3D focussing gives the photographer an additional degree of freedom in image composition. Objects of different distance can be focussed at the same time, independent of their arrangement or viewers position.
Pure mathematics is the heart of CAPcam. The skeleton is a hexapod built from six high precision electronic drives. Instead of mechanical calibrations (shimming) any optical and mechanical characteristics are stored within the definition file delivered with each lens or digital back.
CAPcam comes into play when every pixel counts. New high resolution digital backs deliver more details within the depth of Field (DOF). But this area of focus becomes smaller with higher resolution.
Using a 80MPx back with 80mm lens at F4.0 results in a DOF of 15mm at 1m distance. This means that only objects within 992.5mm to 1007.5mm distance will benefit from that high resolution. Closing the aperture to F16 slightly extends the DOF to 970mm until 1030mm but results in significantly reduced resolution. (see: The advantage of 3D focussing and The small difference between 'almost sharp' and 'sharp')
By aligning the focal plane along a surface in the scene, 3D focussing allows to get the maximum image quality out of a high resolution digital back.
Selective focus is used to direct the viewer's attention to a small part of the image while de-emphasizing other parts.
CAPcam allows to align the focal plane freely in the scene - intuitive and precise directly from your computer.