CYANOTYPE ON GLASS

After using the cyanotype technique on paper, I tried another technique – cyanotype on glass.

Liquid emulsion is applied to glass and washed with water.

The task sounds simple. Is it?

Various kitchen items on a table, including a measuring cup with water, a glass of salt, a beaker with yellow powder, and more—captured by Damir Pildek in the style of an old photographic process reminiscent of cyanotype on glass.

EMULSION PREPARATION FOR CYANOTYPE ON GLASS :

Potassium Ferrocyanide 28g
Ferric Ammonium Citrate 82g
Oxalic acid 3g
Gelatine 80g
Water 600ml

The process begins by mixing 3g of oxalic acid in 600 mL of distilled water, followed by Potassium Ferrocyanide 28g, Ferric Ammonium Citrate 82g, and finally 80g of gelatine. Prepare everything in cold water. The water should be cold for gelatine because the gelatine particles will not stick to the lumps, and it will be easier to dissolve them. We must mix the solution until everything is dissolved. The next step is to heat the pan to 65 degrees Celsius with constant stirring. When the liquid becomes viscous, almost like water, we stop heating it and stirring. This liquid is now prepared to be filtered, which can be done with an ordinary coffee filter. The emulsion is now finished!

After filtration, store the finished emulsion in a dark, light-tight container. Its lifespan is around one year. You can use foil containing the films or photo paper, or if you have none of this, plain aluminium foil to wrap the jar in which the emulsion is stored. It is recommended that the emulsion “stabilize” for a day or two before use. The main difference with the ordinary cyanotype technique is its substrate, which is now glass instead of paper.
Depending on the photo format, 2mm or 3mm thick glass is used. Smoothing the edges of the glass is desirable so that we do not risk injuries when handling it.

A silver foil coffee bag sits next to a stainless steel mug with a handle, which is placed on a digital scale. The mug contains a jar with a yellow lid. The background includes parts of kitchen items.

Several clear glass sheets are stacked at an angle, partially overlapping each other, and resting on a wooden and black stand against a light-colored wall.

GLASS PREPARATION FOR CYANOTYPE ON GLASS :

The glass must be thoroughly clean of grease and dust. There are many ways to clean the surface, but careful cleaning with a coarse sponge and dishwasher detergent will be enough. After cleaning, it is crucial to rinse the glass with water thoroughly to avoid any possible residue of cleaning substances or agents. Wipe all water off the surface and dry it thoroughly. Remember that every fingerprint will leave an oily swell on the emulsion, so handle the surface carefully.

APPLYING EMULSION:

Place the jar with the emulsion in hot water (approx. 65 °C) and wait until the emulsion is entirely liquid. Prepare the glass and the spoon that you will use to scoop the hot emulsion. The emulsion is poured into the centre of the glass until it covers approximately 70% of the surface, slowly pouring from edge to edge, and the rest is poured into a separate container. Filter the emulsion residues before returning to the emulsion jar to avoid contamination with possible dust or debris from the glass. The coated glass plate is placed vertically on the blotting paper to allow the emulsion to dry. Excess emulsion accumulates at the bottom edge of the plate, and it is necessary to move the plate several times to remove the excess emulsion. Drying speed depends on the temperature and humidity in the air. Do not dry the glass with a blow dryer or over strong heat sources, as the emulsion will start to melt and will be unusable.

A tall, slender vase holds two wilted roses, set against a textured blue background with condensation and water droplets. Rendered as a cyanotype on glass by Damir Pildek, the scene evokes a moody, monochromatic blue tone.

A blue image shows a viscous liquid stream descending into a container, with bubbles along the bottom and a label reading Emulsion Melting pointing toward the liquid flow, evoking the look of a cyanotype on glass.

Impatience does not pay off. The emulsion will likely eventually melt if you dry the plate with warm air. In the upper right corner of the picture on the left, you can see how the emulsion responds to leftover particles after cleaning the plate.
In the right picture, you can see how the emulsion disappeared on the thin section and how it is melted on the girl’s forehead. Other irregularities result from insufficient cleaning of the glass

A portrait of a woman with a calm expression, rendered in blue tones and painterly textures—a modern take on an old historic process, reminiscent of a cyanotype on glass, with white splashes framing the image.

In the gallery you can see some of my works – cyanotype on glass

Here are some pictures from the lab while preparing a cyanotype on glass process.

A wooden stand holds several translucent photographic plates, some created with cyanotype on glass—a nod to an old historic process—by Damir Pildek. On the left, vintage cameras and a purple container sit on a table. The background is plain.

A laboratory workspace featuring glass plates drying upright—some prepared for cyanotype on glass by Damir Pildek—alongside a beaker with liquid, a container with an orange lid on a stirrer, and newspaper sheets atop a gray counter under a wall-mounted faucet.

A wooden stand holds several upright, transparent blue heart-shaped glass panes, each featuring cyanotype on glass by Damir Pildek, arranged in a row on a white surface.

A wooden stand displays several blue-tinted cyanotype on glass sheets by Damir Pildek arranged upright in a row, each showing faint images or patterns. The setup rests on a white surface with a blurred background.

A wooden display case with two framed, negative-tone photographs—one with long hair on the left and one wearing glasses on the right—presented side by side as a cyanotype on glass, each in a contact frame, by Damir Pildek.

A small wooden folding stool holds two glass plates with blue photographic images, created using cyanotype on glass by Damir Pildek. Light shines from the left, casting soft shadows on a neutral background.

A close-up view of a cyanotype on glass by Damir Pildek, showcasing blue architectural details created with an old photographic process, and held in place by a wooden frame with metal screws.

A person in old-fashioned clothing stands near a historic, weathered building with a sundial on its wall, illuminated by a streetlamp at night; the scene has a blue monochrome tint, reminiscent of cyanotype on glass by Damir Pildek.