USB ID: VID_054C&PID_0013
Professional trackball of excellent quality, designed for Sony's TV-production equipment. Note that despite it's a USB trackball, it is (in original state) not a pointing device in traditional sense: OS will report it as a Vendor Specific Device Type. In other words, you can't use it as normal HID mouse without heavy modding.
Device comes with additional horseshoe-shaped wrist rest, and is quite comfortable with it.
Ball of 44mm size supported by 5mm steel shafts with 693ZZ ball bearings, and even scroll wheel uses giant 6810Z NSK ball bearing, so rotation is incredibly smooth (users of Kensington Expert will understand what I mean).
Additional A to F buttons are of illuminated type: green LED is embedded into each switch.
Highly complicated logic components are used. Main controller is 16-Bit 64F2238ATE13, with added Altera MAX EPM7128AETC100-10 PLD and OKI L60851D USB controller. Also, Maxim MAX3221 serial receiver is present: probably, intended for firmware loading/update. Optical sensors for 36-slot X and Y shutter discs and for 240-slot scrollring are marked OPIC (can't find datasheet).
Design and manufacturing quality is outstanding: everything is shielded and grounded (even scrollring!), each component is clearly marked on PCB, and even test points are not simple copper circles but special soldered contacts for convenience of probe connection. Diagnostic LEDs and block of DIP switches are present on board, but its function is unknown to me. It's definitely a finest optomechanical trackball I've ever encountered (and I've seen quite many of them).
One negative point is, extremely fragile black plastic of ball cage / bearings retainer frame: it became so brittle that literally broke in several places during transportation and disassembly. Dual-compound cyanoacrylate glue fixed everything, though.
Calculated resolution is 326 PPR / 60 CPI.
It seems two versions were manufactured: ivory described above, and grey:
Sony's PDF for set of DMW-Cx-series controls:
https://trackballs.eu/media/Sony/DMW-C4/DMW-Cx.pdf
Article about conversion to HID pointing device is currently in progress.