Which type of iris is NOT typically recognized in video technology?

In the context of video technology, the term "iris" refers to the mechanism that controls the amount of light entering a camera lens, impacting exposure and depth of field. Fixed, DC-Iris, and P-Iris are all recognized types of iris adjustments utilized in video cameras.

Fixed iris lenses have a set aperture that does not change, which is suitable for environments with consistent lighting conditions. DC-Iris operates by dynamically adjusting the aperture size in response to changing lighting conditions, utilizing an electrical signal to optimize exposure. P-Iris, or Precision Iris, enhances the control over the aperture by providing precise adjustments, allowing for better image quality and depth of field management.

On the other hand, while the concept of a variable iris might be understandable, it is not a standard term used in video technology to describe a specific type of iris mechanism. The more precise classifications such as DC-Iris and P-Iris capture the functionalities relevant to dynamic and precise control needed in modern imaging technologies. Thus, the term "variable-iris" does not align with the recognized categories of iris technology used in the industry, making it the correct choice for which type is not typically recognized.