In search of ultimate beauty one area of camera work is exceptionally important. Whether the ‘bokeh’ or the framing is to be perfected it is the lens that has the most effect on the end result. Automating the lens control is thus an important matter to discuss. To make life bit more complicated lens functions are not independent from sensor characteristics and there are no standard control interfaces.
The first obstacle to building an automated camera platform is physical compatibility of the capture unit and the lens. Naturally the ring has to be the right size or adapters need to be used. Also lens registration ie. lens distance from sensor has to be right. Since both of these require fine mechanical work the parts need specialist work. Nevertheless this is the simple part of interfacing lenses and custom sensors. Unfortunately using a manual focus lens would limit the artistic expression profoundly.
To control a motorized lens an electronic interface is needed. The challenge is that there are just propriatory protocols in the market. Each lens vendor has their own serial custom data interface and peculiar physical connector type for the lens. Consequently it is no simple task to build a portable control unit that could control aperture and focus in variety of lenses.
The prices of broadcast quality lenses are high. A single lens can cost just as much as the camcorder itself. Subsequently it would be easiest to start the development work using a lens from a standard 35mm still camera (SLR). Just a deapth of Field (DOF) adapter is needed. The main differences between video camcorder lenses and SLR lenses are in the image stabilization technology. One is more suited for panning and the other is more adapted compensating for sudden jerks.