How a Photographic Film is Developed

How a Photographic Film is Developed

You surely remember the cameras from the 80s that used to actually have a film, but do you know how this film is developed? We, for our part, have always been wondering how this is achieved and have finally received the chance to find out more about the techniques of developing a photographic film. Now we will take you on a behind-the-scenes tour of the entire process.

There are several development processes that can be used to develop the photographic film and we have chosen to explain the developing tank. Most of these methods only differ in the containers that are used for carrying the chemicals. They use, however, more or less the same chemicals in the actual process. The developing tank is more convenient since it allows photographic films to be developed in a daylight environment instead of a darkroom.

To begin the process of converting the latent image into a visible picture, the film needs to be loaded onto a film reel. This, however, has to be done in a completely dark environment since any light contact could result into badly developed pictures. Once the reel is loaded, it is put inside the developing tank. Then, the lid is screwed onto the tank which allows to continue the process in the daylight. In order to dissolve the outer layer of the film, the film needs to soak in cold water.

The outer layer is simply a very thin skin of gelatin  which is sensitive to water and protects the film from any scratches during the handling. After the protective layer is dissolved in water, the film is exposed to the developer solution. The solution’s primary function is to make the latent picture visible. The developer solution is comprised of a combination of chemicals, consisting of alkali and metol or hydroquinone mixed with water. One chemical within the developer solution, namely metol, reduces the sub-micron sized grains of silver halide crystals in the emulsion to black metallic silver. The developer solution has to be diluted with water according to the measurements. Once the developer is poured carefully into the tank and the push-cap is placed on top of it, the whole tank needs to be slowly flipped a few times.

After this, the developer has to be poured out completely for the next step.  The next crucial step in the developing process is the stop bath. This bath consists of a glacial acetic acid, usually around one to two percent, or water. The purpose of the stop bath is to simply halt the development of the film. There are two ways for achieving this. One way is by rinsing out the solution with water. However, during the rinsing the developing process continues at a low level for an uncontrolled period of time. If an immediate stop of the development is desired, the stop bath consisting of a glacial acetic acid is used.

This bath neutralizes any excessive development of the silver crystals when alkalis and acids are mixed together. The neutralization of the alkalinity of basic developers can help to preserve the strength of the fixer. The function of the stop bath is highly important since an overdevelopment of the silver crystals results in an image that is virtually impossible to discern. Pouring the stop bath into the tank needs to be done exactly the same way as with the developer solution.

A developing process, however, cannot be finalized without the fixer. It is a chemical mix and often also called hypo, which is the abbreviation of “hyposulphite”. In most cases, the unexposed silver halide remains on the photographic film and thus becomes sensitive to further action by light. Therefore the fixer is very important as it stabilizes the image and makes it light-resistant by dissolving the remaining silver halide salts. After the unexposed silver crystals are removed, the fixer then hardens the remaining crystals in the emulsion. This is the process that enables to preserve the photographic image over time.

Once the film has been developed, the process needs to be completed with two steps. Firstly, the film needs to be carefully rinsed with water in order to remove all the chemicals used in the steps before. If any chemicals remain, a deterioration of the image could be caused. Lastly, the film is dried in a dust-free environment, cut and placed into protective sleeves and finally ready for viewing.

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How Instant Photographs Work

The world of photography has changed since Edwin Land introduced a remarkable new invention to the world in 1947 - instant photography. Ever since the invention of the Polaroid camera, we could not imagine a world without it anymore.

I assume that nearly everyone knows how a Polaroid camera looks like and what needs to be done in order to take a picture, but do you actually know how the film is developed inside the camera? After pressing the shutter release button on the top of the device, the picture appears in a matter of minutes. In order to be able to fully understand the physics behind a Polaroid camera, it is essential to first be familiar with the basics of traditional photographic film.

Normal film is composed of plastic base coated with particles of light-sensitive silver compound. A black-and-white film has one layer of silver compound. When the film is exposed, the sensitive particles react to the light by changing their structure. To create an actual photograph, the film would then have to be treated with several chemicals. The instant film, however, already provides the developing chemicals in the different layers itself.  

