Fill Flash

There are times that an electronic flash can be used to overcome problems in natural light to control contrast between highlights and shadows in a scene. In strong light there can be several f-stops difference between highlight and shadow areas. This is more than films can handle. In these situations, fill-in flash can create a balance and keep detail.

The Mystery of Fill In Flash

Mastering fill in flash is essential for outdoor portraiture.

Step One:

Set the ISO on the flash gun to the ISO film you are using

Step Two:

Set your shutter speed to 1/125th of a second
(check your camera sync speed is compatable)
Take the ambient light meter reading
Use your camera or a handheld meter to determine your aperture setting

Step Three

Adjust your flash aperture setting as follows
Overcast weather: Two stops less than the camera setting
Sunny weather: one stop less than the camera setting
Very Sunny weather: The same aperture setting as the camera

Camera Setting	Overcast Flash Setting	Sunny Day Flash Setting	Very Sunny Day Flash Setting
f2.8			f2.8
f4		f2.8	f4
f5.6	f2.8	f4	f5.6
f8	f4	f5.6	f8
f11	f5.6	f8	f11
f16	f8	f11	f16
f22	f11	f16	f22

Note : Dont change your shutter speed, that way with practice you will learn what settings to use.

Tip:If your lens will not go two stops less, CHANGE your ISO.

Though making dark places brighter is the primary use of flash, the next-best place to use it, surprisingly enough, is outdoors in bright sunlight. One of the problems of taking pictures--especially individual or group portraits--by midday sun is that the harsh lighting creates deep, distracting shadows. In people pictures this usually means dark eye sockets and unattractive shadows under the nose and lips. Fill-in flash lightens these shadows to create more attractive portraits.

Fill-in flash isn't limited to taking pictures of people: use just a gentle kiss of flash to open up the deep shadows in close-ups of flowers or architectural details.

Shutter speed does not affect flash exposure.

Flash exposure is affected by

aperture,
ISO,
and camera-to-subect disctance.

NOT by shutter speed.

Ambient exposure is affected by

aperture,
ISO
and shutter speed.

It's important to note that difference.

The implication is that if you shoot in one of these two Auto modes (Program, Aperture Priority), then your shutter speed could vary between shots.

eg, if you are photographing someone sitting close to a window with brighter light outside, then depending on your framing, your shutter speed will vary considerably. The only way to get a consistent look between your shots, is to fix the shutter speed (and aperture) - and this you can only do in manual metering mode.