Tilt-shift lenses are often used for architecture and product photography. The “correct” way to use a tilt-shift lens is to adjust the lens elements in order to minimize distortion or to shift the plane of focus for massive depth of field. But breaking the rules with a tilt-shift lens is a great way to create funky shallow focus effects. Here’s how.
WHAT TO USE, AND HOW TO DO IT
Canon makes a 17mm TS-E, a 24mm TS-E, a 45mm TS-E and a 90mm TS-E. Nikon (which calls these lenses “perspective control”) offers a PC-E 24mm, a PC-E 45mm and a PC-E 85mm. Lensbaby also makes a variety of tilt-shift and perspective-adjusting lenses, which work similarly, depending on which model you use.
Whichever focal length you choose, the functionality remains the same. These manual-focus lenses feature knobs and locks that can slide the lens up and down or side to side, or tilt the lens up or down. It’s the tilt that creates an altered plane of focus.
Simply tilt the lens and look through the viewfinder, and you’ll see that the plane of focus has shifted. It’s normally parallel with the lens plane and the sensor plane, but once the lens plane tilts, the focus plane tilts, as well. In practice, it means a standing subject’s face might be in focus, but his or her feet are blurry.
To employ the effect, all you really have to do is attach the lens, open the aperture wide, dial in a tilt and shoot away. TS and PC lenses can only tilt in one axis at a time, but rotating the lens will shift that axis from horizontal to vertical if you want to change the orientation of the plane of focus.
The stronger the tilt, the more dramatic the focus shift. That said, at the extremes, image quality can suffer, and it can be difficult to expose correctly and focus accurately. Your focus indicator might steer you wrong, and auto-exposure controls surely will be off. I prefer to shoot manual and check the LCD.
One of the most popular special effects with a tilt-shift lens is called miniaturization. It’s when the shallow depth of field makes a normal-sized streetscape look like a miniature model. If you’re shooting with a wide-angle lens from a high vantage point, you’re in the ideal position to create a look that makes a normal street appear miniature.
I’m of the belief that nothing looks quite like a real tilt-shift lens. But I also know there are lots of great ways to approximate tilt-shift shallow depth of field with a computer. I like one approach with Photoshop and another one in Lightroom.
Lightroom’s Develop module contains some really powerful tools for selectively modifying a scene. You may be tempted to reach for the Radial Filter to draw a circle around the subject, but the problem with this approach is that a circle of sharpness looks nothing like the way an actual lens creates a plane of focus that cuts through a scene. So to better approximate the effect of an actual tilt-shift lens, we’re going to rely on the Graduated Filter. It’s found right up at the top of the Develop panel, just beneath the histogram. When you click it, a dropdown panel of sliders will emerge. The only one you want to use for this is the Sharpness slider. Don’t drop the Clarity; in my experience, it muddies the effect.
Next, drag the Sharpness slider all the way to -100. Then click and drag from one edge of the frame toward the center of interest. You’ll see the blur appear as you drag; let go when you reach the subject. If the effect isn’t strong enough, click New for a new graduated mask, and click and drag over the first gradient. This effectively doubles the intensity of the blur.
If, at any point, you get a little too heavy-handed and blur more of your subject than you want, click Brush just below the Graduated Filter header to activate a brush that can add or subtract from the gradient mask you’ve just created. With the Brush active, simply hold the Alt or Option key to set the brush to Erase (or click Erase in the bottom of the dropdown panel) to paint away the blur that has spilled over onto your subject. This way, you can maintain the realism of a graduated blur without completely sacrificing the precision of a paintbrush approach.
Next, repeat the process from the opposite side of the frame, roughly 180º from the first filter, building up the effect with multiple passes, as needed. It’s the resulting sliver of focus between the two gradients that mimics the actual optical effect.
In Photoshop, starting with a normal image, duplicate the background onto a new layer and name it something like “Blurred.” Then use Gaussian Blur (in the Filter > Blur menu) to obliterate the detail from this layer. You want it blurry enough that you can’t see details, but not so blurry that you can’t see shapes.
Next type Q to enter Quick Mask mode, and choose the Gradient tool (hidden under the Paint Bucket) and a Reflected Gradient pattern from the toolbar. This will allow you to click and drag a gradient that will go from 0% up to 100% and back down to 0%, all within the space of the line you drag. It’s a one-step solution for creating a selection that eventually will become the swath of sharpness through the frame. Type Q again to exit Quick Mask mode, then click the New Mask icon at the bottom of the Layers palette to turn this gradient selection into a mask, revealing the sharp original layer through the blurry top layer.
If your band of sharpness isn’t just right, add or subtract with a brush set to 50% opacity and paint directly on the mask. With the mask active (click on the mask itself in the Layers palette), you can use a black brush to reveal the sharp layer below or use a white brush to hide the layer below and add to the blur. This way, you can subtly expand the area in focus to include eyes, hair, clothing or anything you want to be sure it reads clearly. Alternately, it can be used to hide otherwise sharp details that you’re not particularly interested in seeing.
Ultimately, tilt-shift lenses are a fun way to provide some amazing shallow focus effects. But if you can’t get your hands on one, or you’d simply like to approximate the look on an existing image, Lightroom and Photoshop offer straightforward and powerful tools for faking funky focus.