Although I’ve been making contact printing frames for almost 15 years now, it’s been a long time since I did any serious printing. So for my own pleasure (or frustration as is often the case), and to better understand the needs of my contact printing frame customers, I ordered up some cyanotype and gum bichromate chemistry and got down to business.
I’ve read and re-read everything I can get my hands on and there’s still much out there I haven’t found yet. My goto volumes are The Gum Bichromate Book by David Skopick, The Book of Alternative Photographic Processes by Christopher James, In Defense of Gum Bichromate a web site by Katharine Thayer, Bostick and Sullivan, Photographer’s Formulary… and the list goes on. It’s encouraging to know I’m not alone.
Cyanotype was and is again my first step into hand printing and can also serve as a base layer for other processes such as gum bichromate. The cyanotype chemistry is a simple two part recipe that’s fairly non-toxic and pretty hard to mess up. The most difficult part, I suppose, is making…
Used to be negatives were made in a camera on a sheet or roll of film. A few still are but there’s another way. Volumes of literature and many well documented systems have grown up around the making of functional photographic negatives from ink on clear plastic. And that’s particularly good news for artists who make prints by hand using 19th century methods that require full size negatives. Not only can we now use images captured on digital cameras, but we can even upscale all that old film from the archives. While producing a full size negative directly in camera has always been a challenge, many of those roadblocks have fallen to digital technology. Even a lowly 35mm film negative can be turned into a ULF (ultra large format) negative with a digital camera or scanner and an inkjet printer.
Upscaling an Image
I’m fortunate to have picked up an Olympus macro bellows outfit back in the day. Using an inexpensive adapter, it fits nicely on my Canon digital camera. I can point this rig at a backlit negative or slide and quickly turn a small image into a multi-megapixel high resolution raw file that can easily (I use the term loosely) be printed large on a sheet of Pictorico OHP film via inkjet printer. Yeah, I know I probably made that sound easier than it really is. There are a few refinements that will make your print look it’s best and require some technical magic, but nothing even close to the difficulty of creating a set of analog color separations or even a good enlarged monochrome negative.
Five Useful Editing Functions
There are too many photo editing applications to write another step-by-step how to article but here are the five essential functions a good photo editor should have. Note: Images shown below are from Photoshop CC 2019 on Windows 10 platform. Click to enlarge.
Rotate/Flip – It’s important to get the ink side of your digital negative into direct contact with the print. Even the few thousandths of an inch thickness of the film will degrade the sharpness of your print. If you don’t flip the negative image right to left (horizontally) the printed image will appear backward when the ink side is on the print.
Curves – Photosensitive emulsions have various responses to UV radiation. An image that looks fine on your monitor, when converted to a digital negative may print with too much or too little contrast. You can control this by adjusting the image curve in your photo editor. Be advised, however that some printers believe strongly that using curves is an essential step in the hand printing processes while others don’t necessarily agree. This choice is up to you. I wont go into the details here, but it’s best if your app has this function available.
Channels/BW – So let’s say you have this great slide your grandpa made in 1963. You could make a cyanotype from it by digitizing then converting the image file to black and white – a fairly simple process. The other option would be to make a set of negatives for a tri-color gum bichromate print by using the color channels for separate negatives. Either way you’ll need access to the monochrome versions of your image with the color information stripped away. The channels function gives you three (RGB) or four (CMYK) monochrome files to work with. The convert to BW function gives you one file and usually gives you some extra control of the luminance contributions of each color from the original image. But you’re still working with positive image(s). So what do you do?
Invert – This is the function that converts that positive image to it’s negative. In Photoshop it’s as easy as typing Ctrl-i. Note that some printer drivers can perform both invert and flip functions as well.
ICM Profile Support – Apply a custom printer control profile that is specific to your printer/ink and to the media you’re printing on. Most media manufacturers, including the popular Pictorico clear films provide a good selection of custom made profiles for many popular printers.
We’ll that’s enough for today. Remember, I’m no expert here. This is what I’ve discovered by researching and by trial and error (lots of error). I believe the information I’ve provided to be correct and I hope it’s helpful. I going to get back to the darkroom now and see what I can actually make instead of just talking about it. Stay tuned for more stories as I try to master the fascinating craft of hand made photographic prints.