Ecole Polytechnique Fédérale de Lausanne master’s student Thibault Kuntzer has focused his efforts on an image taken by the Hubble Space Telescope – the most distant photo of the universe ever taken. As part of a semester project, he tested and increased the efficiency of an image-processing program that improves images taken by the telescope – a feat that could be of interest to astronomers.
“Astronomy is a mélange of every aspect of physics. The images are beautiful, but to understand them, you have to be multidisciplinary,” he said. “To interpret an astronomical image, it’s necessary to clean it up and make it clearer; astrophysicists call this “deconvolution.” To do this, you have to understand the characteristics of the sensors, such as their sensitivity to each color. Then, by applying mathematical and numerical processing methods, you can reduce blurriness while still conserving as much of the raw data as possible.”
Frédéric Courbin, senior scientist in EPFL’s Laboratory of Astrophysics, developed a custom-made technique for processing each image. The trick with this approach is to find the right calibration; for example, as a function of the sensor used. Kuntzer took on this painstaking job – more than 200 hours in all – in order to come up with the right algorithm. “It takes nearly 60 hours on a laptop computer to process a very high-resolution 100-megapixel image.”
This personalized processing program improves the image resolution, revealing twice as much detail. Applying the technique to the image of the farthest galaxies in the universe would enable it to be validated more easily, given that this image has already been analyzed numerous times. This would also reveal whether the technique was able to unveil new information. The method could then be used for research requiring very high-resolution images. For example, astronomers need to see every detail in order to study deformations known as gravitational mirages, which appear on far-off objects when a massive body is in front of them.
