A new technological development will make it possible to photograph objects, people and animals while they are moving, while maintaining the sharpness of the image
We will no longer hear the phrase "Don't move! Taking pictures!". Researchers from Tel Aviv University have developed a photography process that allows sharp and clear photography of moving objects without the displacement being "smeared" on the image. The development includes an optical component, which encodes displacement information and performs adaptive digital processing.
color the movement
"The term 'long exposure' always refers to the speed of the imaged object," explains doctoral student Shay Elmelam from the School of Electrical Engineering At the Ivy and Alder Fleishman Faculty of Engineering, who developed the integrated processing method, under the guidance of the late Prof. Emmanuel Marom and Dr. Raja Jiris. "When photographing a racing car, even an exposure of one-tenth of a second may be too long, and if the subject is a person walking - a long exposure will be considered as one of a second or more. In the approach accepted today, a lens is designed that will produce the best image, i.e. the most similar to what the human eye sees, and then they try to solve the distortions with digital processing. But as anyone who owns a cell phone that is equipped with a camera knows - it is not always effective, so it is still very difficult to photograph moving objects."
By an integrated design of the optical components and the algorithms that process the images, Almelam and his colleagues planted in the raw image clues to the movement data, which the algorithm knows how to read and correct. The clues were planted using two optical components, which are integrated into a normal lens: a transparent phase plate developed by the researchers, and a commercial electronic focus lens. The plate contains an optical-micrometric structure, designed to create a dependency between the color and the focus, while the focus lens is timed so that it performs a gradual change of focus while shooting. As a result, moving objects are painted in different colors while moving. The color coding allows the algorithm to decipher the direction and speed of the object's movement, which allows it to correct the smear and restore the sharpness of the image. The results of the innovative research were published in the prestigious journal Optica.
The end of smears
"In every fraction of a second of exposure, our camera takes pictures in a slightly different way, so that the smearing of a moving object will not be uniform, but will change with the movement," explains Elmelam. "To understand where and how fast the object is moving in the image, we use color. So for example, a white ball that I suddenly throw into the frame will be painted in different colors along its movement, similar to the transmission of light through a prism, and according to these colors our algorithm will know where the ball was thrown and at what speed, and thus it will be able to correct the smearing. If in a normal camera we would see a white trail, which would distort the sharpness of the entire image, in our camera the final result will be a clear and focused white ball."
According to Elmelam, the optical system they developed can improve any camera at minimal cost. "The potential is very wide: from basic use such as phone cameras, to research, medical and industrial uses, and even controllers of production lines, microscopes and telescopes. Everyone suffers from the same problem of smearing, and we offer a systemic solution to this problem." The development has already been registered as a patent, and several companies have already expressed interest in purchasing it through Ramot Company for the commercialization of the technology of Tel Aviv University.
Prof. Marom died during the research, and the published article was dedicated to his memory. The late Prof. Marom was one of the founders of the Faculty of Engineering at Tel Aviv University, he served as Dean of the Faculty in 1983-1980, and as Vice President of the University in 1997-1992. After retiring, Prof. Marom continued to engage in active research and guide graduate students, right up until his last day.
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