Making a Gum Bichromate over Cyanotype Print
Day 1-3…making the negative…
My first few days are spent making and selecting negatives for printing. When making a print using this process, one of the requirements is to have a negative the same size as the final print. This can be either a digital negative or an actual film negative. I use a wooden view camera for my negatives in either 4x5, 5x7 or 8x10 format. I then scan the negative to assess its potential usability. Once I have a few negatives to choose from I can proceed to the next step; preparing the paper.
Day 4-6…preparing the paper…shrink, size, harden…
To make things easier I do the first two steps of preparing the paper in the kitchen. The paper I use is BFK Rives print making paper (although many people use watercolor paper). It holds up well with the many washings it has to go through. To prevent the paper from shrinking during the multiple layers of pigment, I first soak the paper in near boiling water, one at a time and usually try to do a batch of 12 sheets. I then dry it by hanging it vertically overnight.
The next day I size the paper with 250 bloom gelatin size to keep it from being stained by the watercolor pigment and hang to dry overnight as in the previous step.
The last step in preparation is to soak the paper in a hardener. With all the treatments done to the paper, it becomes soft and can be easily scratched so applying the hardener helps to prevent this.
Day 7…applying the cyanotype layer…
Once the light sensitive mixing and coating of the chemicals on to the paper begins, the light must remain subdued. A yellow bug light works best for most people. I begin initially by making test strips using the same procedure as the final print. I coat the paper with a dampened Japanese hake brush or sponge brush, dry with a hairdryer and expose the paper under an Ultra Violet Light Source. I then soak the print in a tray of water for a few minutes and the results can be seen almost immediately. Sometimes I’ll add a little hydrogen peroxide to the wash which makes the blue more intense. Doing this makes it easier to register the negative on the paper for the following gum/pigment/bichromate layers because you can see the image. I use push pins in the corners of the negative which then I can reuse for each layer. After the print has been developed in the water for about 20 minutes I let it hang to dry for a few hours or sometimes overnight.
Day 8…applying the pigmented layers
The three components of the emulsion are Gum Arabic, Watercolor Pigment and Potassium Dichromate. After deciding on the first layer of color, I need to weigh the watercolor pigment (in grams) and combine it with the Gum Arabic (measured in ml) at a specific ratio. This can be done in ordinary light, but when it is combined with the light sensitive potassium dichromate, the light must be subdued. I use a triple beam scale and very small scientific beakers marked in increments of 1ml. Sometimes I’ll use a syringe for measuring or an eye dropper. I then use another dampened hake brush and coat my paper, then dry with a hair dryer, expose under UV light, develop by soaking in several changes of water, then hang to dry over night or I use a hairdryer after air drying for a few hours. It must be completely dry before applying the next layer. A good print is never satisfactory with only one layer. It takes a lot of patience to make a print using this technique, but is definitely worth it.
8/20/2014 Bennington Potters, Bennington Vermont
One of the highlights of our travels to Maine is a little diner that serves a fabulous tofu scramble. The other is the Bennington Pottery seen in the image on the left, which has beautiful green pottery. But before we get to Bennington, there are a few other stops along the way.
Today is the first day of our trip to Monhegan Maine. Traveling on Rt 86 thru New York is somewhat relaxing during this balmy overcast day even with a bit of a drizzle. For a change of pace I decided to put on the “African Symphony Noir” and then BB King. A pleasant day for sure in spite of the weather. Adam is along for the ride and the Holga (plastic camera) will provide a diversion when faced with inclement weather. We'll hope that Ron's leg doesn't give him too much pain after falling over the weekend. Looks like he was beaten with a baseball bat!
In another month we will be having an exhibit of Ron’s paintings & my photographs of our trips to Maine - recollections. I look forward to the time when I can make alternative - process photos for a show like that, but that unfortunately seems to always find its way to the back burner. Then in October we will be demonstrating at the Edinboro Homecoming. I'll be doing a Bromoil demonstration & Ron will be demonstrating and selling his tin-scapes. The Leaf Festival is also this weekend at Frontier Park. Ron sold a painting yesterday for $500! OK! Great Day!
First stop.... Cuba New York Antiques which is just east of Olean, NY. For $10.00 I picked up a white baptismal dress for a prop for photography & Ron found a lamp for $5.00. Ron saw a black bear when we were back on the highway, but as usual, I missed it because my head was buried in the maps. The drizzle has increased but not yet raining.
More rain... Listening to Mozart- again - loaded Holga with Fugi Acros @ ei 64.... hoping to find that decisive moment that all Holga users are waiting for. Then, off to find the Bennington diner for Tofu Scramble. After breakfast we stopped at Bennington Potters and bought some bowls and coffee mugs. Next stop… Ashland.