How does instant photography work?

 

Polaroid film is essentially one big chemical reaction. When you take a picture with a Polaroid camera, the shutter opens and quickly captures the image. It takes in the patterns of light and imprints the image onto plastic film that is covered with silver compound. This is when the photo develops. On the film there are three silver compounds. The top layer is sensitive to blue light, the next layer is sensitive to green light and the bottom layer is sensitive to red light. When you expose the film, the sensitive grains at each layer react to the light of that color, creating a chemical record of the light and color pattern. Each color layer is situated above a developer layer which contains dye couplers. There are four chemicals waiting to react, namely the developer layer, the acid layer, the timing layer and the image layer. The chemicals get set off by a reagent. A reagent is a substance used in chemical reaction to detect, measure, examine or produce other substances. It is a mixture of white pigments, opacifiers and alkali. Opacifiers and alkali are especially important since the opacifier, a chemical that protects a newly ejected image from light and then slowly dissolves away, works as a light blocker and the alkali as an acid neutralizer. The reagent is collected in a blob at the border of the plastic film sheet, away from then light-sensitive material. When you snap a photo, your instant camera automatically ejects the picture in between two metal rollers. As the film exits, these rollers push the reagent on the white plastic borders onto the silver compound, spreading the reagent across the film. This starts a large chain of chemical reactions. First, the reagent causes the four layers (developer, acid, timing and image layer) to react. This then causes the silver compound layer to process, thus producing blue, green and red light patterns which turn into an image. The timing layer protects the film from light exposure until the film is fully developed. This final reaction is what causes the illusion of the image being formed right before your eyes. 

  

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Group blog post - Rate the instructions of camera lucida by Tim Hunkin

Tim Hunkin’s instructions about how to make a camera lucida are not very helpful due to various reasons. It does not seem like the author was very familiar with the steps of process. First of all, only by looking at the instructions as a whole, the paper does not look very professional, perceptible from the format, layout and style. The instructions seem to be scribbled down by hand and rather resemble a comic than a clear set of instructions. What is more, the steps are neither written in logical order nor numbered, thus making it hard to know for sure what should be done first, what second and so on. It also might have been more helpful to use keywords instead of writing one, often too long, sentence followed by another. His instructions also often contain multiple actions which need to be done at the same time which inevitably creates confusion. Normally, each step should only be a baby step in the whole process. Secondly, his instructions require previous knowledge which, however, should not be the case when creating well-written instructions. Thirdly, Tim Hunkin did not include a list of items required to build a camera lucida. Fourthly, no warnings as pre-steps are included to indicate that something is critical to be done before something else. In the end the author gives some advice regarding the drawing, as the camera lucida is supposed to be an optical device used as a drawing aid by artists. However, expressing personal opinions, preferences or choices should be avoided, and instructional texts should be strictly factual statements that tell the reader to perform an action. On the plus side, he did begin writing the instructions with a verb, asking the reader to do something, which is essential when giving instructions. All in all, Tim Hunkin’s instructions might mislead the reader and make him end up with different results. 

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Description of the 'Napalm Girl'

The photo ‘Napalm Girl’ was taken by Huynh Cong Ut during the Vietnamese War in 1972 in Trang Bang. The black-and-white photograph shows five children running along a road followed by five soldiers. They are hurrying along a deserted road, as though driven by shuddering fear. Behind them there is a thick cloud of black smoke. In the foreground, on the left side of the road, there is a boy who is wearing a plain white shirt and black shorts and has his mouth opened, crying in utter despair. His eyes stare in disbelief. Behind him there is an about four-year-old boy wearing nothing but a long-sleeved, white button-down shirt. He is turning his head back to the soldiers and to the huge cloud of smoke in the background that seems to be coming closer and closer. In the middle of the road is a nine-year-old naked girl, the ‘Napalm Girl’, who is screaming and running toward the camera in what seems to be agony. Her outstretched arms and her wailing face set the tone of the picture. She cries as if her heart has been wrenched out of her little body. Like the cold breath of a grave, her face seems to cut every person’s soul. On the right hand side of the road a small boy who seems to be bewildered, not knowing what is happening, and a desperate girl - possibly brother and sister - run hand in hand. They are the only fully clothed children in the picture, missing nothing but their shoes. Whereas the scared and desperate children all seem to run for their lives, the four soldiers leisurely walk behind them. They are dressed in their uniforms, helmets and carrying firearms. Their facial expressions are not really discernible, as they are situated too far back in the picture. Another person is visible in the very back of the picture, right in front of the thick, massive cloud of smoke which makes it impossible to see what could be behind it. Both sides of the road are surrounded by grass and some bushes.

A day in the life of…ME

A typical day in my life looks like this: I get up pretty early (around 7.30) in order to profit fully from the day. First of all, I have breakfast. Right after, I usually have to go to university until at least lunchtime. After having attended all of my classes, I have lunch (either alone or as I prefer - with some friends) and try to get done some of my many homework assignments. Now the fun part of my day beings: whenever time allows I go meet up with some friends (either for having some coffee, for simply enjoying the sun in one of Graz’s numerous city parks, for going shopping or just for hanging around). Then, having reloaded all of my energy, I usually try ( ! ;) ) to get some studying done. After one or two hours of more or less intensive studying, I go out again to do some sports which helps me to relax. Depending on which weekday it is, my evening program either consists of going out, relaxing at home with a good book or movie, or simply listening to my favorite music. Unfortunately, however, I often have no choice but to stay at home to study for exams.