66 | PhotoPlus June 2014

Skills Exposure settings

Location and subject For our shoot we visited Cotswold Wildlife Park in Oxfordshire. Wildlife portraits are great for

demonstrating how the aperture affects depth of field; you’ll generally want a wide aperture, somewhere between f/2.8 and f/5.6, in order to capture a shallow depth of field that makes subjects stand out from surroundings that are often ‘busy’ and similar in colour.

Aperture Priority mode To get to grips with aperture without having to worry about the shutter speed, set your D-SLR

to Aperture Priority mode – Av on your camera’s mode dial. The great thing about Aperture Priority mode is that you can take full control of the aperture setting, and the camera will set an appropriate shutter speed to deliver a well-exposed image.

Aperture and depth of field To understand how aperture affects depth of field, start by selecting the widest aperture

available (the smallest f number). Take a shot, stop down to a medium aperture such as f/8 or f/11 and take another shot, then dial in a narrow setting such as f/22 and take another – you’ll see a big difference between the shots in terms of how much of the scene is in focus.

Shutter speed and ISO For optimum image quality set the ISO to 100. The camera will set the shutter speed, but if

you’re shooting handheld you’ll need to keep an eye on the shutter speed to ensure it’s fast enough to avoid camera shake and capture sharp shots. If your shots are coming out blurry, you can increase the ISO to get a faster shutter speed at a given aperture setting.

Clone out distractions Duplicate the ‘Background’ layer. The foliage in front of the red panda’s face is distracting, so take

the Spot Healing Brush tool and zoom in on this area. Tick Content Aware, and set the brush size to around 70 pixels. To clone out a long stalk, click at one end of it, then hold down Shift and click at the other end to clone out the whole stalk in one go.

F-stopsAperture values are measured in f-stops, also referred to as f-numbers; f/2.8, f/4, f/5.6, f/8, f/11, f/16, f/22 and so on. Moving from one f-stop to the next doubles or halves the amount of light entering your camera. Shutter speeds operate on the same principle, so if you narrow the aperture by one stop, you’ll need to slow the shutter speed by one stop, say from 1/100 sec to 1/50 sec, to record the same exposure. The amount of light entering the camera will be the same at 1/250 sec and f/5.6 as at 1/125 sec and f/8, for example.

‘Fast’ lensesYou’ll often see lenses referred to as ‘fast’ or ‘slow’. How fast a lens is depends on its maximum aperture setting, and a lens with a wide maximum aperture, such as f/1.4 or f/2, is called a fast lens because it enables you to capture a good exposure while using relatively fast shutter speeds to prevent camera shake, which is a benefit if you’re shooting handheld or in low lighting. Fast lenses also enable you to capture a shallower depth of field than standard lenses, so they’re popular for portrait photography.

Phrase Book

ACR adjustments Open the start image in ACR. On the Basic panel set Temperature to 4650 to warm up the image,

and set Exposure to +0.55 to brighten it. Set Shadows to +54 and Blacks to +43 to lighten the shadowed areas, and set Contrast to +9, Clarity to +23 and Vibrance to +38 to boost the contrast and colour. Click Open to open the image in Elements’ main editor.

PhotoPlus June 2014 | 67

Clone Stamp tool To remove the foliage obscuring the more detailed areas of the panda’s face select the Clone Stamp

tool. Make the brush a little bigger than the area you want to retouch, then Alt-click to sample ‘clean’ areas of fur, and click-and-drag to clone these over the foliage.

Dodge the shadows

Take the Crop tool, select Use Photo Ratio from the Crop menu, and crop in to remove some of

the foliage on the left and make the panda larger in the frame. To bring out more detail in the dark fur, select the Dodge tool. Set Range to Shadows and Exposure to 15%, and dodge the darkest shadows, then set Range to Midtones and dodge the lighter areas of shadow.

Add a vignette Next we’ll add a vignette to darken the corners of the image and help draw the eye to the subject.

Go to Filter > Correct Camera Distortion, set Vignette Amount to -43 and Midpoint to +35, and click OK to apply. Add a Levels adjustment layer, and set the Shadows slider to 9, Midtones to 1.04 and Highlights to 237 to boost the contrast.

Sharpen the shot

Add a Brightness/Contrast adjustment layer, and set both Brightness and Contrast to 6.

Next target the top layer, and press Ctrl+Alt+Shift+E to create a merged layer containing all the visible layer content and effects. Go to Enhance > Unsharp Mask, set Amount to 64%, Radius to 2 pixels and Threshold to 2, and click OK.

It’s not just the aperture

setting that affects the depth of field – the focal length of your lens also plays a role, with longer focal lengths producing a shallower depth of field. This is because, compared to short zoom settings, at longer focal lengths the frame will be filled with a smaller area of background, and so any background blur will be magnified too.

A combination of a wide

aperture and a long focal length will create a shallow depth of field that will knock the background out of focus, but you still need to think about the background, and how far your subject is from it. The further a subject is from its background the more you’ll blur the background, but unless you’re working with an obedient pet you can’t position animals exactly where you want them,so you’ll need to think about the angle and viewpoint you’re shooting from.

Super Tip!

Super Tip!

How aperture affects depth of field

Only the subject’s face is fully sharp – areas such as the rear legs are slightly out of focus

Wide

Next issue Master shutter speed for great action shots

Most of the scene is sharp, with only very near or distant areas noticeably out of focus

Narrow

Subject is sharp, and foreground and background areas are progressively defocused

Medium