Portrait photographers love fast lenses like the Canon 85 1.2 and Nikon or Zeiss lenses for the control over depth of field and the smooth out of focus blurring, or bokeh, that these lenses provide.
But, it's hard to justify the price tag for many of us. Photoshop users have been trying to simulate these effects for years – first with Gaussian Blur, and more recently Lens Blur. It works, but it isn't close to the real thing.
That's where Alien Skin's Bokeh (http://www.alienskin.com) comes in.
Bokeh is different because of the way it simulates different lenses to emulate their bokeh at various apertures. Along with realistic blurring from these lenses, you can also simulate various tilt-shift lenses, apply vignetting ala Holga or Lomo type cameras, and apply shapes to your out-of-focus highlights.
Ease of Use
The list of presets included with Bokeh is very impressive. There are various blur level presets for different lenses and aperture settings, along with vignettes. Of course, you can also customize any of these presets to fine-tune the effect for your needs. In Figure 2, I've applied a 50% blur with a vignette simulating the Canon EF 85 f1.2 II at f1.2. The blurring is startlingly realistic, and side-by-side I'd be very hard pressed to tell which was natural and which was done in Bokeh.
The easiest way to use Bokeh is to select the area to preserve, or to create a mask for the area you want to protect. In this example (Figure 3), I've selected Cyley to retain the details I want to keep in sharp focus – essentially, if it's not green, it isn't masked for this one.
With the selection made, choose Bokeh from the Filter menu. In Figure 4, the image shows the out of focus effect with the basic setting applied. I want to modify this to emulate the Canon 85 f1.2L II. To start, I've selected the preset for this lens with a 20% blur applied and the f1.2 aperture setting (Figure 5).
There isn't a huge difference between these two presets, and I want to have my out of focus areas even softer, so I selected the 50% blur with the same lens settings (Figure 6).
To fine-tune the effect, select the Bokeh tab. Here you'll be able to specify how the blur is applied to your image, as well as the Focus Region. For this particular image, the standard Selection type is what I want to use, but I can also apply either a Radial, for a rounded focus area, or a Planar for controlling where the blur begins and how far it extends before becoming full strength.
Other controls set the highlight enhancement and aperture diaphragm shape and blade curvature. The one control I find very interesting and useful here is the Creamy slider. Creamy adjusts how soft the shape of the aperture focus is. Figures 8 and 9 show the default of 0% and the less creamy effect with the control set to -50.