50×10

50x10 refers to a common aspect ratio used in visual media, particularly in film and video production. The notation 50x10 signifies a field of 50 horizontal scan lines and 10 scan lines per millimeter. This ratio was historically relevant in early television broadcasting standards. The concept of scan lines is fundamental to how analog and early digital video signals were transmitted and displayed, with the image being rendered as a series of horizontal lines. A higher number of scan lines generally indicated a higher resolution and a more detailed image.

The 50x10 ratio was part of a system designed to balance image quality with the technical limitations of the time, including bandwidth constraints for broadcasting. While not a measure of the final displayed aspect ratio in terms of width to height (like 4:3 or 16:9), it described a characteristic of the signal's vertical resolution and density. Understanding such technical specifications is important for historical context when studying the evolution of television technology and video engineering. The development and adoption of different scan line standards and aspect ratios have shaped the visual experience over decades.