Nd filters with flash
Both blur and darken backgrounds to capture more dramatic portraits all by using a combination of filters and flash as peter travers explains
What’s the best way to shoot portraits in daylight? Use a long focal length and wide aperture to blur the backgrounds so the subject stands out? Or use some fill flash and underexpose the background for extra contrast and drama?
If you use a wide aperture for a shallow depth of field to blur the background behind your subject in even lighting, you may have to accept annoying shadows on their faces, and the backdrop will be much the same brightness as your subject as well (see right).
If you use flash you can fill in shadows on faces. But with your camera’s maximum flash sync speed of around 1/200 sec, you’ll need to shoot at an aperture of around f/9 or more if you want to underexpose and darken the background in broad daylight. At that aperture the depth of field increases, so this means the background isn’t that blurred, and your subject doesn’t stand out as well (see right).
But what if we could combine a wide aperture and flash to capture both a dark and blurred background? Well, by using an ND filter on our lens, we can!
With a neutral density filter attached to our fast 24-70mm lens, on our overcast day we could we can shoot at f/2.8 and 1/100 sec to blur the background and to darken it too. Plus by using a flashgun to brighten up our subject, it will separate them from the background, creating a really dramatic and dark portrait – a popular look with gritty TV shows and films these days.
Read on to learn the essential set-up and tips for a great shot.