Caption: Flash is used outside to create motion yet freeze the subject.

To flash or not to flash, that is the question – at least for this article. There are two primary issues, the yin, and yang, of answering this question – the Technical and the Aesthetic.

Sometimes there isn’t enough light to make a picture, and you need to use flash. At other times the use of flash is unnecessary but can improve a photo.

There are a lot of situations that, even from a purely technical standpoint, are borderline and hard to call. Here it is necessary to consider the end use of the picture. If the photo is for a computer screen, poor light is not so important because the light passes through the image. On the other hand, if printing in black and white in a newspaper or if printing on plain paper, flash can be a lifesaver. The newsprint isn’t a bright paper, and the ink is absorbed into the paper so much that what looks a little dark on a computer screen will be solid black in a newspaper.

When photographing people with extremely dark skin tones, the flash will open up shadows and give modeling and definition to the face.

Picture (if you will) a shaft of light streaming through a window onto someone’s hair, creating a halo effect. Even though the face isn’t all that distinguishable, using flash here will destroy the mode. Sometimes the aesthetic rules over a technically correct rendition.

Another aesthetic reason is not to use a flash once you fire a flash; people are aware pictures are being made, and their expressions may change from natural to posed. So you may get one realistic shot, but you’ll rarely get others.

Here again, it can be hard to decide what to do. If you take photos of people without a flash and the expression is just right, even if the light is poor, it is often better than a well-lit but posed shot. However, a flash is called for if you can’t see the expressions or if the image will be in a newspaper and their faces lose too much due to the printing process.

Not sure of the use? Want to be able to use the photo in many ways? Then it would help if you were sure the quality would work anywhere it might appear.

You will need a high ISO (800 or 1600) if you use available light, but the photo may be pixilated. On the other hand, if printing the image large for use in a display booth or a slick magazine, you need to shoot at a lower ISO and use a flash.

Photography is always a trade-off, a compromise.

At times flash is not permitted. For example, museums often don’t allow flash since it can fade the colors in prints or fabrics.

Surprisingly, the rule of thumb most people apply to the use of flash is the reverse of what it should be. They don’t use the flash outside when it would help open up shadows; they use it inside where it can destroy mode and restrain naturalness.

By reversing the standard rule of thumb and using flash outside, not inside, you discover a new way of seeing the light.

With digital, seeing the results is immediate, So why not shoot these tough choices both ways and compare the outcome?

If people in your pictures appear possessed by an evil being (and you’re sure they are not), the problem is the Dreaded Red Eye.

We have all seen the horrible red eye, but how do you avoid it? What causes it?

On-camera flash is the culprit.

When the flash is so close to the camera lens, the angle formed by the flash to the eye and back to the lens is so narrow the sudden bright light bounces off the retina and back into the camera lens.

The eye’s iris is open relatively wide before the sudden flash, and what you see the red reflects the light of the blood vessels in the retina. No wonder it is called the dreaded red eye.

Since the problem is the narrow angle between the flash and lens combined with a wide open iris, we must either move the flash or “stop down” the eye or both.

Changing the Angle

Many digital cameras have a flash built into the camera right next to the lens. Convenient, but it can cause red-eye problems. Some of these same cameras also have a hot shoe allowing you to use an external flash far enough from the lens to reduce the likelihood of red eye.

If you use an extension flash cord (PC cord), you can raise the flash further above the lens, not only avoiding red eye but also casting the shadows down behind the subject and not on the wall behind your subject. Ever been to a wedding and watched the photographer; that’s why she got her flash stuck way up in the air in her head.

Another way to increase the angle bounce the flash. Use a flash with a tilting head to reflect the light off of the ceiling. Don’t try this where the ceiling is very high, like in a church or outside, unless the low-lying clouds are extremely low (just kidding).

Other Ways To Solve The Problem

Some cameras have what they call a red-eye reduction feature. The camera fires a burst of flashes before the actual flash. This burst of bright light causes the eye to “stop down” and, theoretically, is irritating and causes blinks. Well, that would get rid of the red eye. Better than flashing at your subject to get their eyes to stop down, have them glance at a lamp in the room or, if it is daytime, glance at a window.

Do you need a flash? Sure, you will have to use it sometimes, but can you turn on more lights in the room and get the light bright enough for photography? Maybe move your subject close to a window. Perhaps you can raise the ISO, say from 200 to 400.

The “available light” photos can be beautiful and move your photography to a new level if done correctly. Why not take the person outside in what Kodak likes to call “open shade” in the shadow of the house, for instance?

Oops! Too late. The people have left, and NOW you notice the dreaded red eye. All is not lost. There is probably some software that comes with your camera that lets you fix the red eye on the computer. Since there are so many different software solutions, you will need to refer to your manual for this fix.

I like to check before taking photos to see if there is enough light to work without a flash or if I can make it that way. Firing a flash announces that someone is taking pictures of people as they are.

Sometimes you have to use flash, but now we know how to avoid some of the problems it causes.

Happy shooting!