Archive ”cyanotype”

Eric and Tzipora

Eric and Tziopra

November 7, 2013
Eric and Tzipora

The Colors of Cyan…

September 8, 2013
2-part traditional cyanotype chemistry

2-part cyanotypes …

January 29, 2013
The Widow

The Making of a Wi…

December 25, 2012
Gum over cyanotype on a half sheet of Stonehenge Rising warm white paper.
This print is a direct result of a morning of failures last week. My cyan pigment wouldn't stay on the paper - a combination of two different problems related to two variables I changed simultaneously. After three poor prints I decided I would forego the cyan for the morning and use cyanotype for the base layer to get me started.
I miscalculated the amount of cyanotype solution I needed (resulting in the large cyan area around the edges), and an hour of exposure was about a stop shy of what I wanted, but I managed to correct it with a subsequent layer of cyan gum (for which I again changed two variables, but at least it worked).
From memory, I believe this was 5 layers of gum (M/Y/M/Y/C) on top of one layer of cyanotype. I seem to be settling in on 6-7 layers per print on this paper.


April 23, 2012
This one takes some explaining; it's some of what's been eating up my time for the past few weeks.
This shot started life on HP5+ developed in Xtol. I digitally inverted and enlarged the shot and printed it on Pictorico Ultra Premium OHP before stuffing it in to my vacuum frame (yes, that shot shows me mis-printing a positive I printed first - oops).
Traditionally, Cyanotype has a "part A" (green ferric ammonium citrate) and a "part B" (Potassium Ferricyanide). Usually you mix equal parts together, put it on paper, dry it, and expose it to UV light for a few minutes (outside) to an hour (under a UV light). Results are generally high-contrast and very very blue.
This print was made with an alternative method - reportedly the same one that Sir John Hershel used, which has been generally forgotten. I stumbled across an old thread on some forum or other last week where this was mentioned in passing and decided I had to give it a try: instead of mixing parts A and B, you just coat the paper in part A and then expose it. Afterward you develop it in part B, and then wash it with water. The results are a substantially lower contrast print with excellent tonality.
After initial printing, this was a typical cyanotype blue. I soaked it in coffee for about an hour to give it this final tone. My next print was going to be bleached (in borax or ammonia) and then toned (with coffee or tea) - but I broke my UV lamp instead, so that will have to wait a few days. I'm using a backup UV lamp that's not nearly as bright and am printing 31-step wedges to see just how well this new technique works.
Of course this raised another set of questions for me: Mike Ware created a "New Cyanotype" recipe that is faster and offers a greater tonal range. (I use this too, and have to admit that it seems superior in many ways.) I have to wonder if it's possible to use Ammonium Iron(III) Oxalate mixed with Ammonium Dichromate like the traditional "part A", and then develop in Potassium Ferricyanide (same as the traditional "part B"). I think I'll have to try this out the next time I mix up a new batch!

It’s That Si…

March 28, 2011
This is a "New" Cyanotype, from Mike Ware's modernized Cyanotype formulation. The image may look familiar to long-time viewers; it's a rework of a previous image, direct-printed on to an 8.5x11 sheet of cyanotype-sensitized paper. Exposure time was around 5 minutes in direct (winter, low-sky) sunlight.

Angel in Blue

December 11, 2010
Next week, I'll be teaching a room of 4 and 5 year olds a little bit about film photography. I'll be giving them disposable cameras to shoot with, and figured I'd build a Camera Obscura to show them what's going on inside the camera (and why they can't see the picture as soon as they snap the shutter). I had been thinking about how I could load it up with some sort of film that didn't require a toxic developer, when a co-worker reminded me about "Sun Print" paper. This stuff is some form of cyanotype, reasonably insensitive to light (and therefore easy to handle), and develops in water.
So this weekend, I've been building things and testing with Jake. We built a camera obscura (using a pair of drug-store +2.00 reading glasses to make the image brighter than a pinhole camera - focal length 20") and a quick test showed that there was no way I was going to get any cyanotype reactivity in a reasonable length of time; math shows it's about an f/22 camera, with the paper guesstimated somewhere around ISO 12.
So I found the biggest (cheap) lens I had in the house with the largest area: a Barnes and Noble 4x5 reading magnifier. Focal length, about 6". This is the result of a 1-hour exposure with the subject (our house) in full sun. I developed it in water with a little vinegar, scanned it, and pulled out a little more detail in Photoshop (would have done it all in Lightroom, but Lightroom 2 doesn't have an invert feature).
List of materials:

One cardboard box (a MacBook outer shipping box, 6" deep)
A 4x5 fresnel reading magnifier (mine was B&N several years ago, appears to be discontinued)
One pack of 4x6 "Sun Art" (got mine via Einstein's Toolbox)
Gaffer's tape
Utility knife

I used the acrylic holder from the Sun Art paper to hold the film flat on the back of the box. The hard line on the right edge of the photo is gaffer's tape, holding on the acrylic. The line across the bottom is the edge of the acrylic. And the spot in the lower-left is from the hemostats that I used to pull the film and hold it while dipping.
On the opposite flat side of the box, I cut the 4x5 hole for the lens. I actually cut about a half inch shy on each side, and folded the cardboard into the interior; the lens is mounted to the flaps and can be moved in and out a little bit to aid focusing. It's neither sturdy nor precise.
I taped an envelope over the front as a shutter, and another over the film. Took it outside loaded with film and both envelopes down - opened the box, opened the shutter, composed the shot (projected on the inside envelope). Closed the shutter, removed the inside envelope, taped the box shut. Then opened the shutter and waited an hour. All of this is, of course, overkill for this "film"; the results would probably have been identical without the precautions.
The developing took a little practice to rinse the cyano-whatever off effectively. I started with a flat plate, but found that it tended to pool on the opposite side, leaving streaks as I removed the paper from the water. Vinegar also helped pull the image out a bit better (perhaps 5% solution, and white vinegar). I found that a very tall container worked better with a dip process.
Some of the previous attempts, where you can see either streaks (from improper washing) or patterns (from paper towels - don't use paper towels to dry) are here, here, and here.


January 18, 2010

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