Most of the thinking work in creating a cyanotype lies in making a digital negative from an existing image. This… is not easy. Once you get past all the testing to determine your max blue which tells you the length of exposure time, to figure out what the proper curve is to deliver a correctly exposed negative, you then have to take each image and create the digital negative.
The first step is to bring the full color image at size into Photoshop. The second step is to desaturate the color image, and add a layer with your step wedge. The purpose here is so that you can compare your step wedge to your image, checking for a full range from white to black. This is more complicated than it sounds because cyanotype is a low contrast print. So how much is too much contrast? How much is too little? Judgment calls all! So much depends on what you want the image to look like – how dark or how light.
The third step is to add an inversion layer. It’s negative, so it has to be inverted. This is the second point where you examine your image, comparing it to the step wedge. Is it still good? Do you still have the tonal range you want?
The final step is to add your curve. As soon as you add the curve the image changes completely. It has been hard for me to trust the curve. The image looks so wrong! But this is what it takes to work for the proper cyanotype exposure.
The last thing is testing. Because even though you have worked to make the best guess you can make, that’s no guarantee it will be right. Removing the test print, and watching it change as you wash the paper is both magical and nerve-wracking. Will it work? Most times, the first image fails. It will be too, dark, or too bright. The image will need minute adjustments because, I have learned, cyanotype is very sensitive to the smallest change in tones. It takes me about two tests to get a perfect image. So every image is hours of time. Hours to make the negative. Print time, and then hours, and sometimes days, to get a perfect print.
But the results are worth it. Nothing compares to these luminescent blues, the way they glow in the light. With the right subject, and not every image is good for cyanotype – most are not, the image is like something from another, better world.