Canon DSLR tutorial: How to use fill in flash
Taking portraits in bright sunlight is always a challenge, but your camera’s pop-up flash can be used as ‘fill in flash’ to fill in the shadows. But bear in mind that the pop-up flash is only effective if you are within a few feet of your subject. To get a natural look you need to balance the power of the flash with the ambient light. In Program (P) mode, your camera will take everything into account and try to come up with the best balance but, as with anything artificially intelligent, there’s usually room for improvement.
The pop-up flash will only illuminate the foreground, but you can use your DSLR’s main Exposure Compensation control to lighten or darken the background, reviewing the effect on the LCD. Once you’re happy with the background brightness, adjust the Flash Exposure Compensation between +/- two stops in 1/3-stop increments, which gives you a fine degree of control over the balance between the flash illuminated and non-flash illuminated areas of the shot.
For a more creative effect, try switching to Aperture Priority (Av) mode. You can adjust the aperture as required and the shutter speed will change automatically to suit the ambient lighting conditions. Longer shutter speeds will be selected as necessary for smaller apertures or darker surroundings, with the added bonus of blurring background movement. Meanwhile, the main foreground subject can be kept sharp by the very short duration of the flash. Watch out for large apertures (such as f/4) in bright conditions as there is a danger the background will be overexposed, as the top shutter speed your EOS can use with flash is 1/200 sec or 1/250 sec (depending on the model). If this proves a problem the shutter speed will flash in the viewfinder – and you then need to lower the ISO or set a narrower aperture until the shutter speed readout stops flashing.
For ultimate creative control, switch to Manual mode (M) and adjust the aperture and shutter speed to expose the background correctly, using your camera’s built-in metering system as a guide. You can then adjust the Flash Exposure Compensation if necessary. Bear in mind that a good flashgun, such as the Canon Speedlite 430 EX, not only boasts a more powerful flash, but also makes it much easier to adjust the Flash Exposure Compensation via dedicated buttons on the back. See below for more flash tips…
1. Exposure Compensation
Press the Flash button on top of your SLR to pop the in-built flash up, then take a test shot and review the results on your camera’s rear LCD. If the background looks too dark or too light, press the Av+/- button on the back of the camera and use the main dial behind the shutter release to add positive or negative Exposure Compensation as required.
2. Flash Exposure Compensation
Now turn your attention to the foreground subject. Review a test shot on the camera’s rear LCD, but this time check to see if the flash-lit area is too dark or too bright. If necessary, adjust the Flash Exposure Compensation. On some models, press the Menu button and navigate to the second red Shooting menu to find this. On others there is a separate button.
3. Av mode
In Program mode, the minimum shutter speed available is 1/60 sec. Switch to Av mode and the shutter speed will be automatically adjusted for any given ambient lighting conditions to suit the aperture you select. Long shutter speeds are set for a ‘slow-sync’ effect in low light, but check that the shutter speed is not flashing in the viewfinder in brighter light.
4. Manual mode
Manual mode allows you to get creative. Point your SLR at the object you want to take a meter reading from and adjust the aperture and shutter speed, using the exposure scale on the LCD or in the viewfinder as a guide. This will lock the exposure onto your chosen value, enabling subsequent adjustment of Flash Exposure Compensation, as in step 2.
This entry was posted on Friday, August 23rd, 2013 at 10:31 am and is filed under Canon D-SLR Skills, Photography Tutorials. You can follow any responses to this entry through the RSS 2.0 feed. You can skip to the end and leave a comment. Pinging is currently not allowed.