One of the biggest challenges with capturing such short-duration events like high explosives is estimating proper exposure. To prevent the image from completely blowing out in the bright blast, we had to dial in sensor sensitivity, lens aperture and exposure time, while also setting up the frame in a way that the light from the det cord and blast itself could be used to light the rest of the image. We wanted a cohesive overall image, not just a fireball in a black void. By using high-output lighting we attempted to raise the background exposure to a level where we could maintain some visibility of the surroundings.
Some of the exposures we ended up capturing were in the neighborhood of ISO 50,000 and a shutter time of 3 microseconds for capturing at 309,000 frames/second. That resulted in a total frame resolution of 512x384px. The long lenses we had onsite let us crop in tighter on the action while maintaining safe standoff to protect the equipment.