Check out the EOS 1D C Product Manual online (PDF).
Or the EOS-1D C Total Movie Recording Time and File Size Per Minute Chart (PDF).

Production
Because of its compact and rugged design, the EOS-1D C is flexible across a diverse range of shooting environments and setups: small spaces, embedded on a vehicle or on-set, at the end of a crane or jib, etc. Using the (optional) Canon WFT-E6A Wireless File Transmitter, users can also control recording remotely with Canon’s EOS Utility Software.

Like other Cinema EOS products, the EOS-1D C exhibits incredible low-light performance, helping to ensure optimum image quality under conditions of extremely low scene illumination. When operating in DSLR mode the EOS-1D C offers top-of-the range focusing, exposure, and burst mode.

Post-Production
The EOS-1D C records the 4K signal as a YUV 4:2:2 at 24p Motion JPEG format directly to onboard CF cards. It can also externally record an HD time-coded proxy via HDMI output for use in an offline NLE system. The 4K file can be loaded directly into color grading systems that support the Motion JPEG file format; and the alternative HD recordings (H.264) on the CF cards can also be taken directly into color grading systems.

Canon 18.1 Megapixel Full-Frame CMOS Sensor
The EOS-1D C carries the latest generation of Canon's Full-Frame CMOS sensor. With a Full-Frame sensor, Canon EF and EF Cinema lenses will perform to their true potential, while improved signal-to-noise ratio provide clearer shadows and highlights in both bright and low-light environments. Achieve high quality results across the ISO range from 100 to 51200, expandable from ISO 50 to 204800. The sensor in the EOS-1D C also minimizes the rolling shutter effect with a high-speed read across the sensor bus for true-to-life images.

4K Motion JPEG YCbCr 4:2:2, 8-bit video recording
The EOS-1D C is a completely self-contained device that captures 4K video in a cropped-sensor configuration at 24fps in YCbCr color space with a sampling ratio of 4:2:2 and 8-bit depth. Color and luminescence are preserved, while footage can easily adapt to existing post-production workflows without conversion. 4K video can be monitored on the camera's rear LCD, or HD video can be output via HDMI to an external recorder for proxy editing. 4K files can also be played in native resolution using the EOS MOVIE Player.

Full HD Recording and Super 35mm Crop Mode
In addition to standard frame rates of 30fps, 25fps and 24fps, the EOS-1D C also enables Full HD recording at 60fps and 50fps and supports high-speed shooting for spectacular slow-motion footage. The camera's built-in LCD monitor can both preview and play back footage at its native frame rate. The EOS-1D C also supports Super 35mm Crop in Full HD at 30fps, 25fps, and 24fps. Image compression is H.264 and HDMI support permits external monitoring and playback of footage independent of shooting mode. When monitoring Super 35mm Crop images, the monitor automatically masks the image to aid composition.