Shedding Light on Using Flash In Your Photos

There truly is more to flash photography that meets the eye. During the first few years of owning my DSLR camera, I used the automatic mode almost exclusively. I noticed that the flash went off frequently in a variety of settings, but I never gave much thought to when it should really be used until now. Since this is a tutorial for the amateur photographer, I'll discuss the basics that will get you started using flash more purposefully and efficiently.




How is flash defined?
Flash is a light source that produces a flash of artificial light with the purpose of lighting a dark scene. Ok, that was easy! So what's next?

A few things you should know about flash photography...
Although flash is a very useful tool in photography, it can have a negative effect on your subject. The following are a few problems you may encounter as well as tips on how to fix them.


Red-eye: Have you ever wondered why this happens? Well, the answer is very simple. When flash is used in a poorly lit setting like a restaurant or outdoors at night, the light from the flash reflects off the retina of the eye. The retina is made up of many tiny blood vessels, so the red that we sometimes see in our photos comes from the blood in the tissues of the retina. Mystery solved!

Example of red-eye - scary huh!
Photo courtesy of Wikipedia

The fix: Red-eye is unflattering in a photo and to be honest kinda scary looking! The good news is that there's a way to prevent red eye from occurring before the photo is taken and ways to to fix it afterwards if you didn't notice it when taking the photo. Let's find out how.

• DSLR camera's have a feature called red-eye reduction which causes the flash to go off before the picture is taken and another flash when the shutter release button has been fully pressed. Bear in mind that your subject has to be looking directly into the camera in order to use this setting. If your camera doesn't have this feature or if you don't want to change your flash setting, you could take two pictures. This will produce the same effect because the first flash will contract the pupil of the eye, minimizing if not ridding the shot of the dreaded red-eye effect.
• Turn on the lights! Stand near a light source (lamp) or brighten the room with more light if possible. The additional light in the room will make the pupil of the eyes smaller, again reducing the effect of the flash.
• Another reason why red-eye occurs is the result of your camera's built in flash being too close to the lens. I know, I know, that's not your fault! Here's the solution...a detachable digital flash (like the one below) that fits above your camera's built in flash. It can be used to "bounce" the flash off a surface like a wall or ceiling instead of pointing it directly at your subject. A very useful site to visit with more on this subject is found here: http://www.digicamguides.com/accessorize/external-flash.html. 




Portable flash
Image courtesy of Wikipedia

• If you have already taken photos and your subjects are sporting the red-eye look, you can always use photo editing software to correct it. There are many software choices out there, but I would highly recommend Google's awesome free photo editing software Picasa 3.8. You can download the software at: http://picasa.google.com/mac/. It is super easy to maneuver your way around this software and you'll love the cool added features. You may also want to try http://www.gimp.org/ which can also be downloaded for free. It has features similar to Photoshop and can be a bit of a challenge to work with at first, but if you have some time to devote to it, it is a great software to use to edit your photos. Give them a try!

Overexposed photo: Another problem the use of flash presents is a photo that looks harsh with washed out colors and a hard shadow.

Harsh, washed out effect of using direct flash due to overexposure

Properly exposed photo

The Fix: You can choose to decrease the flash power by using flash compensation, a feature present in many of today's DSLR cameras. Flash compensation allows you to increase or decrease your camera's flash intensity and helps guard against over and under exposing a subject.

Another great tip is to use a home-made diffuser to soften the flash output. A diffuser is used to disperse light or soften it. All you'll need is a piece of white tissue or white paper (tracing paper is also a good option) and a bit of tape to attach the paper or tissue to the front of the flash. Remember that whatever you decide to use, make sure to choose white or your photo will pick up the tint of any other color you use. This also applies to walls, if you are bouncing your flash off a wall or ceiling, make sure the walls are white or your photos will have a tint that resembles the color of the wall or ceiling. Placing a mirror at a 45 degree angle facing the flash is another great tip. Use this to create a greater fill light effect in your photo.
These home made alternatives work well, but if you would prefer to have what the professional photographers use, then there are many flash diffusers to choose from that are quite affordable.

Hard flash 

Result of using white paper to diffuse the flash

Yellow paper was use to diffuse the flash...notice the yellow tint (How can you miss it?) 

Here I used a mirror to bounce the flash. The walls are ecru...the mirror reflected that color onto the photo.

Photo was captured using tissue to diffuse the flash

Reflectors are also something you may want to consider. Reflectors redirect light onto your subject. The home-made version is to use white foam core (found in any craft store). You can use it to direct light onto your subject. The reflectors used by photographers are circular discs that are again an inexpensive option. They come in a variety of colors...white, black, silver and gold, each with a specific purpose. I will discuss more about this in a post dedicated to camera accessories that are a must have for the amateur photographer. Until then, if you would like to see images of the different diffusers available or more information about diffusers and reflectors take a peek at this site: http://www.digital-slr-guide.com/flash-diffusers-and-reflectors.html.

A few more flash photography tips:
Your camera's built in flash is not powerful enough to impact subjects that are out of its flash range. If you are considering getting into professional photography, the portable flash is a must have.

It's important to keep in mind that aperture affects the exposure of your photos. When using flash, set your camera to an aperture of f/5.6 (wide opening), a smaller opening like f/22 for example allows only a small amount of light into the camera's sensor. Your camera's built in
             flash is not powerful enough to illuminate your subject with an aperture of that size.

The higher your ISO, the greater the power of your flash. When shooting under low light conditions, bump up your ISO to raise your flash exposure.


But what about all those different camera options for flash? 
This feature varies depending on the camera. I'll end this segment with the functions of each and when they are best used.
Automatic - In this mode, the camera detects low light levels and automatically fires the flash.
Flash on - Here the flash fires even with adequate available light. Use this setting when outdoors.
Flash off - Use flash off when you are somewhere where flash is not allowed.
Slow sync - Flash is accompanied by slow shutter speeds to balance light between background and subject. This setting is great for night time or when shooting indoors.
Fill in flash - In this setting, the flash is less powerful that the regular flash, but is capable to add fill light to dark areas/shadows. Use when you need to illuminate your subject but not the background.
Flash w/ red-eye - This setting should be used when indoors or when in low light environment. It reduces the appearance of red-eye.
Rear sync mode - A neat feature to try out. Rear sync mode freezes your moving subject giving them a slightly blurred effect.

Whew! That was a lot to digest! The area of flash photography is so very extensive and can be very technical as well. I wanted to bring to you key points that I found helpful when researching flash and how to use it effectively. Hope this has helped you!