Lens Iris Tutorial

By: IPVM Team, Published on Dec 19, 2016

Cameras, like humans, have irises. However, cameras have five types of iris options - fixed, manual, auto, P iris. In this tutorial, we explain the tradeoffs of each, how irises work and how they relate to shutter speed.

Controlling Light

******* ******* ***** ******** by ****** ********* *** width ** *** ******* (iris) ** *** ****** of **** *** ******* is **** (*******). **** *** ***** of *** ******* (****) is ********, **** ****** *******, ********** **** **** (or ****) ***** ******.

****'* **** * **** iris ***** **** ****** open ** ****** ******:

iris closed opened

*** ****'* * ****** showing *** ******* ** adjusting:

** *** *** ** too **** *****, *** image **** ** ****** out *** *** **** too ****** *****, *** image **** ** ****. Since ***** ****** ****** over ****, *** ****** has ** ** **** to ****** *** **** light ****** ** ***** the ******* **********. ****** are *** *** ** do ****. ***** *** multiple **** ******* *******, detailed *****.

Auto **** / *-**** / *-**

********* **** ****** **** in ***** ********: **** (DC ** *****), *-**** (precise), *** *-**.

  • ** **** **** ****** control *** **** ******* via ****** ***** **** the ****. ** **** iris ****** *** **** common, ***** *** * standard ***** ** **** the **** ** ********** by *** ******.
  • *-**** ****** *** * specific ******** ****** ** more ********* ******* *** iris, ***** ** ******** to ******* ********* ** image ******* **** **** iris ** ******* ******** conditions. *******,** *** *****, *-**** ****** ******* no ******* **********.
  • *-** ****** *** *** as ** ****, ********* ** **** and ********. ***** ****** are ******* ** *-****, but *** ** **** complex *********** **** ***** supplies **** ******** *********** to *** ******, **** control ** *****, ****, distortion **********, *** ****, instead ** **** **** control. *-** ****** *** rare, **** **** ******* camera *******, *** *********** similar ** *-**** ** terms ** **** *******.

***** **** **** **** and *-**** ******** *** connectors **** *******, **** are *** ***** **********. A ** **** **** lens *** ** **** on * *-**** ****** (though ******* ******** ******* iris *******), *** * P-Iris **** ********* **** not ********** *** **** a ** **** **** jack.

Fixed / ****** ****

****** ****-**** ** **** common, ***** *** *** lens ******** ***** ****** be ********** ** *** camera: ***** *** ******.

***** ****, ** *** name ******* ****** ** adjusted ** ***. ** is *** ** *** factory, ********* *** *** way **** ** ********* * ****. ***** **** ****** are ****** ** ***** form ****** *******, **** as ********* *** ****** cameras, *** ******** ** CS *** ***** ***** types.

****** **** ****** ***** the **** ** ** controlled ** ******** ******** a **** ** *** lens. ****** *** **** is ************ **** *** the *** **** ** all *** *** ******, manufacturers ********* ********* ******* manual **** ****** ****** fully ** **%+ **** to ******** *** ***** performance. ****** **** ****** are ******** *** ***** used ** **** ********** applications.

What ** ***?

*****, ***** *** *** given * ****** ** what **** **** ** use, ** *** **** popular ****** **** ******* (domes *** *******) ********* do *** *** *************** lenses.

** *** *******, ***** generally ** ******* *************** lenses, ** **** *** found * ***** ********** in ***** ******* ******* iris *****. *** ****-**** **** *************** *** **** *******.

*** ******* ** **** IP ******* ***** ********* adjust ********** **************** *** *************, ******** them ** ****** ***** strong *** ***** (**** shutter) ** ***** ******** (slow *******).

** **** ****** ******** P ****, ** ******* using ** ** ** may **** **** ******* benefits **** ***, ** any, *********. *******, ** do *** ********* ********* cameras ***** **** ******* DS **** **** ****** based ** **** *******.

Test **** *********

**** ***** ******** *******.

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