Help with my "IRIS" at DVinfo.net

Allen Thok · October 21st, 2005, 04:07 AM

I'm so new to this DV game, will some please explain to me what the "iris" control means on my XL2...actually what is "iris"....also what is the appropriate setting for a movie shoot..Some told me it should be f4.0...don't even know what that means...please someone help me and explain it ...thanks

Pete Bauer · October 21st, 2005, 05:22 AM

Hi Allen,

The iris of a camera is a device to control the amount of light passing to the sensor. It has leaves arranged in a circle that expand and contract to create a smaller or larger opening -- called the aperture -- to adjust the amount of light that passes through. (Sorry, being on short time this morning I couldn't find a picture of a camera iris to link). This is very similar to your own eye; the colored part of your eye is the iris, and your pupil is the aperture. In dim light, your iris thins out to make a larger pupil (larger aperture). More light gets through to your retina. In bright light, your iris expands to reduce the iris (aperture) and therefore the amount of light passing by.

Setting your aperture, along with all the other parameters of your camera, to get a great picture is a combination of art and science. Since you're new to it all, I'd highly recommend picking up an inexpensive basic photography book to learn about iris, aperture, f-stop, shutter, focal plane, lense elements, basic lighting techniques, etc etc. To give you a jump-start, I did a quick internet search and found this fellow's personal web site that has a fairly nice discussion of f-stop:

http://www.uscoles.com/fstop.htm

Give that a quick read and come on back for your follow-up questions!

Cheers.

October 21st, 2005, 04:07 AM	#1
Allen Thok New Boot Join Date: Aug 2005 Posts: 17	Help with my "IRIS" I'm so new to this DV game, will some please explain to me what the "iris" control means on my XL2...actually what is "iris"....also what is the appropriate setting for a movie shoot..Some told me it should be f4.0...don't even know what that means...please someone help me and explain it ...thanks

October 21st, 2005, 05:22 AM	#2
Pete Bauer Wrangler Join Date: May 2003 Location: Eagle River, AK Posts: 4,100	Hi Allen, The iris of a camera is a device to control the amount of light passing to the sensor. It has leaves arranged in a circle that expand and contract to create a smaller or larger opening -- called the aperture -- to adjust the amount of light that passes through. (Sorry, being on short time this morning I couldn't find a picture of a camera iris to link). This is very similar to your own eye; the colored part of your eye is the iris, and your pupil is the aperture. In dim light, your iris thins out to make a larger pupil (larger aperture). More light gets through to your retina. In bright light, your iris expands to reduce the iris (aperture) and therefore the amount of light passing by. Setting your aperture, along with all the other parameters of your camera, to get a great picture is a combination of art and science. Since you're new to it all, I'd highly recommend picking up an inexpensive basic photography book to learn about iris, aperture, f-stop, shutter, focal plane, lense elements, basic lighting techniques, etc etc. To give you a jump-start, I did a quick internet search and found this fellow's personal web site that has a fairly nice discussion of f-stop: http://www.uscoles.com/fstop.htm Give that a quick read and come on back for your follow-up questions! Cheers. __________________ Pete Bauer The most beautiful thing we can experience is the mysterious. It is the source of all true art and science. Albert Einstein Trying to solve a DV mystery? You may find the answer behind the SEARCH function ... or be able to join a discussion already in progress!