Disadvantages with P-Iris lenses?
  • Can anyone tell me any disadvantages using cameras with P-Iris lenses (other than they are usually on more costly cameras)? They were invented by a joint venture by Axis and Kowa Lens maker, and first were used with Axis cameras, but now seeing them on some Vivotek and other cameras. thanks

    P-iris lenses:
    http://www.axis.com/files/whitepaper/wp_p-iris_38023_en_1009_hi.pdf

    Different types of Iris control:
    http://www.axis.com/products/video/camera/about_cameras/iris.htm


  • Hi songdog welcome and thank you for your contributions to the forum. P-Iris is an interesting development by Axis, it effectively allows more collaboration between the lens and the camera in order to select the best aperture for optimum image quality, rather than this decision being made solely by the lens only.

    For example, in low-light situations a standard auto-iris lens would open the aperture fully to allow as much light as possible to reach the camera's sensor, however this will result in a more blurry image as well as a narrow depth of field. With P-Iris, the camera may decide that better image quality could be obtained by closing the aperture somewhat and boosting the gain of the signal from the sensor in software, in order to compensate for the lower light levels.

    I haven't yet done a side-by-side test with a standard auto-iris lens so I have no direct first-hand experience to report, but I do think it's a very good idea and can only be good for image quality. I have seen many good cameras let down by bad lens systems, so I know that the lens system is extremely important (to a large extent more so than the megapixel value, which most people fixate upon). Other than cost I can't imagine what other disadvantages there could be.

Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!