Basic Photography Course

select a wider aperture to control depth of field, start by
setting your main flash at one-half or one-fourth power
and adjust your fill flash appropriately.

Adjusting lighting ratios by flash-to-subject-

distance is another method to control lighting ratios. An
easy way to calculate footage for a 3:1 ratio with two
lights of equal intensity is to think of the full f/stops (2,
2.8, 4, 5.6, 8, 11, 16, 22, etc.) as distances in feet. Place
the main light at the desired distance closest to one of
the "f/stops," and place the fill light at the distance
indicated by the next larger number; that is, 5.6 feet and
8 feet or 16 feet and 22 feet, and so on.

Another easy method to control the lighting ratios

using an automatic electronic flash is to use the flash
unit in the automatic mode. When set in the automatic
mode, the flash-to-subject distance is not supercritical,
and there is some leeway as long as the flash units are
within their operating range.

To obtain a 2:1 lighting ratio, you simply have both

flash units set at the same automatic setting and at
approximately the same distance from the subject. For
a 3:1 lighting ratio, use the same automatic setting and

approximately the same flash-to-subject distances, but
set the fill flash at twice the film speed as the film being
used (main flash setting). For a 5:1 or even higher
lighting ratio, use the same automatic setting and
approximately the same flash-to-subject distance and
set the fill flash at four times more than that of the main
flash, and so on.

Any lighting ratio can be obtained when using an

automatic flash unit. By controlling the power output

intensity, adjusting the film speed setting, changing the

main and fill flash distances, or a combination of the
three, you can manipulate the lighting ratio easily to any
ratio. As with any stage of photography, practice and
testing with your camera and flash combinations in
various situations produces the best results.

SYNCHRO-SUNLIGHT

Bright sunlight, used as the only means of

illumination for an exposure, can produce deep
objectional shadows on a subject. When a flash unit is
used as a fill-in source of illumination, it reduces these
shadows and is known as synchro-sunlight photography.

Improperly handled, the synchro-sunlight

technique can produce an effect that makes the
photograph appear as if taken at night with a single flash.
This effect occurs when the flash illumination is more
intense than the sunlight.

The first step for proper exposure with synchro-

sunlight is to calculate the correct exposure for daylight,
and set the shutter speed and f/stop as though a flash is

not being used; however, keep in mind when using a
focal-plane shutter, the shutter speed must be
synchronized with the electronic flash unit. Avoid using
a fast film in bright sunlight when using a camera
equipped with a focal-plane shutter. In this case, you are
limited only to your aperture to control the exposure of
the film, because your shutter speed is nonadjustable. A
leaf shutter has an advantage over a focal-plane shutter.
When a leaf shutter is used, it provides more control over
depth of field since the shutter synchronizes at all shutter

speeds.

When you are using an automatic flash, the same

principles apply for synchro-sun that were explained in
the section for lighting ratio. The sun is used as the main
light, and your camera settings are determined directly
from your light meter. The easiest method is to set the
film speed (ISO) on your flash unit to twice the film
speed being used for a 3:1 lighting ratio and four times
the film speed being used for a 5:1 ratio. A fraction of
the manual power output can also be used to achieve the
desired lighting ratio.

Remember to compensate your exposure by

opening up two f/stops for a backlit subject and one
f/stop for a subject that is sidelighted when taking your
light meter reading from a distance. For color
photography, you should normally use a 2:1 or 3:1
lighting ratio. For black-and-white photography, a ratio
of 3:1 to 5:1 is acceptable.

MULTIPLE-FLASH UNITS

Multiple flash is the use of two or more flash units

fired in synchronization with the camera shutter. The
flash units can be auxiliary flash units, connected to the
camera by extension cords, or they can be slave flash

units. Slave units usually have self-contained power
sources and are fired with a photoelectric cell when light
from a master flash unit strikes the cell of the slave unit.

With multiple flash, exposure calculations are based

on the distance between the subject and the flash unit
that produces the most intense illumination to the
subject; therefore, you can have numerous auxiliary
flash units or slaves for a scene and only calculate your
exposure from the mainlight source. All other flash units
should be equidistant or at a greater distance from the
subject as compared to the flash unit on which the
exposure is based.

