Use Fill Flash for Better Outdoor Photos

When you think of using your flash, what “conditions” come to mind? Is it dark rooms and nighttime shots of people? Do you use your flash outside during the daytime? One of the best techniques you can learn to improve your shots is using fill flash.
For some outdoor photos, the subject is facing the light source (usually the sun) behind the photographer. In that situation, the subject is often lit well and fill-flash is not necessary. Earlier or later in the day usually works out well for this.

However, in the middle parts of the day, when the sun is directly overhead eyes will be partially in shadow and areas below the nose will be in shadow (or an entire side of the face). If your subject is wearing a hat, then the whole face might be in shadow.

Sometimes, even in earlier parts of the day, depending on subject placement you will still get unwanted shadows. Moving the subject for optimal light is not always an option. Considerations such as non-distracting backgrounds or a specific background you want to include for setting the surroundings will dictate the positioning of your subject. For stationary subjects you obviously will often not have a choice to place the subject elsewhere.

Fill flash is a technique used to lighten shadow areas outdoors. It can produce fantastic results by filling in shadows on faces, and balancing the light in the scene. It’s also used when the background is significantly brighter than the subject.

How to Set Your Camera
To use fill flash, the aperture and shutter speed are adjusted to correctly expose the background, and the flash is fired to lighten the foreground. You can use a speedlight in the hot shoe of your DSLR or the on-board flash.

Some speedlights have a balanced flash mode. For example, Nikon’s i-TTL (intelligent through-the-lens) Balanced Fill-Flash automatically balances the output of the Nikon Speedlight and the scene’s ambient light.

Most point and shoot cameras include a mode that forces the flash to fire, even in bright light.

Depending on how far your subject is, the flash will sometimes overexpose the subject, especially at close range. To overcome this, simply use the flash exposure compensation available on your DSLR. If you have a point and shoot, your camera may also have this mode, if not, use standard exposure compensation.

The opposite is also true, you may experience underexposure (particularly with a very bright background) so you may need to dial in some positive compensation.
There are a few different approaches for DSLR users; I generally use one of the following.
  • Semi-Auto Mode I set my camera to a semi-auto mode such as aperture priority and my speedlight to TTL-BL. I take a test shot then adjust the flash exposure compensation on the speedlight as needed. Note: If I’m using the on-board flash I’ll simply use the camera flash exposure compensation. Keep in mind, if you do have your speedlight in your hot shoe, for many cameras using flash comp on the camera and on the speedlight is additive. If you have +1.0 set on the camera, and +0.7 on the external flash, you will get +1.7 total compensation. I always use the compensation on the speedlight when it’s mounted so I only have one place to control the setting from. TIP: When using your on-board flash on your DSLR, depending on the lens and focal length you are using, your lens hood may cast a shadow on the lower part of your image. If that happens, you may need to remove it temporarily.
  • Expose for Background, Add Light Another method is to meter for the background and lock the exposure. Then recompose your shot and focus on your subject and add or subtract exposure compensation as needed. In some lighting situations where the background is very bright, it is helpful to under expose the background by one stop (-1.0) using exposure compensation or manual settings, then use flash compensation to achieve a properly exposed subject.
  • Slow-Rear Sync Sometimes I’ll combine the methods above and use slow-rear sync flash (camera in manual mode to control the background exposure) and I’ll manually adjust everything else, including flash compensation. This can be particularly useful for panning shots when the subject is at close range.

The key really is in using the flash exposure compensation and a good metering on the scene. With practice you’ll learn to use shutter speed, aperture, ISO and flash to gain maximum control.

Keep in Mind

Here are some things to keep in mind when using fill flash.
  • The closer your subject is, the easier it will be to overexpose them. This is why learning to adjust flash or exposure compensation on your camera is so important.
  • Know the range of your camera’s flash. Fill-flash won’t have any effect if the flash cannot reach them.
  • Know the sync-speed of your camera and speedlight. This is the maximum shutter speed your camera and speedlight can stay in sync, Some cameras have high-speed sync modes that can be used over the max sync speed (with compatible flashes). A topic for another time.
  • Even on overcast days when the sunlight is diffused, flash can be helpful to give your subject some “pop”.
  • Don’t overdo it! The idea is to subtly add enough flash to help eliminate shadows and balance the light in the scene. If you try to completely get rid of all the shadows your image may end up looking flat and have a “flash” look.
  • Try setting your white balance to auto or flash. I often set mine to flash, but do use auto sometimes.
  • Another advantage of fill-flash is it helps to highlight the eyes of your subject and provides a catch light adding life to otherwise dull eyes.
  • Where you meter the scene will have an impact on your settings. Especially for subjects that are constantly moving (toddlers, active kids, etc.) I often use matrix metering (some cameras call this evaluative or segment).However, I do use center-weighted or spot from time to time.
  • Practice! Anticipate ahead of time what you want to do and plan to take a few extra shots to try out different settings. Use the image display (and histogram and “blinkies” if your camera has them) to help you make adjustments as you go.
  • Through experience you will also learn when to use editing after the fact to make further adjustments. You might be asking why not just use the shadows and highlight tools all the time and not bother with flash? In my experience, you can sometimes do that, but often the results are not nearly as good as learning to properly adjust the flash on the front end, and use editing to make minor adjustments (verses major recoveries).
Flash Sync Speed (Section added 04/27/2010)
When using flash outside you may find yourself eventually bumping up against the camera’s flash sync speed. Essentially, over a certain shutter speed the camera is unable to properly sync the shutter and the flash. The results vary, and you can end up with odd results.

