It’s easy to get shallow depth of field with a camera. You just need a camera with a large sensor, and a lens with a large maximum aperture and the laws of physics do the rest. But adding depth of field digitally is trickier, so let’s see if a filter designed specifically to do this job can produce genuinely realistic results.

The new Lens Blur filter in Perfect Effects 8 (part of the new Perfect Photo Suite 8 bundle) is going to look familiar to anyone who’s used past versions of Perfect Photo Suite. It’s actually the Focal Point 2 plug-in (or much of its functionality), but it’s been absorbed into Perfect Effects 8 and no longer exists as a standalone plug-in.

It produces three types of digital bokeh, so let’s look at each one it turn to see how effective it is – and how the digital version fares when reproducing optical depth of field effects.

Perfect Effects 8 Lens Blur filter

You need to start Photo Effects 8 and then ignore the presets sidebar on the left and go straight to the tools panel on the right. In the Filter Options panel, open the Filter menu and choose Lens Blur from the list…

01 Tilt Shift secrets

Perfect Effects 8 Lens Blur filter

The Filter Options panel has buttons for the three types of lens blur, and we’ll start with Tilt Shift (circled), since this creates a ‘miniature’ effect that’s very popular right now.

Focal Point 2 had a ‘FocusBug’ gadget which has been simplified in this new filter – here’s a guide to the different parts of this focus gadget and what they do:

  1. You drag this to move the whole focus gadget around the image.
  2. Drag this to rotate the gadget and change the angle of the plane of sharp focus.
  3. These solid inner lines indicate the outer edges of the areas which will remain in sharp focus.
  4. The gap between the inner lines and the dotted outer lines is the distance over which the defocus effect is blended in.

Digital tilt shift effects need the right kind of subject. This shot works because you’re looking down on the subject at an angle. The whole scene is on a single receding plane, and the blurring at the bottom of the picture and at the top is just what you’d expect from a tilt shift lens or a lens used at a wide maximum aperture.

This shallow depth of field tricks your brain into thinking it’s looking at a close-up of a model.

Perfect Effects 8 Lens Blur filter

But this picture doesn’t work so well. That’s because there are two planes of focus – one receding into the distance, but another vertical plane of focus created by the lighthouse tower. The simple compromise is to set the focus gadget so that the top of the tower stays in focus, but that means the sea beyond stays in sharp focus too far into the distance.

Perfect Effects 8 Lens Blur filter

The alternative is to set a shallower depth of field with the gadget and then use the Focus Brush tool to paint in the top of the tower to keep it sharp. This is slow and painstaking work, and even if you can paint right up to the edges, the white blur from the lighthouse still bleeds into the sea.

It’s not just Perfect Effects that has this limitation – it applies to any digital tilt-shift effects. Unless you really want to spend a lot of time with the manual masking, it’s best not to get too obsessed with precision and just go for settings that provide the broad ‘look’.