Liquid emulsion is similar to the emulsion found on photo paper, but in liquid form so it can be coated on a range of surfaces. We prepared a range of surfaces including wood, fabric and different types of paper and card by painting them with a few layers of PVA glue. When they were dry we moved them to the dark room and coated them with liquid emulsion. We projected the films onto them in the same way as normal photographic paper, and used a test strip to see how long they should be exposed for. I found that they needed longer than photo paper to produce an image, and exposed most of them for around 12 seconds.
I experimented with exposing photos onto a few different materials. I tried one on newspaper which didn't work at all. The image only appeared in streaks where the liquid emulsion had been painted on, and when I put it in the water it was washed off the newspaper. I think it may have needed more coats of PVA glue, and the liquid emulsion painted on more carefully or in more layers. I also printed photos onto two types of fabric: a white cotton with grey embroidered leaves, and a textured fabric with painted wave shapes. The images came out quite well on both the fabrics but not on the patterned parts. I think this could work quite well depending on the photo being printed. It would probably need to be more of a pattern based image so that the two would overlap and combine well together.
Thursday, 25 February 2016
Infrared Photography


Infrared film is sensitive to the full spectrum of visible light and also to infrared radiation. This means the images differ from normal black and white film because normal film is only sensitive to visible light in order to replicate what we see. The effect of infrared film is most obvious when photographing leaves and plants because they reflect a lot of infrared radiation. This should mean they appear brighter in photographs. There are also some types of dyes and pigments that reflect more infrared radiation than others, so would stand out more.
There are different types of infrared films, some more extreme than others meaning they are sensitive to longer wavelengths which allows them to pick up more infrared radiation. The film we used was Rollei Infrared IR 400 which has sensitivity up to 820 nanometers(nm) with filtration. I didn't use a filter on my camera so the sensitivity will have been lower than this. Wavelengths of infrared radiation range from around 700nm to around 1,000nm so the film I used was one of the least sensitive. This means it produces a less extreme effect but is easier to handle and less likely to be ruined by light leaking into the film canister. Most infrared films can only be inserted or removed from the camera in complete darkness but this film can be handled in subdued light.
I developed my films in developer for 10 minutes, agitating every 30 seconds; then stop bath for 30 seconds, agitating constantly; then fixer for 5 minutes. I then rinsed it with running water for 30 minutes. I exposed some of my photographs onto photographic paper in the dark room, using a test strip of different exposure times to work out how long was needed. I exposed most of my images for 3 seconds.
I don’t think my photos were entirely successful because although some of them were quite crisp and detailed, a lot of them looked washed out and foggy. The foliage didn’t stand out much and they didn't have the high contrast of many black and white infrared photos. This could be because I didn't use a deep red or R72 filter which would have produced stronger effects, and may also be the result of some light leaking onto the film when I was developing it or moving it in or out of the camera.
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