5-35

contents

Basic Photography Course

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DOFMaster for Windows On-line Depth of Field Calculator DOFMaster for Mobile Devices On-line Depth of Field Table Hyperfocal Distance Chart Articles FAQ Recommended Books Support Contact Links Home As an Amazon Associate I earn from qualifying purchases.	contents <- previous page next page -> select a wider aperture to control depth of field, start by setting your main flash at one-half or one-fourth power and adjust your fill flash appropriately. Adjusting lighting ratios by flash-to-subject- distance is another method to control lighting ratios. An easy way to calculate footage for a 3:1 ratio with two lights of equal intensity is to think of the full f/stops (2, 2.8, 4, 5.6, 8, 11, 16, 22, etc.) as distances in feet. Place the main light at the desired distance closest to one of the "f/stops," and place the fill light at the distance indicated by the next larger number; that is, 5.6 feet and 8 feet or 16 feet and 22 feet, and so on. Another easy method to control the lighting ratios using an automatic electronic flash is to use the flash unit in the automatic mode. When set in the automatic mode, the flash-to-subject distance is not supercritical, and there is some leeway as long as the flash units are within their operating range. To obtain a 2:1 lighting ratio, you simply have both flash units set at the same automatic setting and at approximately the same distance from the subject. For a 3:1 lighting ratio, use the same automatic setting and approximately the same flash-to-subject distances, but set the fill flash at twice the film speed as the film being used (main flash setting). For a 5:1 or even higher lighting ratio, use the same automatic setting and approximately the same flash-to-subject distance and set the fill flash at four times more than that of the main flash, and so on. Any lighting ratio can be obtained when using an automatic flash unit. By controlling the power output intensity, adjusting the film speed setting, changing the main and fill flash distances, or a combination of the three, you can manipulate the lighting ratio easily to any ratio. As with any stage of photography, practice and testing with your camera and flash combinations in various situations produces the best results. SYNCHRO-SUNLIGHT Bright sunlight, used as the only means of illumination for an exposure, can produce deep objectional shadows on a subject. When a flash unit is used as a fill-in source of illumination, it reduces these shadows and is known as synchro-sunlight photography. Improperly handled, the synchro-sunlight technique can produce an effect that makes the photograph appear as if taken at night with a single flash. This effect occurs when the flash illumination is more intense than the sunlight. The first step for proper exposure with synchro- sunlight is to calculate the correct exposure for daylight, and set the shutter speed and f/stop as though a flash is not being used; however, keep in mind when using a focal-plane shutter, the shutter speed must be synchronized with the electronic flash unit. Avoid using a fast film in bright sunlight when using a camera equipped with a focal-plane shutter. In this case, you are limited only to your aperture to control the exposure of the film, because your shutter speed is nonadjustable. A leaf shutter has an advantage over a focal-plane shutter. When a leaf shutter is used, it provides more control over depth of field since the shutter synchronizes at all shutter speeds. When you are using an automatic flash, the same principles apply for synchro-sun that were explained in the section for lighting ratio. The sun is used as the main light, and your camera settings are determined directly from your light meter. The easiest method is to set the film speed (ISO) on your flash unit to twice the film speed being used for a 3:1 lighting ratio and four times the film speed being used for a 5:1 ratio. A fraction of the manual power output can also be used to achieve the desired lighting ratio. Remember to compensate your exposure by opening up two f/stops for a backlit subject and one f/stop for a subject that is sidelighted when taking your light meter reading from a distance. For color photography, you should normally use a 2:1 or 3:1 lighting ratio. For black-and-white photography, a ratio of 3:1 to 5:1 is acceptable. MULTIPLE-FLASH UNITS Multiple flash is the use of two or more flash units fired in synchronization with the camera shutter. The flash units can be auxiliary flash units, connected to the camera by extension cords, or they can be slave flash units. Slave units usually have self-contained power sources and are fired with a photoelectric cell when light from a master flash unit strikes the cell of the slave unit. With multiple flash, exposure calculations are based on the distance between the subject and the flash unit that produces the most intense illumination to the subject; therefore, you can have numerous auxiliary flash units or slaves for a scene and only calculate your exposure from the mainlight source. All other flash units should be equidistant or at a greater distance from the subject as compared to the flash unit on which the exposure is based. 5-35 contents Basic Photography Course <- previous page next page ->	As an Amazon Associate I earn from qualifying purchases.
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