Lens & Camera

The machine vision camera has a 2/3" 1388 x 1036 pixel sensor with Bayer pattern filter (Sony ICX285AK CCD). The pixel size is 6.45um, which in theory should give about two stops better dynamic range over a typical 1/3" 4.7um sensor. In practice, I get about one and a half stops improvement.

The macro lens is actually an enlarger lens, reverse mounted as it is necessary to magnify to go from R8/S8 to fill the CCD. It is mounted on extension tubes to allow close focussing.

The lens is a Schneider Componon-S mounted by its 43mm filter thread. A stepping ring from 43mm to 52mm is used together with a 52mm to 42mm reversing ring. The extension tubes are 42mm manual tubes as used on 35mm cameras with the Praktica threaded mount.

To mount the extension tubes to the camera's C-mount, I turned up a 42mm to C-mount adapter out of Delrin material.

Left-right and fine focussing adjustment is made with two micrometer driven linear slides. Height adjustment is made by separating two metal blocks via adjustment screws. The whole assembly can move towards/away from the projector to provide for initial coarse focussing adjustment.