a paper and coating method that works consistently for me. I hope that I can do the final long wash in tap water, as it gets expensive to use distilled water for everything, even at .65 per gallon.

ImageMaker
04-02-2006, 10:42 PM
I've never considered using distilled for more than the first, acidified wash for mine -- at 97 cents a gallon, my cyanotypes would start to cost like van Dyke prints! Fortunately, the water here isn't very alkaline (it is, a little, but the acid first wash seems to prevent too much bleaching). Hopefully I'll get the same speed increase with cyanotype rex under the BLB as I get in sun, though, because otherwise I'll have to get an appliance timer and leave these things overnight... :P

buggy
04-02-2006, 11:01 PM
Do cyanotypes require that much more exposure, then say VDB for example? I am hearing times like 2 1/2 hours or possibly overnight. I don't think I have ever gone more then an hour with VDB using a 13 watt spiral BLB. Approx. 3 inches above the print.

Earl, how close are you placing the bulb to the print?

I'm just curious, but whatever you have been doing keep doing it. These 2 images have that something special that we all strive for.

earlj
04-02-2006, 11:18 PM
buggy - I have found that a lot depends on the negative. This particular negative was developed with alt process in mind, and was developed in PMK Pyro. It is pretty dense - it does not print as well as a silver gelatin print as it does with cyanotype. I have my lamp set about 4 inches above the contact frame. My lamp does not have a very good reflector - it is one of those articulating arm desk lamps that clamps on the edge of the table. I am sure that I will get a much shorter exposure when the sun comes out again. I am thinking that my wimpy single bulb spiral BLB setup is not going to keep me happy for much longer. I need one of the big mercury vapor exposure lamp/vacuum frame units with a built in integrator used by the screen printing firms that I worked for in a past life.

Carl Radford mentioned to me in another thread that the negative is everything in cyanotype, and I am beginning to understand that he is correct. The separation of highlight tones in the cyanotype comes from sufficient development in the negative, and this density can require time to expose . . .

ImageMaker
04-03-2006, 10:35 AM
Cyanotype is usually considered the slowest of the common alt processes, though cyanotype rex is actually at least a couple, probably 3-4 stops faster than traditional cyanotype, possibly in part due to using a wider portion of the spectrum. I used to routinely run 20-30 minute exposures in late-day sunshine with traditional cyano, but with rex I can get a good exposure in about five minutes with slightly hazy, midday, but late winter sunlight. A VDB ought to be a little faster than that -- so, by extrapolation, Earl's spiral setup might give a rex print in anywhere from 10-30 minutes, and VDB in under 20. My reflector is better than Earl's (a 9" aluminum cone, assembly clamps to a shelf etc. -- lamp, without bulb, was $7 at Lowe's home improvement store), so my times would likely be better than his anyway. Hopefully I'll get a chance to give it a try sometime soon; I've got some recent negatives that I think would look really nice on cyanotype with a light tea toning.

nicolai_g
04-03-2006, 06:18 PM
OMFG, that is a really stunning image. It looks like a languid Ed Wood-style swamp beast preening itself while high on opium. Wow.

staft
04-03-2006, 09:49 PM
OMFG, that is a really stunning image. It looks like a languid Ed Wood-style swamp beast preening itself while high on opium. Wow.

well-put, nicolai. but add to that the fevered dreams walt whitman had on the first night he spent travelling down the mississippi. massive pleistocene ganglia.

i still like the cyan/indigo best, although the tea lets me see the ancient-ness built in to this image. still awestruck.