#labimages

[eleonorapontiggia-blog]

Third shooting in the laboratory for the practical project about fingerprints.

Technical notes:

-low power microscope

-camera Canon EOS 550D

-RGB colours

-magnetic fluo powder red

[eleonorapontiggia-blog]

Second shooting in the laboratory for the practical project about fingerprints.

Technical notes:

-microscope Zeiss Primo Star, high power

-lenses; 40x (0,65)  10x (0,25)  4x (0,10)

-camera Canon EOS 550D

-RGB colours

-magnetic fluo powder red

[eleonorapontiggia-blog]

Infrared camera

Beyond Perception: Art and Science collaboration

Photoshop editing; digital effect of the Kodak high speed infrared ektachrome film mainly used during the World War II to sight the enemy soldiers among the vegetation. The green of their uniform would stand out, while the green of the plants would become pink thanks to the peculiar composition of the infrared film.

The human visible spectrum goes from around 390 nm to 700 nm wavelength (of light) or from 430 THz to 770 THz if we consider the frequency. This interval comprehend the range of colours we can normally see with our eyes, the seven rainbow colours to be more clear. When we talk about radiations, we intend those colours which have either a longer or shorter wavelength than the visible spectrum and so that we cannot perceive (like X-ray for example). In order to make them visible to us, we need to avail ourselves with special instruments able to capture them and make them detectable to the human eye.

Considering the infrared rays we only need a camera sensible to them: actually, all digital cameras “are born” to be sensible to the infrared, but a filter on the sensor it is installed in order to block all the infrared rays and let only the visible ones pass. Therefore it is possible to record infrared rays only by using a camera without that special filter. To take pictures, one need to shoot two identical images, one with a filter that blocks the visible light on the lens and the other with a filter that blocks the infrared. Then it is possible to combine them on photoshop working with the colour canals of red, green and blue.

[eleonorapontiggia-blog]

UV lamp

Beyond Perception: Art and Science collaboration

The human visible spectrum goes from around 390 nm to 700 nm wavelength (of light) or from 430 THz to 770 THz if we consider the frequency. This interval comprehend the range of colours we can normally see with our eyes, the seven rainbow colours to be more clear. When we talk about radiations, we intend those colours which have either a longer or shorter wavelength than the visible spectrum and so that we cannot perceive (like X-ray for example). In order to make them visible to us, we need to avail ourselves with special instruments able to capture them and make them detectable to the human eye.

Considering the UV rays it is quite simple: there is no need of any kind of filters or special technologies, you can simply use a UV lamp as light sources pointed at the object of your interest and a regular camera (SLR or DSLR) to record. What the UV lamp does, is to excite the fluorescent particles of the object making it fluorescent, so if the subject doesn’t have any fluorescent part, you won’t see any differences from a regular light sources. Therefore one either has a fluorescent material to analyse, or it is possible to make it fluorescent by contaminating it with some chemicals.

[eleonorapontiggia-blog]

Microscope 

Beyond Perception: Art and Science collaboration

The microscope was invented in 1590s by the Dutch spectacle-maker Zacharias Janssen and then developed by Galileo Galilei at the end of 1600. Nowadays there are several type of this machine, each of which able to detect a particular aspect of the object observed. What a microscope does is basically to magnify the image of an object through a very sophisticated lens. Before the invention of photography, a scientist had to replicate the image seen though the machine, by drawing it himself (the micrographia of Robert Hooke). Nowadays, despite the incredible development of both photography and microscopy, there are still some limits in shooting images directly from the enlarger. You can put your camera on top of the microscope by a special adapter, but you have to make use only of the machine’s light having no control on the aperture and so you’ll have a poor depth of field and the picture will result rather flat. Another limit is the focus, it is incredibly difficult to obtain high quality sharp images, the smallest movement of the camera or the machine will change the focus on the image and moreover, what you see though the camera is not actually what the camera will record, so you need to make adjustments based on intuition and experience.

Here I have analysed some common hair in the laboratory with a high power microscope.

[eleonorapontiggia-blog]

High speed flash

Beyond Perception: Art and Science collaboration

The first technology we looked at was the High Speed Flash. From the outside it seems a regular flash, but what it does is to produce a sequence of flashes at very high speed (you can actually regulate it as you wish) in very short amount of time. In this way it is possible to record the movement by dividing it in to different photograms all belonging to a single shot; the final result could be compared to the effect produced by a long exposure but more sharp and accurate. This type of technology was largely used by Harold Edgerton who created the notable picture Shooting the apple looking back at the work of Muybridge and Marey and their study on movement.