Peak of Action is an old technique to capture a sharp image of a moving subject. I’ve written about it many times but this is the first time I actually mentally thought of it as a way to capture an image in an air to air photo mission. The best way I know of explaining Peak of Action is a basketball. When you are dribbling a basketball, it travels up and down. Peak of Action happens twice during this travel. It happens when at the top and bottom of its travel as it stops for just a heartbeat before changing its course of travel. That moment for example when it hangs in the air before falling, that is the Peak of Action. Photographing the ball that moment, it will be sharp because it is not moving anymore. This is the technique I applied to this photo.
There are two directions of movement in this photo. Direction A is the direction the subject aircraft (Zero) and the photo platform (A36) aircraft are traveling. Since they are both traveling at the same speed, as far as the film plane is concerned, they are not moving at all. The Zero, the subject, as the film plane sees it is not moving so not matter the shutter speed, it’s sharp. So shooting still at 1/40, the Zero is sharp but the prop is blurred. That’s because the prop is traveling perpendicular to the film plane. With that opposing path of travel, you can effect the props sharpness with shutter speed. Direction B in which the prop and the Spitfire are traveling is perpendicular to the film plane, their motion can be frozen or blurred by the shutter speed. Since I want the props blurred I shot with that 1/40 shutter speed but the movement of the Spitfire caused it to be completely blurred at that 1/40. How to freeze the Spitfire in its attack then? Yep, Peak of Action! It was that easy! As the Spitfire would arc up in its attack, there was a moment when it stopped, it hung for a moment before sliding back under the Zero. I was in a A36 shooting with the D4s / 80-400VR3, I was “fixed” so it was up to pilots to make the photograph come to life. I just turned to an old technique to freeze the motion while still showing the motion with shutter speed. It’s the craft of photography in action.