I came across this book recently (ISBN:0240808541) and it has turned out to be really useful. It takes you through the process of producing high quality digital negatives (i.e. negatives created using an inkjet printer and OHP media) which are the cornerstone of alternative process photography (e.g. palladium prints, cyanotypes).Since most alternative processes require that you contact print the image, the image is ultimately limited by the size of the negative. Thus, many of the traditional photographers who use alternative processes are using large format cameras. The size of digital negatives, however, are only limited by the capability of the printer and many of today's photoprinters are capable of up to A3.
I looked into digital negatives last year when I was doing some Cyanotype printing, however, this book has provided a few clues about how I can improve the images. I used an old laser printer (HP1300) to produce a couple of digital negatives using OHP media. You will find my attempts here. The images were simply inverted in Photoshop to produce a negative and then printed. The images were OK, but weren't exactly stunning - the lack a full black and the tonal range did not match the original image.
In hindsight, the "negatives" produced on a laser printer probably lacked enough optical density to completely block out the light during the exposure to produce a pure white. These OHP negatives are not as dense as a real negative. The other issue is that I had not used a correction curve in Photoshop to map the tonal range of the digital image onto the tonal range of the cyanotype print. This is where this book really helps.
It takes you through the step-by-step process for producing a correction curve for a particular alternative process and then shows you how to use this curve to produce a high quality digital negative. While some of the technology referred to in the book is slightly out of date now, the process of producing and applying the correction curves remains the same.
It is a really useful little book, although it is a little expensive and I do wish it was in a larger format with more gallery images. The associated website (where you can download some of the digital material) could be a little more aspiring and I do think the authors missed a bit of a trick in that it could have been used as a repository for readers to upload their own correction curves for others to use.
