Abbreviated as USM, and associated with digital camera terminology, ultrasonic motor (also called ultrasonic focus motor ) is a term that is mainly used to describe the motor that controls the movement of the lens or focus ring. An ultrasonic focus motor is much quieter (almost near-silent) and also moves the focus lens or ring faster when compared to a standard motor. A USM is able to hold the lens in place with precision and accuracy at the exact instant the lens arrives at the correct focus when using the camera’s auto focus (AF) feature.
See “Digital Cameras” in the Quick Reference section of
Short for Ultra Wide Band, a wireless communications technology that can currently transmit data at speeds between 40 to 60 megabits per second and eventually up to 1 gigabit per second. UWB transmits ultra-low power radio signals with very short electrical pulses, often in the picosecond (1/1000th of a nanosecond) range, across all frequencies at […]
- uncompressed video
Captured video that has not been altered by the capture device or software to compress the data. Uncompressed video streams take up a lot of disk space and more transmission bandwidth but it provides the best quality.
To return to a previous state by undoing the effects of one or more commands. The undo command is a valuable feature supported by many software products. It lets you try unknown commands with less risk, because you can always return to the previous state. Also, if you accidentally press the wrong function key, you […]
Refers to the condition that occurs when a computer attempts to represent a number that is too small for it (that is, a number too close to zero). Programs respond to underflow conditions in different ways. Some report an error, while others approximate as best they can and continue processing. For example, if your computer […]
Refers to features that are not described in the official documentation of a product. This lack of documentation can occur for a variety of reasons, including oversight. More often, though, undocumented features are features that were included because they were useful to the programmers developing the product but were deemed either unnecessary or potentially dangerous […]