Learn how to use an external flash to improve your photography with this guide.
You may have just bought an external flash for your DSLR, or be considering buying one. They are a great addition to your camera kit, but do you know there is so much more you can do with it than just point it straight at your subject?
In this article, we’ll be looking at some of the ways you can use your flash creatively to give different lighting results.
A great way to get photos that don’t have that telltale dark shadow around your subject is to bounce the light from your flashgun off a white ceiling or wall. Point your bare flashgun head straight up at the ceiling in front of your subject. You can also point it up at a slight angle if you want to try a slightly different effect.
When you bounce your light off a large, white area, it becomes much softer and if you bounced off a ceiling, your subject becomes evenly lit from above. You can make your light more powerful by bouncing, as the whole ceiling effectively reflects light downwards. This means that the narrow light from your flash is spread and diffused further.
Always bounce your flash onto the direction you want your light to come from. You may need to fine-tune this by turning your flash head slightly one way or the other. You can bounce flash from the side, too. You just need to decide what light direction will work best.
Another trick that wedding photographers try in dark, large venues is to bounce the flash off a white or light-colored wall behind them. It sounds counter-intuitive, doesn’t it? If you’re interested in the science as to why this works to light up large areas of a room in front of the camera, feel free to Google it or look on blogs such as Strobist or Neil van Niekerk for an explanation. Neil’s blog Tangents has a wealth of free information on using bounced flash and other ways of using flash, and Strobist can take you from their free Lighting 101 series up to more advanced uses of flash.
It’s to do with the size of the wall making the area of the light far bigger for those of us who are more interested in results than technical theory. Just try it, and you’ll see if I’m right. Just make sure that if you do this in a crowded room you don’t blind people behind you with your flash. You can create a black foam flag to wrap around your flash to help avoid this issue – check out Neil van Niekerk again for the Black Foamie Thing!
One thing to be careful of when bouncing flash is the color of the walls or ceiling. If they are anything other than white or cream, you’re going to have some strange color casts to try and get rid of in post-processing.
Diffusing Your Flash
If you have nothing to bounce light off, or you’re outside in a wide-open space, consider using a diffuser or softbox on your flash. A diffuser is a white, opaque piece of soft plastic that fits on top of your bare flash head, completely covering the bulb. Most flashes have an inbuilt piece of flimsy plastic that flips down and is supposed to do the same job, but proper diffusers are much better and not expensive.
You can buy a whole range of lighting modifiers especially for flashguns, but probably the most useful of them for beginners is a softbox. These miniature versions of studio softboxes do the same thing; they soften and diffuse the harsh light coming from the bare flash bulbs, and you can control the direction of the light a bit more than you can with bouncing.
If you don’t have a softbox but you do have a 5-in-1 reflector and an assistant, get them to hold the central panel that’s covered in diffusion material in front of your flash. This is a quick fix, but will give good results.
Shooting in Harsh Sunlight
A great use for your flashgun is for shooting outside on bright, sunny days. If your subject is facing away from the sun and you shoot without flash, you’ll end up with a silhouette. Add a flashgun and diffuser pointed straight at your subject and they are as evenly lit as their surroundings.
Point your flashgun slightly to the side of them, and you will get some interesting shadows on their face, which can stop your image looking flat and boring. Using your flash on TTL (through the lens) mode is simple, as it changes its own power output depending on your shutter speed and aperture choices.
Mixing Flash and Ambient Light
This is sometimes referred to as ‘dragging the shutter’, and is something to learn more about when you are comfortable using your flash in all situations.
When you mix flash and ambient (background) light, you get some really great effects, depending on how much of each one you allow to register on your camera sensor. A balanced mix of flash and ambient will give a beautifully exposed subject and background, even in a dimly lit room. If you drop the amount of ambient light by a couple of stops and have more flash in the image, you get your well-lit subject with a slightly darker background.
The best way to work out your ambient and flash mix is to use a light meter to tell you the correct exposure for your ambient light at the aperture you want to use. You would then meter separately for your flash light until it was correctly exposed on your subject.
The ambient exposure shutter speed is the one you will use on your camera settings for a balanced exposure, if you want the darker, more dramatic background you would increase your shutter speed a couple of stops, say from 1/20th second to 1/40th or 1/80th second. This makes your background darker because you are allowing less ambient light in to the sensor, but your subject remains perfectly exposed because they are lit by the flash.
You need to be able to use your camera and flash on manual for this, so it’s something to try when you advance your skills.
Taking Your Flash Off-Camera
Flashguns are versatile because they can be removed from the top of your camera and moved around to give light from different directions. You will need something to trigger your flashgun, and the flash has to be in manual slave mode. You can add two or three flashguns on slave mode to really get some cool studio lighting effects, but I would master one light first before trying to add others.
You should give some serious thought to buying a flashgun, as they do open up new avenues of photography than if you just stick with natural light. I would suggest buying an inexpensive flashgun compatible with your camera first, to see if you like using them, as the brand name flashguns do tend to be several hundred dollars.
Are you a flash aficionado, or do you prefer sticking to natural light?