Turmeric is one of the most vibrantly colored spices you’ll ever see, and it’s a staple of Indian cuisine, but it’s capable of so much more. Curcumin, one of the plant’s primary constituents, has a long list of health advantages, and it’s been used to dye textiles for years.
Curcumin, on the other hand, is a photosensitizer, which means it reacts chemically when exposed to light. In reality, you can use it to print photos using anthotype, a 19th-century process that employs plant emulsions and sun exposure to make images on porous materials such as paper and fabric.
How to make your anthotypes at home
Stats
Preparation time: 10 minutes; cooking time: 1 to 3 hours (exposure)
The cost of the materials was less than 25 cents for each print.
Difficulty: Simple
Materials
- 1 teaspoon powdered turmeric
- 2 teaspoons of borax
- 50 milliliters of rubbing alcohol (0.2 cups)
- water (0.5 cups)
- 1 fibrous paper sheet
- A negative, or whatever you’d like to print—it may be a flower, a leaf, or something else entirely.
Tools
- There are two little containers
- Spoon
- Sponge cloth (or brush)
- Bottle for spraying
- Filter for coffee (or cheesecloth)
- Spoon for measuring
- Cups for measuring
- Photo holder
- Sun
- Towels paper
- Gloves made of rubber (optional)
Instructions
1. In a jar, combine the turmeric powder and the alcohol.
Turmeric colors almost everything it comes into contact with, so wear rubber gloves and cover your clothes with an apron or even a garbage bag. Because turmeric stains plastic containers, it’s best to choose one that’s either disposable or made of glass.
2. Strain the mixture into a new container using a coffee filter or cheesecloth.
This will help you remove the powder, allowing the colored alcohol to spread more evenly on the paper.
3. Brush the dye onto the paper in the darkest area you have and let it dry.
The bleaching process of the dye is triggered by light, which you only want to happen when you’re exposing your photograph. It doesn’t have to be completely dark—a closet, pantry, or a dimly lit kitchen area will suffice. Apply a thin layer of dye on the paper, making sure the color is as flat as possible. Wait 15 minutes for the paper to dry when you’ve finished.
Note: If you’re doing this in your closet, make sure to protect your stored items from the turmeric dye, which could stain them. If you’re drying your paper on a flat surface like a tray, it’s also a good idea to lay down a layer of paper towels first to absorb any extra dye.
A good rule of thumb is that the more fibers in your paper, the better. The best paper to use is recycled or watercolor paper, but you can use anything you have on hand, including A4 printer paper.
4. Place your print’s subject (the negative) on the paper.
You can be as creative as you want here, so pick something that will leave an imprint on the paper. It could be as simple as pressed flowers or leaves, or it could be as sophisticated as an image produced on transparency film or sketched on thin paper using archival ink. To block as much light as possible, a printed or traced negative must have thick, heavy lines.
Pro tip: You can use an actual photograph as your negative by printing the desired image in black and white on your home printer. Keep in mind that standard printer paper can block some light, thus your anthotype will likely take longer to complete.
5. When you’re happy with your composition, put it in the photo frame.
Don’t worry if you don’t have a frame in the exact size you require. Technically, only the glass is required because it serves as a weight to keep everything in place while allowing light to pass through. For example, if you have a huge frame that you can disassemble, you can use it to expose as many photographs as you can put underneath it.
6. Wait for your images to be exposed to the sun.
Place your images on a flat surface that is exposed to the sun. The length of time you leave them out will be determined by the time of day, the weather, and the amount of contrast you want in your shot. Consider extending the exposure time if the weather is cloudy.
It’s also crucial to consider how well your negative inhibit light. Physical barriers, such as green leaves, will produce a clear, dark imprint, but a weakly pigmented picture will allow light to pass through, resulting in faint or non-existent lines. You can play about with different exposure durations and angles regarding the sun, but don’t move your negative because it will be difficult to reposition it in the same location, resulting in a hazy image.
When compared to a curcumin-dyed piece of paper before exposure, this is a fully exposed anthotype. Sandra Gutierrez Gutierrez Gutierrez Gutierrez Gutierrez Gutierrez
Pro tip: A excellent way to tell if your image is ready is to look at the color of the paper. The exposed surface should change color from a bright yellow to a mild, lemony shade.
7. Prepare a solution of borax.
Simply combine the borax and water in a spray bottle.
Use warm water to completely dissolve the borax.
8. When the exposure period is finished, move your photographs out of the sun.
You’ll notice that your image’s backdrop color is significantly lighter than it was previously. When you remove the negative, you’ll find a much darker color imprint it left behind.
Note: If you like the way this looks, you can stop here and display your new print. The issue is that the bleaching process will continue unabated, and your image will fade with time.
9. Apply a thin layer of the borax solution to your image.
Place your print on a paper towel and let it dry. Spray a thin layer of borax solution over the print after thoroughly shaking it. Within 10 minutes, the darker yellow lines will become various colors of orange, red, and brown.
Note: If you spray more borax solution, the backdrop will react as well, leaving you with a large dark stain.
10. Allow time for your image to dry.
Anthotype, like any other creative process, isn’t a flawless science, and you’ll probably have to try until you obtain exactly what you want. Experiment with different dye concentrations and negatives. See what an extra hour of exposure does for your photograph, or if the location you pick to expose your photos has any bearing on the final results. It’s all part of the excitement.
The origins of anthotype
Sunlight is both a wave and an energy source in the form of photons. Curcumin, the molecule that gives turmeric its color, may absorb these photons because it has photosensitizing properties.
However, absorbing energy isn’t free, because when curcumin molecules light up, their electrons reorganize, resulting in highly energetic forms of oxygen. Because the turmeric color fades away, these new molecules react with the paper and cause a bleaching effect.
When you spray the borax solution over the anthotype, it reacts with the curcumin, which is more abundant in the portions of the anthotype that were not exposed to the sun—the lines that form the image.
This reaction produces boron-based compounds with a dual effect. To begin with, they inhibit future dye bleaching, ensuring that your image does not fade with time and light exposure. Second, they improve the image’s definition by giving the areas under the negative a darker tone.
