Getting Started
Everyone's favorite analogy to emulsion making is cooking. It's a natural. Emulsion making is cooking. Think about basic bread for a minute. Wheat, water, salt, and yeast. Nothing could be simpler in concept, but a lot is going on, right down to the Krebs cycle of the yeast. The fermentation process makes carbon dioxide. If the gluten is properly developed, the gas will push up the loaf so that you get bread instead of a brick. The salt is in there for both taste and fermentation control. If you decide to substitute rye flour for the wheat, you know you'll get a different kind of loaf. You might know to make subtle changes to the rest of recipe.
The point to all this is that I suspect few people would think they have to draw the Krebs cycle or a gluten molecule, or know that salt is sodium chloride to make a simple loaf of bread. Understanding all that stuff is interesting, even great fun, and might help your cooking skills advance to higher levels, but when it gets right down to it, the scientific details are entirely optional for making bread. You just need a good recipe and a tummy hungry for homemade bread.
Just as important to our approach to ingredients is our approach to equipment. Imagine for a moment that you've never made bread but would like to try your hand at a loaf. I hope you would look for a recipe that calls for as little equipment as possible. You can make do with a big bowl and wooden spoon, a surface to knead the dough, and an oven. If you decide you really like homemade bread, you might consider buying a good mixer. I doubt you would believe that you had to buy an automatic bread making machine in order to get a loaf to eat.
Humor Break: From one of my favorite humor books, How to Talk Minnesotan—a vistor's guide, by Howard Mohr, Penguin Books, 1987. "...the Minnesota taco, pronounced tack-oh... Many cooks substitute pickled herring for the hamburger and use cream of mushroom soup instead of Cheese Whiz as a topping. Lettuce is optional. Buttered and folded white bread can be substituted for the tortillas..."
The point of the joke: Stretching the cooking analogy just an inch further—we are learning a cuisine. it's only smart to follow the recipes very carefully. As we get closer to "high school" level, we'll start looking at recipe modification, but not yet. True fact: I've had people tell me they've essentially substituted pickled herring for hamburger and can't understand why they didn't get a nice emulsion. In addition to the potential pitfalls of random substitution, the recipes have been designed to be used together—a cuisine, if you will.
Ingredients/Chemistry
The first recipe, a chloride paper emulsion, calls for
- Distilled water
- Photographic gelatin (I buy mine from Photographers' Formulary)
- Potassium chloride
- Silver nitrate
- Photoflo 200
- Everclear, or unflavored vodka
To give you an idea of how much to order, per recipe we will use 3 g of potassium chloride, 5 g silver nitrate, and 25 g gelatin. Most recipes follow those general quantities. Since it is cheaper per gram to buy larger quantities, and shipping costs can almost equal the price of many ingredients, I suggest you buy enough for at least 10 recipes. After you get your feet wet, and decide you love doing this (and you will!) you can amp up your quantities.
Also, you will need to lay in processing chemistry. Kodak HC110 is an excellent all-purpose commercial developer. BW-65 liquid paper developer from Photographers' Formulary can give beautiful results. Handmade developers work as well, or, in some cases, better than commercial. The Light Farm book has recipes and instructions. D-23 (home-mixed from metol and sodium sulfite) in perfect for plates and film. The recipe for D-23, along with variations, is in lesson #13.
Paper
The paper recipes in the first half of the workshops are designed to be wet-coated on lightweight watercolor paper. I highly recommend Arches watercolor paper, HP (smooth), 90 lb, and/or Fabriano Artistico Traditional White, HP, 90 lb. The Arches is a clean white, and the Fab Art is a warm white. Both papers are available from Dick Blick supplies in 22"x 30" sheets.
For Paper Coating
- Coating surfaces: sheets of thick glass (expanded information coming in the next installment.)
- "Puddle Pusher" glass coating rods (at least two). The 9-inch size is the one I use most often.
- Tape and wall putty (you will be prepping the rods like the first two pictures on this page).
- Several sheets of Duralar, acetate, mylar, or Yupo.
- A squeegee. I use two different styles with equal success—one made specifically for photography and one made window cleaning and shower drying.
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