Iris/exposure Fluctuates!!! at DVinfo.net

Joseph Andolina · April 9th, 2006, 12:31 AM

Is this normal, or is it not? I shoot manual all the time with my XL2 & 20X lens, mostly in 24pn. Why do I still see a fluctuation in exposure when panning the camera or if someone might move slightly off frame or into frame? I notice it mostly if I'm pointed at a white wall. Also, the indicator when looking in the VF indicates it fluctuating. I don;t see anything on the lens itself to make sure exposure is maunual.

Tony Davies-Patrick · April 9th, 2006, 01:21 AM

Have you left the White Balance and Gain dB on "A"? This will also cause the exposure to fluctuate during a pan, so it is better to leave the balance button locked or on 1 and the gain on 0 or -3dB. If you are not in Manual, but in AV or TV, try to also press the exposure lock prior to panning.

Tom Hardwick · April 9th, 2006, 01:24 AM

And have you checked to see that your shutter speed is locked down?

Joseph Andolina · April 9th, 2006, 01:47 AM

Everything is off A. Gain always set at 0, and I never use A setting for white ballance. I used a white ballance I had stored in position 3.

Tony, as far as shutter speed, I use 1/48 shutter speed especially when shooting 24pn. As far as locking it down, I've never noticed any setting where it can be locked down. Am i missing something? My view finder always indicates it staying on 1/48 while shooting.

Joseph Andolina · April 9th, 2006, 12:18 PM

Is there a setting for manual iris on the 20X lens? Bottom line it seems that the iris setting fluctuates as indicated in the viewfinder, bobbing back and forth as I'm panning the camera toward the white wall. Or is a manual iris setting only possible on the manual lens?

Ash Greyson · April 9th, 2006, 12:40 PM

The indicator will always fluctuate in anything but auto which will always try to center it. If you frame things cinematically the indicator is useless as it indicates the exposure of the entire frame, not the subject you may be focusing on. So dont even look at the indicator.

What mode are you in? The some of the modes trump the manual settings...

ash =o)

Joseph Andolina · April 9th, 2006, 01:08 PM

I'm in "M" (manual) mode. I never really use AV or TV, etc... when shooting.

BTW, thanks for all your responses :)

Hopefully there's some answer to what I'm seeing.

My exact settings are the following: M mode, manual focus, manual White ballance, 1/48 shutter , 24pn frame rate & 0 gain.

Jesse Redman · April 12th, 2006, 09:40 PM

Joseph,

Do you see these fluctuations in your NLE?

- Jesse

Tony Davies-Patrick · April 13th, 2006, 03:15 AM

Filming outdoors where light intensity can change dramatically within seconds, working in MF mode - by adjusting both iris and shutter speeds - may sometimes take too much time to keep up with the rapidly changing light levels.

Some of my work is in MF mode, but I often prefer to work in AV mode (brought over from my years in still photography), as this gives me full and instant exposure control.

In AV mode, just one press of the exposure lock button provides a non-fluctuating exposure during a long pan between light and dark areas of the scene.

Pressing the exposure lock button also provides both the shutter and iris readings in the viewfinder, and the odd click of the +- EV dial helps provide added adjustments when you shoot directly towards the sun or a bright background.

Joseph Andolina · April 16th, 2006, 06:07 PM

thanls again for all responses. i will try seeing what i can acheive in AV mode.

Greg Boston · April 16th, 2006, 06:12 PM

Quote:

Originally Posted by Tony Davies-Patrick

Filming outdoors where light intensity can change dramatically within seconds, working in MF mode - by adjusting both iris and shutter speeds - may sometimes take too much time to keep up with the rapidly changing light levels.

Some of my work is in MF mode, but I often prefer to work in AV mode (brought over from my years in still photography), as this gives me full and instant exposure control.

In AV mode, just one press of the exposure lock button provides a non-fluctuating exposure during a long pan between light and dark areas of the scene.

Pressing the exposure lock button also provides both the shutter and iris readings in the viewfinder, and the odd click of the +- EV dial helps provide added adjustments when you shoot directly towards the sun or a bright background.

Like you Tony, I also like shooting in Av mode. It lets me keep the iris wide open for minimum DOF when desired and I usually click the AE offset just enough to eliminate most zebras (within contrast limits of course). I find that the AE in zero offset is a bit on the 'hot' side exposure wise.