The light-sensitive layer lies on top of the black base layer, which is under the image layer, the timing layer and the acid layer. This specific arrangement of the layers contributes a great deal to the quick developing, as it creates the environment for a chemical chain reaction. This reaction is triggered by the reagent, which is situated just above the light-sensitive layers. The reagent is composed of a mix of opacifiers, alkali, white pigments and other elements. As soon as the image is captured, the film sheet is ejected out of the camera through a pair of rollers, which spread the reagent material onto the sheet. As the reagent chemicals move through the individual layers, the exposed particles are changed into metallic silver. At the same time the developer dye is dissolved by chemicals and diffused up into the image layer. However, only the dyes from the unexposed layers will reach the image layer. The opacifiers and alkali in the reagent then react with the acid layer, making the opacifiers clear so that a visible image is created.

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The Napalm Girl

Describing three pictures: The Napalm Girl

Here's the link to Emina's blog:
The Napalm Girl

Little history of photography

Little History of Photography

As my life runs by I see the most innovative and stunning technological development when it comes to camera and other electronic equipment. I am a portrait painted between 1503 and 1506 and I am exhibited since the late 80s in the one of the world’s largest and most famous museums – The Louvre.  The historic monument is located in the heart of Paris. With its prestige the museum attracts over nine million visitors each year. 

We count the year of 1939 when one very special lady passed by.  “Look at this breathtakingly beautiful painted portrait”, said the well-dressed lady who was walking towards me. She wore an elaborately embroidered dress with attached petticoat and purple embroidery. I knew that she must have been from a royal family as she could afford taking pictures, which cost around 25 gold francs at that time. The values for the exposure time and brightness are coupled to one another.  It took a certain period of time until the picture was taken because the photographs were iodized silver plates exposed in the camera obscura, which had to have a proper light to become a pale grey picture. “I think I might have to retouch the negative”, said the lady with the pricy camera. Everyone around her was surprised I looked in an admirable way. At this time it was something special to have a camera.´, but as time went by it became commercialized and I saw more and more people taking pictures.

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Little History of Photography

Numerous people have contributed to the progress of photography ever since the early days of photography. Are you wondering who is talking to you? Yes, it is me, right here in the center of this picture painted by Leonardo da Vinci. 

A little while ago I have heard a fourteen-year old child, who was part of an exhibition group, complaining about how bad the quality of the pictures on his iPhone was. He moaned: “Why is this taking so long to take a decent picture?!” Let me tell you an interesting story in line with this statement.

I was painted during the Renaissance in the early 1500s and had been exhibited in one of the world’s largest and most famous museums since the late 1880s. I have seen the most innovative and stunning technological developments when it comes to cameras.

At this time, attempts to capture fleeting images were seen as ludicrous and blasphemous. Only after more than 100 years of unsuccessful attempts of searching for a means to capture those images, did Niépce and Daguerre succeed to inventing something that would forever change the nature of visual representation: photography.

The 1840s marked the beginnings of the evolution of photography. The daguerreotypes, as Daguerre dubbed his invention, were photographs on a highly polished, silver-plated sheet of copper exposed in the camera obscura. The values for the exposure time and the low light-sensitivity of the plates are coupled to one another.  This means that the process to acquire a pale grey image not only took a considerable period of time, it also cost 25 gold francs. It was not common to be in the possession of a camera. People who were able to take pictures were seen as noble and photography was associated with wealth.

Things developed so rapidly that by 1840 photography has soon become a professional tool. During the industrialization photography became commercialized and more affordable. Most of the miniaturists became professional photographers and encountered something new and interesting. This also paved the way for businessmen and young photographers. Many people moved to the cities and more and more owned their camera.

Now, if you think about complaining the next time on how much time your iPhone needs to take pictures, think about all inconveniences the artists have had with the development of the first camera.

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A day in life of Monika

It's a typical Monday morning. My alarm goes off at 4:45 and I am still in my cosy little land of dreams. To snooze it I know I simply have to tap the screen, so that's what I do automatically. I snooze the alarm to get at least another nine minutes of sleep.

Next I go to the bathroom to brush my teeth and wash my face. Then I prepare my beloved breakfast - a classical oatmeal with fruits. I really can't get enough of it so I literally eat it every single morning.

As I need to start working at 6 AM I leave the house around 5:30 AM. After a six-hour shift (or four-hour shift depends on how I have class that afternoon) I drive home to leave the car in the garage. At noon I sometimes have a quick meal before I head to university.

Usually I have three to four classes a day and am finished around three or five o'clock. When the weather is nice I like to walk home from university, otherwise I take the bus. When I arrive at home, my mother has prepared something delicious to eat. I am really thankful to have my family waiting for me at home and supporting me no matter what. In the evening I like to relax and do my homework (if there is some).