Here's how 16-year-old Pune boy created this viral Moon photograph
Prathamesh Jaju, a tenth-grader from Pune, made waves on the internet with a tack-sharp image of the Moon. The teenager claims to have processed 50,000 images over 40 hours to create the final picture. The self-proclaimed amateur astronomer and astrophotographer said he wants to become an astrophysicist and study the universe. Here's how he created the viral image.
Captured frames took up 100GB of space
Speaking to ANI, Jaju said that he captured the images on May 3 over the course of four hours starting 1 am. Jaju elaborated on the equipment used to capture the 50,000-odd images in his Instagram post. He told ANI that the raw data occupied 100GB of space and after post-processing the files totaled 186GB. The final picture took up to just 600MB.
Jaju photographed what is known as the third-quarter mineral Moon
The third-quarter Moon appears around dawn and sets around midday. It is easily identifiable since one half of it is lit by sunshine and the other is engulfed by its own shadow. "Mineral Moon" is a term used to describe pictures color-graded to enhance the brownish-orange and blue color patches on the surface. The colors are due to minerals in the lunar soil.
Prathamesh Jaju's viral image on Instagram
Jaju relied on professional-grade equipment borrowed from Pune's astronomy club
Jaju said that he used a Celestron 5 Cassegrain OTA (Optical Telescope Assembly) borrowed from Pune's oldest amateur astronomy club Jyotirvidya Parisanstha (JVP). He took formal lessons in astronomy at JVP three years ago. He then used a ZWO ASI120MC-S camera to record 38 videos, each comprising around 2,000 frames. The best 50,000 frames out of approximately 76,000 were post-processed.
What makes the ZWO ASI120MC-S camera better suited for astrophotography?
Although the camera comprises just a 1.2MP CMOS sensor that interfaces with a computer over USB, its color profiles and lens assembly design is specially calibrated for astrophotography. The camera weighs just 300 grams but can record exposures as long as 1,000 seconds.
Telescope focal length multiplier, motorized celestial body tracker for assistance
The GSO 2X BARLOW focal length multiplier attachment doubles the focal length of the aforementioned telescope from 1,500mm to 3,000mm. In this case, it made the Moon appear twice as close to the observer. The telescope, camera, and focal length multiplier were coupled to a SkyWatcher motorized tracker so celestial bodies don't go outside the telescope's field of view.
Exposure bracketing composites the bright parts of multiple images
Jaju combined 50,000 images to create a single master photograph using two techniques called bracketing and stacking. Exposure bracketing (commonly known as HDR) is a technique using which the same subject is shot at different exposures (longer exposures result in brighter pictures). The bright parts of images are combined into a single image (composited) to create a vivid final picture.
Focus stacking combines in-focus bits from multiple photographs
Stacking is short for focus stacking. Due to the inherent camera lens optics, objects farther away from the center of the frame are blurry and/or exhibit artifacts such as fringing and geometric distortion. For this reason, astrophotographers record multiple images focusing on different parts of the same celestial body. The images are then "stacked" in post-processing to combine the sharpest bits from each photograph.
Modern image manipulation software completely automate stacking, exposure bracketing
Exposure bracketing enhances the details visible on the dark half of the Moon Jaju photographed. Additionally, the entire Moon is tack-sharp because the sharpest bits from 50,000 photographs were composited to achieve the final image. In fact, popular image manipulation software such as Adobe Photoshop usually come with built-in stacking and bracketing tools that completely automate the process.
Stunning photograph stands testament to Jaju's grit and resourcefulness
The astrophotography experts we had consulted contended that, although impressive, such images aren't uncommon in the community. But that's an unfairly cynical dismissal of Jaju's initiative and resourcefulness. Although some may argue the results are impressive primarily due to the equipment, it is heartening to witness the rare few adolescents like Jaju choosing such enlightened scientific pursuits over the low-hanging fruit of TikTok fame.
