The remain physical components to be build for the Open Telecine are: aperture, lighting, optics (adjust wheel and cone), body, and film guide wheels. The part that was manufactured in this blog was the aperture. The images show the final aperture in pieces and assembled.
According to Wikipedia, "In optics, an aperture is a hole or an opening through which light travels. More specifically, the aperture of an optical system is the opening that determines the cone angle of a bundle of rays that come to a focus in the image plane. The aperture determines how collimated the admitted rays are, which is of great importance for the appearance at the image plane. If an aperture is narrow, then highly collimated rays are admitted, resulting in a sharp focus at the image plane. If an aperture is wide, then uncollimated rays are admitted, resulting in a sharp focus only for rays with a certain focal length. This means that a wide aperture results in an image that is sharp around what the lens is focusing on and blurred otherwise. The aperture also determines how many of the incoming rays are actually admitted and thus how much light reaches the image plane (the narrower the aperture, the darker the image for a given exposure time)."
The 8mm aperture was build in a small body that will compress the film between two planes: a fixed plane and a leaf spring. This allows the film to slide through with kinks and bumps (e.g. between the feeder film and film). The plastic grain is extruded to align parallel with the film, thus making a smoother contact surface. The current aperture is 8mm x 8mm, making it project the entire surface of the film. This include the sprocket holes and edges. The hopes are that the sprocket holes will help in detecting the film speed and frame position when using image processing (e.g. Canny edge detection).
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