Fill Flash Photography: How to Get Beautiful Portraits (Even in Bad Light)

What is fill flash photography, and how can you use fill flash for beautiful portraits?

As a longtime user of flash, I’m familiar with all the standard struggles (in fact, when I first purchased a Nikon speedlight, I was very scared). But over time, I became a confident user of fill flash, and you can, too.

In this article, I’m going to tell you everything you need to know to get you started with fill flash. First, I’ll explain what fill flash actually is and why it’s important. Then I’ll go on to give some tips that’ll make your flash look as good as possible. Along the way, I’ll share a few simple tricks for getting creative results with just one flash.

Let’s get started.

What is fill flash?

Fill flash in photography refers to the technique of filling in shadows with artificial light, such as a speedlight or a strobe.

Generally, fill flash is used in situations when your subject is either:

1. Positioned in front of a brighter background
2. Covered by harsh shadows (such as under the eyes and chin in portraiture)

Fill flash acts as a supporting light, one that pops a bit of brightness back into those too-dark areas. It lets you get a shot that is well exposed in the background and the foreground (as opposed to a foreground silhouette or a bright-white background).

Fill flash is especially useful on sunny days, when the harsh overhead light beats down on your subject and casts lots of unwanted shadows. But you can also use fill flash when the sun is low in the sky and your subject is backlit, or when your subject is in the shade and the background is bright, or a number of other times when you have a dark subject on a bright background.

Make sense?

The basics of flash exposure

As photographers, we have to learn a host of technical knowledge. That involves a lot of trial and error to find which methods work for you. It’s no different when it comes to camera settings and flash power.

Normally, you must balance the three factors in the exposure triangle to achieve your intended look. For example, if you want a darker background with less ambient light, you can increase your shutter speed while keeping the aperture and ISO the same. But if you want ambient light in the background plus brighter shadows, you can lower your shutter speed while maintaining the aperture.

Adding the flash power as a 4th factor is no different. You simply have four variables to contend with rather than three.

So when you bring fill flash into the equation, you have the option of adjusting its power to brighten or darken the image. Or you can leave the flash power as a constant, then adjust the rest of the exposure variables to achieve the look you’re after.

As long as you have ample understanding of the basics of exposure, you’ll do just fine. Simply play around and find what works best for you; you want an approach that will make you efficient while also staying consistent with your workflow and style.

Now that you’re familiar with the basics of fill flash photography, let’s take a look at some tips for actually improving your flash results:

1. Put a diffuser on the flash

It may only be a little plastic thing that goes on top of the flash head, but I find that a diffuser does make a difference. 

With a diffuser, the light is less harsh. I know many will disagree about whether it actually softens the light, but I notice a softness from a diffused flash compared to a bare one.

2. Control the flash manually

When using flash, there are two common ways of determining the right exposure:

Exposing manually, or exposing with ETTL/TTL metering.

And I highly recommend you just do it manually.

Now, I know there are many big fans of ETTL/TTL mode out there. I have tried it, too. However, I have gone back to manual exposure as I find that TTL metering does not give me the look I want.

So set your flash to Manual mode and choose the power. I usually dial in 1/32 or 1/16 and leave it there. Adjust the flash power only when absolutely necessary. For basic exposure changes, just adjust your standard camera settings.

What I’m after is always a natural look which, depending on where the main light is coming from, may not be achieved without some kind of fill or reflected light to illuminate too-dark areas.

But I don’t just point my flash directly at my subject and fire wildly. Instead, I either bounce or angle my flash, as I explain in the next section:

3. Bounce the flash

On some speedlight models, there is a little white pull-out bounce card that is extremely useful if your ceilings are too high for the light to bounce off or you just want to point reflected light in a particular direction.

When I shoot weddings where the rooms have very dark or high ceilings, I pull out the bounce card and use it to deflect the light coming from the flash. I then swivel the flash to direct the reflected light wherever I want it to go.

As an aside, I use this setup for both on-camera flash and off-camera flash. When I’m putting two speedlights opposite each other to provide directional light during speeches, I point the flash heads upward and pull out the diffuser so that all the reflected light is pointed toward the center of the room.

4. Angle the flash

The head of most speedlights can swivel right and left up to 90 degrees and forward and upward 90 degrees in incremental angles. It is an awesome function that you should take advantage of – especially when using fill flash.

In the photos below, bright sunlight was coming from camera right at 45 degrees on a bright day. All I wanted was a bit of fill flash on their faces, just enough to lift the shadows a tad. And I didn’t want the image to look like there was another light source other than the sun. To achieve this, I angled my speedlight upward by one increment.

5. Experiment with power and angle

As you can see, the photos below have powerful sunlight coming directly at the subjects and toward the camera – a very strong backlight. It is extremely difficult to overpower this type of light without using a strong fill flash. 

So I angled myself slightly to one side and pointed my flash directly at the subjects’ faces to try and counteract the sunlight.

In situations like these, I increase my flash power accordingly. The result is not as clean and sharp as if I had a big softbox, but it still shows the faces clearly enough and I got some diffused, hazy light in the background, which was also my intention for these shots.

Compare the two images below. The one on the left was taken in a big open space with a dense foliage background. There was enough natural light to illuminate my subjects’ faces, but I pointed the flash backward to add just a tiny bit of light over my head. I don’t think it made a huge difference, but it made me feel better and more consistent!

The image on the right was taken in an open, shaded area surrounded by tall trees that diffused the light coming from the background. Without the trees, I would’ve had unfiltered backlight (as in the photos above). With the trees, the backlight was filtered but still present.

In other words: More fill light was needed! I pointed the speedlight slightly upward so it was aimed toward the subjects but not directly at their faces.

You can see the same flash angle as above on these close-up portraits:

6. Don’t overdo the fill flash (it’s okay to make things moody!)

While I was shooting the couple featured above, I wanted a look that was a little moodier. So I pointed the speedlight directly upward. 

Although the fill flash ensured their faces remained well-lit, the couple appears enveloped by the diffused light behind them:

7. Don’t be afraid to underexpose the subject

Take a look at the top image:

Notice how the couple is pretty dark, while the background is well exposed? The couple wanted a shot showing the lake and the trees in the far distance. But the distance was too great to get the couple and the background sharp and well exposed without using a really small aperture and a lot of artificial light (flash).

So I took two shots.

The first one is of the couple looking toward the trees. Everything is sharp, but the couple is clearly underexposed. I pointed the speedlight slightly forward to give them just a hint of light and shot with a small aperture.

The second image has the same angle of flash – but I got closer, and I changed my camera settings to a wider aperture. The background is now blurry while the couple is in focus.

For this ring shot, we sat on a bench with the sunlight coming from camera left. I put the ring on my phone to get a dark background and a nice reflection. With ring shots, I always stop down to at least f/7.1 with a macro lens. I also always use a speedlight pointed directly opposite the main light. So in this case, I swiveled my flash head to create a bit of reflected light on the right side of the ring.

Likewise, for the photo below, you can clearly see where the sunlight is coming from. I pointed my speedlight slightly upward to camera left, opposite the sunlight. This angle helped me achieve a gradual transition of light, as opposed to a dramatic decrease where you could see a clear cutoff from light to dark.

Your turn to try doing fill flash photography

If you haven’t tried using flash like this, I encourage you to do so. Experiment. See how it works for you! Sometimes all you need is confidence, common sense, and a willingness to try.

And if you’re successful, share your fill flash images in the comments below! We’d love to see them!