Fill flash on the trail.

Paul during a hike at Minnekhada.  Left no flash, right fill flash added.

I have spoken about the benefits of fill flash before, but its value is so often forgone that it is well worth repeating.  Flash can make an enormous difference in many situations, even if the camera isn't suggesting its use.  In full auto mode, the camera will often pop the flash up when a low light situation is detected.  In other modes you may see a sign inside the viewfinder or on the LCD screen indicating that flash is warranted.  In automatic modes the flash is directly controlled by the camera and often cannot be suppressed or raised in contrary situations.  This is one of the reasons I so strongly suggest learning to use semi-automatic modes like aperture or shutter priority.  I often use manual mode as it provides even more control.

The trick with using flash though is very much dependent on the nature of the existing lighting, the camera, and the settings it is at.  It can be all very technical, but we can look at this from a more simplified perspective.  Shaded areas (such as the situation above), open areas on cloudy days, and indoors are all times when using your built-in flash can make a difference.  Brighter environments often benefit from a more powerful external flash, especially in cameras with a flash synch speed.

The second thing is to be closer to your subject rather than farther away.  Generally, this means keeping focal lengths.  A wide angle or mild telephoto setting will work better than zooming in more because it allows lower apertures to be used and deeps the flash-to-subject distance within the working distance of the flash.

Keep the aperture low.  Smaller apertures means the flash has to work harder; since built-in flashes have a relatively low amount of power ("brightness"), the lower the aperture number the easier it is for the flash to light something up.

Increasing ISO can improve flash distance, but it will only work with electronic shutter cameras, especially in bright situations.  In dim circumstances, a higher ISO will always allow your flash to go further.  As it gets brighter, especially with mechanical shutter cameras (DSLRs), increasing ISO has no effect.  An external flash is the only way to go in these cases.

Using a flash to fill a scene is easy.  Pop the flash up and take a picture.  If the flash won't come up, you will have to switch to a mode where it is allowed.  Portrait mode often works.  I will often take two pictures as you see above.  One with flash and one without.  Sometimes the flash makes no difference - so what is there to lose?  Other times though it makes a huge difference.  Aren't you glad you tried?

Thanks for reading.   www.ericspix.com