الضوء الخاطف ( الفلاش والحركة ) .. تقنيات خاصة .. كتاب التصوير الضوئي

Flashlight (flash and motion) .. Special techniques .. How to take the most beautiful pictures .. Photography book

Special techniques

Flashlight (flash and motion)

Sleight of hand: Hasselblad with electronic flash aperture 11 Ectachrom EX

Without using flash, the machine's ability to freeze motion depends on the duration of the image capture and the film speed. Its ability to do so is directly related to them. A speed of 1000/1 second can stop fast motion: a running person, a cyclist, or
something falling, etc.. Then the quality of the image depends on the amount of light available, especially if we need a
wide depth of field.

With electronic flash, the duration of the flash determines the amount of motion that can be stopped and the shutter speed is of no importance. Taken with a small aperture: 16/F or more. Flashes designed for oscillation photography, each flash being shorter than 1/1000th of a second, allow you to stop very fast movements that are not noticeable to the eye: the breaking of a drop of water, the flapping of a (small bird's) molar wings, or even a gunshot.

The oscillating flash gives off a series of flashes whose frequency can be adjusted.

For the image of the magician, I made myself a device to press the shutter button – a simple rotating contact that emits flashes at frequencies ranging from 1/50th of a second to 5 seconds. When I use the oscillating flash, I manage to make the different parts of the subject light up each section separately: this prevents the parts of the subject that do not change position from being exposed to too much light. It is advisable to work in front of a very dark background to show the different positions of movement. For the image on page 171, a single very short flash with the light directed towards the background.

Wine Bottle: Hasselblad Long-burner lens with electronic flash 16 Aperture Actachrom EX

These two images show the difference between a conventional (black and white) lens and a stenoptic (colour) image. I made my stenoptic box in a shoe box with a small hole punched at one end. I made the box light-tight, meaning that light could not enter it, and I attached colour film to the inside of the box opposite the stenoptic. I then made a second shoe box with a larger hole at one end than the stenoptic and a piece of galvanised paper at the other end to use as a semi-gloss bottle. The small diameter of the stenoptic and the slow speed of the colour film required a strong light to illuminate the subject. So I created a lighting surface made up of 36 side-by-side electronic flashes as shown in the drawing. I used the stenoptic box to make the frame and the other box - replaced at the last minute - to take the picture. This stenotype photograph has rare illumination.