‘Picturing the Cosmos: Hubble Space Telescope Images and the Astronomical Sublime’, Elizabeth A. Kessler.

The chapter ‘Translating Date into Pretty Pictures’ dissects the way ‘Astrophotography’ is ‘made’ from data, where data from ‘flexible image transport files’ (FITS) are downloaded from the Hubble Telescope before inputted into imaging programs such as ‘IRAF’ software or more recently via the ‘FITS Liberator’ plugin for Adobe Photoshop. Astrophotographers then work through a series of processes to render this data and ‘make visible’ areas of the data which lie beyond the electomagnetic spectrum.

The Electromagnetic Spectrum. Ultraviolet or Infrared light may be collected as data by the Hubble Telescope, but this is invisible to the human eye.

These processes include:

Building Composites – stitching together multiple exposures that have been photographed with different filters.

Selecting Contrast – ‘revealing’ structures of the unseen such as nebula/gas clouds (some Astrophysicist’s match each pixel to lumen/light intensity data and have a closer association with nature)

Determining Colour – this isn’t scientifically assigned, although blue often characterises the least energy and red the most energy. Kessler repeatedly states that some astrophotography aesthetics are decided by ‘trained judgement’ or through a set of pre-determined algorithms associated with a particular institution.

Kessler cites: “It’s important to use a different color for each data set. Otherwise, distinct information from each of the data sets is lost.” (Rector et al., “Image-Processing Techniques for the Creation of Presentation-Quality Astronomical Images,” p. 609)

Cosmetics – known as ‘Cosmetic Cleaning’, where cloning within Adobe Photoshop removing stray cosmic rays and difference in background colour from composite blending. Interestingly, ‘diffraction spikes’ (rays of light caused by telescope optics) are often kept, or even added into images where they don’t exist, they appeal to the aesthetic contemplation of ‘starry skies’.

“Perception and representation, number and image, index and symbol–the hybridity of the Hubble images raises a question that haunts all scientific images: What is their relationship to the phenomena they purport to represent?” (2012, p. 128)

Screenshot from The Hubble Heritage Project’s website.

Kessler makes useful links to existing philosopher and critical thinkers:

• David Batchelor, Chromophobia. London:Reaktion Books, 2000
• Walter Benjamin, “The Task of the Translator” and The Arcades Project, p476 ‘
• Immanuel Kant, Critique of Judgement. 1790.
• Ansel Adams, The Negative (describes physical changes in photography: dodging and burning etc.)
• William Mitchell, The Reconfigured Eye: Visual Truth in the Post-Photographic Era, 1992. “[…] an interlude of false innocence has passed. Today, as we enter the post-photographic era, we must face once again the ineradicable fragility of our ontological distinctions between the imaginary and the real, and the tragic elusiveness of the Cartesian dream. We have indeed learned to fix shadows, but not to secure their meanings or to stabilize their truth values; they still flicker on the walls of Plato’s cave.” (p. 225)
• Time Magazine, October 25, 1989, “150 Years of Photojournalism”. A modified image of Buzz Aldrin walking on the moon shows all seven astronauts, carrying the caption “A picture of something that never took place”.
• Bruno Latour “reversible chain of transformations” – a series of changes that link messy phenomena in the world to a representation. (Latour, Pandora’s Hope, p71)

Reference:
Kessler, E. A. (2012) Picturing the Cosmos: Hubble Space Telescope Images and the Astronomical Sublime. Minneapolis; London: University of Minnesota Press.