Two Potential Solutions for Shallow Depth of Field with Digital Compacts

Unlike film compacts, current digital compacts are unable to achieve a shallow depth of field, with the exceptions being telephoto and very close range photography. In part, this limitation has to do with the fact that digital sensors achieve best performance when incident light hits the sensor "straight on." The inherently deep DOF of small sensor compact cameras is considered by some to be a strength of the format. The Small Sensor Cameras forum at GetDPI.com is a great place for discussion of how to make the most of this class of camera. However many, myself included, would like to see the development of compact digital cameras capable of shallow DOF. The DP1 is a step in the right direction, with greater potential for shallow DOF than any other digital compact camera with a similarly wide angle field of view. However, even the DP1 is stuck with a deep DOF by film compact standards. The wonderful examples of shallow DOF shown by Carl Rytterfalk and others were made possible primarily through photography of very close subjects. Many people have wondered about the possibility of achieving shallow DOF using automatic software, but such a solution is believed impossible. There is simply no way for the camera processor to know which objects lay outside of the intended focus zone. The manual application of software to blur selectively during postprocessing can achieve the intended result but is often labor intensive and is generally considered to produce inferior results to shallow DOF achieved optically.

As the title of this post suggests, I recently came across two potential solutions for achieving shallow DOF with digital compacts. The first, while not as novel as the second, will be available much sooner. onOne Software, the makers of several highly-regarded Photoshop plugins including Genuine Fractals, have announced FocalPoint, a product which "recreates the look of selective focus and tilt-shift lenses." As I mentioned above, the concept of applying selective blur during postprocessing is nothing new. However, this plugin has the potential to improve the ease with which quality results are achievable, particularly by those of us who aren't Photoshop wizards. The screenshot below, provided by onOne, gives a suggestion of the type of control possible with this software.


The product description states that "FocalPoint gives photographers a way to create realistic depth of field control, plane of focus control and selective focus to any image after it is photographed allowing for more control and precision. The focus bug control in FocalPoint has a tangible, hardware feel much like using a lens. It makes it fast for a photographer to define the "sweet spot" either in a round shape or a plane and then control how much and of what kind of blur they would like to add. This has a huge benefit over hardware tools like auxiliary lenses and filters because it allows the photographer to control the focus after the image is taken, giving them more control and requiring fewer shots in camera." FocalPoint will be available in April for $159.95. I plan to download the demo at that time and will report back on my experiences with it.

The second potential solution meantioned earlier comes from Stanford University by way of Engadget. Researchers at Stanford are preparing a "multi-aperture camera." The pixels (sensels) of the 3MP sensor are 0.7 microns across and arranged in groups of 256 pixels. Each 256-pixel group is associated with it's own tiny lens. That makes more than 12,000 lenses! While this technology is expected to produce an image where everything is in focus, the spatial distribution of the lenses is such that any point in the image will be captured by at least four lens-sensor units, each from a slightly different perspective. This will allow precise determination of distances to all subjects in a given photo, much the same way two eyes provide a means for depth perception in human vision. The recorded distance information will make it possible to selectively defocus based on subject distance using software.


The image shown above doesn't look like anything we'll be throwing in a pocket any time soon. However, according to the article at PhysOrg.com, the multi-aperture camera will "look and feel like an ordinary camera, or even a smaller cell phone camera. The cell phone aspect is important, Fife said, given that 'the majority of the cameras in the world are now on phones.'" The many applications of this technology go far beyond that of achieving a shallow DOF with digital compacts, so be sure to check out the Physorg.com article for further information.