What to do

  • Look up your camera’s flash sync speed in your owner’s manual so you know what that speed is for your particular model of camera. 1/200 is common for on-board flashes. For point and shoot camera’s the mode you are in may limit the shutter speed automatically.
  • Keep an eye on your shutter speed so you know if the flash will sync properly or not.
  • If the scene is very bright (or background), you may get an overexposed image. You may have to increase your aperture to compensate. Some photographers choose to shoot in shutter priority and select the camera’s maximum sync speed and let the camera adjust the aperture as needed. Then, as mentioned before, adjust the flash compensation as needed to properly expose your subject.
  • Once you are starting to master using flash, you may feel more comfortable setting your camera to manual or using the exposure compensation (not to be confused with the flash compensation) to greater control the outcome.
  • If your camera is trying to use shutter speeds in the 1/1000 range, you will need to increase the aperture to get that speed down to sync with the flash, or decrease your ISO (if you haven’t already). You can use any mode you wish to change the controls to accomplish getting the shutter speed within the desired range (aperture or shutter priority, or manual mode). If you have a speed light (external flash unit), read on…

If you have a speedlight
Some models of cameras and compatible speedlights will allow you to shoot effectively with flash at much faster shutter speeds. This is accomplished by the flash unit delivering several smaller bursts of light instead of one large burst. The downside is that the flash is of less effective intensity since the individual bursts are lower powered than the normal capability of the flash unit.

Cameras and speedlights that allow high speed sync will have a section in their manual instructing you how to set your equipment up to take advantage of the feature.

Example Scene

Preparing for this article my daughter posed on our deck for me. Notice the harsh shadows without the flash. These pictures were taken at 7:15am. with my camera in aperture priority. The images are marked where I used a speedlight (in balanced, TTL-BL mode), or on-board flash (lens hood removed) and what flash compensation I used (if any).

This was not a perfectly controlled test, but it should give you an idea of the possibilities of fill-flash.

No Flash
   
Speedlight
On-Board Flash

    
What fill flash tips do you have?
How has fill flash improved your results?
   
      

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6 Responses to Use Fill Flash for Better Outdoor Photos

  1. Sarah says:

    Yes, this was exactly what I was looking for! Thank you so very much for taking all the time to write this information. I've read several posts in your blog just since last night, and feel like I can test and try new things simply by following your directions. It's great! McMommy/Sarah from TPF

  2. Sarah- I'm so glad you're finding the articles here useful!

  3. Lovebugs says:

    So when you are exposing for the background, do you set the focus point to the background, set the exposure, and then set the focus back on your subject; or actually slightly move the camera, set the exposure, and then move the camera and focus back to your subject?I'm just thinking of how much "work" this would be to do chasing a toddler. Does it just get easier with feel, time, and practice?Sarah

  4. Sarah- It does get easier with time and practice and you will get a feel for it. There are times it's easy to get frustrated (I've had my fair share of those moments, and still do from time to time). Especially when you want nothing more than great shots of your kiddos.So, yes. You aim your focus point to the background to set exposure, then recompose with the focus point on your subject and focus on the subject.When aiming at the background, you will want to actually "lock" your exposure, or go to manual mode and dial in the exposure using the exposure indicator bar in your viewfinder. I usually use aperture priority, and use the "AE-L" (exposure lock) feature on my camera. That way I can easily dial in exposure compensation + or – from there. So my suggestion is to plan a time when you can learn to use Exposure lock or set the exposure manually and this whole process will be less stressful when trying to get a picture of a moving toddler (been there) and now that my kids are 4 and 7 (daughter just turned 4 today!) it doesn't get any easier.I hope that explains it. Keep asking questions if you need to!

  5. Sarah (and all)- I will be adding to this article about your camera's flash sync speed. Bascially, on most cameras, over 1/200 with the on-board the flash may not sync. So something to watch is that you set your camera to be within the sync speed for the flash. I will explain this more by adding to this article and sending a notice when I do so subscribers konw it's there. If you have a speedlight you have more options. More to come, sorry I don't have time to get into the details at the moment.

  6. Section added above for flash-sync.

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