How the Manhattan Project Captured the First Nuclear Explosion: A Step-by-Step Guide

Introduction

On July 16, 1945, at 5:29:45 a.m. Mountain War Time, the world entered the nuclear age when the first atomic bomb—code-named “the Gadget”—detonated above the Jornada del Muerto basin in New Mexico. The Trinity test was not only a scientific triumph but also a monumental challenge for photographers tasked with documenting an event that would last only fractions of a second. How did they capture such an awesome and fleeting spectacle? This step-by-step guide draws from the methods used by the Manhattan Project’s photography teams, as detailed in Emily Seyl’s Trinity: An Illustrated History of the World’s First Atomic Test. By following these steps, you can understand the meticulous planning, equipment, and execution behind the historic photographs that still shock and inform us today.

Whether you’re a history buff, a photographer, or a student of science, these steps will reveal the ingenuity required to record the first nuclear fireball. Let’s break down the process used by photographer Berlyn Brixner and his colleagues.

What You Need

• Camera bunker – A reinforced structure (like the North 10,000 station) to protect operators and equipment from blast, heat, and radiation.
• Motion picture cameras – Two Mitchell movie cameras for high-quality footage, plus high-speed Fastax cameras for capturing sub-100th-of-a-second events.
• Turret mount – A rotating camera platform that allows the operator to track the fireball’s ascent.
• Welder’s glasses – Dark protective eyewear to safely view the blinding flash.
• Film stock – High-sensitivity black-and-white film, preloaded and tested.
• Loudspeaker system – For receiving countdown cues from the control bunker.
• Thick glass porthole – To shield the camera lens while allowing clear sight.
• Detonation timing system – Coordinated triggers to sync cameras with the explosion.
• Post-detonation analysis tools – Film developers, optical comparators, and measurement grids for scientific scrutiny.

Step-by-Step Instructions

Step 1: Construct and Arm the Photography Bunker

Begin by positioning a sturdy bunker about 10,000 yards from ground zero (hence the name “North 10,000”). The bunker must withstand the shockwave and heat while providing a clear line of sight to the test tower. Install a thick glass porthole in the wall facing the detonation point. Inside, mount a turret that can swivel vertically and horizontally. Place your Mitchell movie cameras on the turret, with Fastax cameras fixed to shoot through the porthole. Ensure all equipment is securely fastened to prevent vibration damage.

Step 2: Prepare the Cameras and Film

Load both Mitchell cameras with fresh film, checking that the sprockets and reels move smoothly. Set the focus manually to infinity, as the target is far away. For the Fastax cameras, select the highest frame rate available (thousands of frames per second) and install ultra-fast film. Test all cameras multiple times using a simulated countdown to confirm shutter timing. Label each camera and film canister with its location and purpose.

Step 3: Calibrate with the Countdown System

Connect a loudspeaker inside the bunker to the central countdown network. The photographer (like Brixner) must be able to hear every second. At T-minus 10 minutes, start the cameras in standby mode. At T-minus 1 minute, begin the final pre-roll sequence. For the Fastax cameras, trigger them exactly at T-10 seconds so they reach top speed precisely at detonation. Coordinate with the control bunker to ensure all cameras across the site (52 total) are synchronized.

Step 4: During Detonation – Capture the Fireball

When the countdown reaches zero, the 32 high-explosive lenses around the plutonium core detonate simultaneously, compressing the core and initiating fission. The first visible light appears in less than a hundredth of a second. At that instant, the photographer must put his head inside the turret and look directly toward the blast through welder’s glasses. Using the turret controls, he manually tracks the ascending fireball as it expands from a translucent orb to a multicolored, shape-shifting ball of flames. The Mitchell cameras roll continuously, while the Fastax captures the initial sub-second burst through the porthole.

Step 5: Secure and Develop the Film

Immediately after the shockwave passes (the cameras will have stopped automatically), retrieve the film reels from each camera. For safety, wait until the area is declared free of radioactive dust. Transport the sealed film canisters to a darkroom at the base camp. Develop the film using standard black-and-white chemistry, but take extra care because the extreme brightness may fog the negatives. Inspect each frame for clarity and density.

Step 6: Analyze the Footage for Scientific Data

Project the developed movies onto a gridded screen. Use the known distance from the bunker to ground zero to calculate the fireball’s size over time. Measure the rate of expansion, the shape changes, and the color transitions. Compare frames from different cameras to correct for parallax. (In the actual Trinity test, only 11 of 52 cameras produced satisfactory images, but those few were enough to provide the first accurate measurements of nuclear explosion effects.) Report your findings in scientific papers or historical archives.

Tips for Success

• Redundancy is critical – Deploy as many cameras as possible from different angles and distances. Even if one fails, others may succeed.
• Test, test, test – Practice the sequence with dummy runs. Timing errors or film jams will ruin your once-in-a-lifetime shot.
• Use protective gear – Welder’s glasses or similar are mandatory to avoid retinal burns from the intense light.
• Consider restoration – Decades later, old films may degrade. The images in Seyl’s book came from a 20-year restoration effort, so store your negatives in climate-controlled archives.
• Focus on key moments – The first few milliseconds reveal the most science. High-speed cameras are worth the expense.
• Learn from history – Review Brixner’s work. His ability to follow the fireball while blindfolded by the flash was a skill that came from meticulous preparation.

By following these steps, you can replicate the photography methods that gave humanity its first pictures of a nuclear detonation—and perhaps apply the same principles to other extreme scientific events. The Trinity test stands as a testament to both human destructiveness and human ingenuity, captured on film forever.