The art of photography began to be influenced by the art of painting in a process beginning in the 19th century. At that time the photographic artists produced photographic pictures in terms of both subject and technical aspects in the photographs they produced. The artists who developed their techniques often chose not to share them with anyone. Nowadays, the processes and formulas related to these techniques are returned to the world of photography from the notes in the patents and family archives. This type of photography can use aging techniques for an artistic image or colors can be different and details can be destroyed.
Different printing techniques to produce images such as images;
There are various ways to get different and picture-like images with pictures and color shifts. These; soft focusing, special filters and lens coating, dark manipulation and gum-bichromate, van dyke, cyanotype, carbon, photogravure, platinum, multiple print, mixed printing techniques are used to reveal personal artistic expression. In the past, these printing techniques were used more often, of course.
Vandyke vandyke these techniques because of the “sepia-brown” tone because of the paint Van Dyke used in his paintings was likened to the color and therefore has received this name. The mixture of this method is prepared with silver nitrate, feramonium citrate and tartaric acid compound and the exposure is carried out with sunlight. For this reason, the name may also be sun printing.
One of the alternative printing techniques is Cyanotype, which is used in replica production in the field of engineering. The drawings used in the technical drawing are also from this technique. This technique gives the picture cyan blue tones and looks very nice. Now let’s explain this method in depth.
Cyanotype Printing Technique
In some sources, this method also includes Blueprint, Sun print, Ferroprussiate prints and Iron print.
Cyanotype is an iron based printing technique and has been found later than with silver salts. This method is one of the cheapest methods because you create the image with the help of iron powders. Due to the fact that it is so cheap, as mentioned above, it has been used in many different areas.
This printing technique was first discovered by British scientist and astronomer Sir John FW Herschel in 1842 and published a book about it. This technique is very durable. Herschel’s pressures are still preserved at the University of Texas.
It was started by Anna Atkins. The botanist Anna Atkins published a book in 1843 with the cyanotype application, in which seaweeds were illustrated and hand-crafted. According to Atkins, moss images captured by this photographic technique are more accurate, precise and clearer than the draft drawings. Anna Atkins later published a number of books. Then he started to produce papers specially prepared for this application.
This method was first used in architecture and by engineers to reproduce plans and technical drawings. It was cheap and easy to do. Some American companies were selling ready-made cyanotype papers from the 1870s to the 1930s.
In fact, this method is not much preferred in photographic prints because of the lack of color tone. For another reason, it is said that the blue color is not suitable for some photo subjects. The best part is that you can use this technique not only in films but also in different areas like fabric paper.
This method is called mayan Blue Print yer because of the blue (cyan: dark blue) color, or yer Blue Cyanotype yer in places where the light areas are blue, and the places that do not receive white are called eng Negative Cyanotype Bu. The British chemist Dr. Michael Ware obtained darker blues in 1987 by changing some chemicals in the Cyanotype method (using ferric ammonium oxalate instead of ferric ammonium citrate). This method is called “New Cyanotype”.
Potassium ferricyanide (red crystals are dangerous to be swallowed or inhaled.)
Ferric ammonium citrate (Brown and green ones. Green ones are more sensitive to light.)
Wooden handle brush, brown bottles (since these chemicals are very sensitive to light, their solutions should be stored in brown bottles.)
Light source: Low level tungsten light.
Negative: The most appropriate negatives are those with a density range of 0.9 to 1.4. The negatives used by the printers are used in the film.
Paper selection: Although all kinds of paper can be used in this method, moisture resistant papers should be preferred. Arches platinum (180 g) is a suitable paper.
Iron salts are used in the Cyanotype method. In this method, Fe3 + (iron III) ions are transformed into Fe2 + (iron II) by light effect and Fe2 + ions are formed by turnbull blue with potassium ferricyanide. Turnbull blue is a water-insoluble compound, so it remains on paper to form the image.
Preparation of Sensitizer Mixture
For the sensitizer mixture, there are different recipes that contain the same ingredients in different proportions.
4 g potassium ferricyanide
50 mL Destile water
10 g Ferric ammonium citrate
50 mL Destile water
These prepared solutions are stored separately in brown bottles.
1. Sensitization should be done under very low tungsten light and the containers used should be very clean.
2. Take equal volume of these two solutions and mix. With the help of a sponge brush, this mixture is applied to the paper in two directions, horizontal and vertical. Handles of brushes should be made of metal. If it is metal, it can be closed with the help of a nail polish.
3. This paper is left to dry horizontally. It can be dried with a hair dryer, but there is a risk of ions getting in the air.
4. The dried paper should be yellow-green. The bluish image shows that the process is negative.
1. Remove the paper that has dried well and place it on the contact frame by placing an enlarged negative on it. Or they may be exposed between two thick glass, without shifting, or in daylight at the UV light source. It is a good practice to pre-print. Optimal exposure time is found in trials. In daylight may last 5 to 10 minutes.
2. Light areas immediately change. Olive turns green, dark places become gray blue.
3. Load the exposed print in an empty cuvette and add water slowly. The temperature of the water should be between 180C and 240C. Chemicals in unsealed areas will flow and will remain white.
4. Water is poured and washed 4-5 more times.
5. Let the print dry in a clean place. As it dries, colors become darker.
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