-gb-

April 9th, 2006, 12:31 AM	#1
Joseph Andolina Regular Crew Join Date: Mar 2004 Location: Everett, WA Posts: 178	Iris/exposure Fluctuates!!! Is this normal, or is it not? I shoot manual all the time with my XL2 & 20X lens, mostly in 24pn. Why do I still see a fluctuation in exposure when panning the camera or if someone might move slightly off frame or into frame? I notice it mostly if I'm pointed at a white wall. Also, the indicator when looking in the VF indicates it fluctuating. I don;t see anything on the lens itself to make sure exposure is maunual.

April 9th, 2006, 01:21 AM	#2
Tony Davies-Patrick Trustee Join Date: Feb 2005 Location: Worldwide Posts: 1,589	Have you left the White Balance and Gain dB on "A"? This will also cause the exposure to fluctuate during a pan, so it is better to leave the balance button locked or on 1 and the gain on 0 or -3dB. If you are not in Manual, but in AV or TV, try to also press the exposure lock prior to panning. __________________ www.WILDCARP.com www.NIKON.me.uk

April 9th, 2006, 01:08 PM	#7
Joseph Andolina Regular Crew Join Date: Mar 2004 Location: Everett, WA Posts: 178	I'm in "M" (manual) mode. I never really use AV or TV, etc... when shooting. BTW, thanks for all your responses :) Hopefully there's some answer to what I'm seeing. My exact settings are the following: M mode, manual focus, manual White ballance, 1/48 shutter , 24pn frame rate & 0 gain. Last edited by Joseph Andolina; April 9th, 2006 at 05:44 PM.

April 13th, 2006, 03:15 AM	#9
Tony Davies-Patrick Trustee Join Date: Feb 2005 Location: Worldwide Posts: 1,589	Filming outdoors where light intensity can change dramatically within seconds, working in MF mode - by adjusting both iris and shutter speeds - may sometimes take too much time to keep up with the rapidly changing light levels. Some of my work is in MF mode, but I often prefer to work in AV mode (brought over from my years in still photography), as this gives me full and instant exposure control. In AV mode, just one press of the exposure lock button provides a non-fluctuating exposure during a long pan between light and dark areas of the scene. Pressing the exposure lock button also provides both the shutter and iris readings in the viewfinder, and the odd click of the +- EV dial helps provide added adjustments when you shoot directly towards the sun or a bright background. __________________ www.WILDCARP.com www.NIKON.me.uk

April 9th, 2006, 01:24 AM	#3
Tom Hardwick Inner Circle Join Date: Mar 2003 Location: Billericay, England UK Posts: 4,711	And have you checked to see that your shutter speed is locked down?

April 9th, 2006, 01:47 AM	#4
Joseph Andolina Regular Crew Join Date: Mar 2004 Location: Everett, WA Posts: 178	Everything is off A. Gain always set at 0, and I never use A setting for white ballance. I used a white ballance I had stored in position 3. Tony, as far as shutter speed, I use 1/48 shutter speed especially when shooting 24pn. As far as locking it down, I've never noticed any setting where it can be locked down. Am i missing something? My view finder always indicates it staying on 1/48 while shooting.

April 9th, 2006, 12:18 PM	#5
Joseph Andolina Regular Crew Join Date: Mar 2004 Location: Everett, WA Posts: 178	Is there a setting for manual iris on the 20X lens? Bottom line it seems that the iris setting fluctuates as indicated in the viewfinder, bobbing back and forth as I'm panning the camera toward the white wall. Or is a manual iris setting only possible on the manual lens?

April 9th, 2006, 12:40 PM	#6
Ash Greyson Trustee Join Date: May 2003 Location: Tulsa, OK Posts: 1,689	The indicator will always fluctuate in anything but auto which will always try to center it. If you frame things cinematically the indicator is useless as it indicates the exposure of the entire frame, not the subject you may be focusing on. So dont even look at the indicator. What mode are you in? The some of the modes trump the manual settings... ash =o)

April 12th, 2006, 09:40 PM	#8
Jesse Redman Regular Crew Join Date: Mar 2006 Location: Cedar Park, Texas Posts: 182	Joseph, Do you see these fluctuations in your NLE? - Jesse

April 16th, 2006, 06:07 PM	#10
Joseph Andolina Regular Crew Join Date: Mar 2004 Location: Everett, WA Posts: 178	thanls again for all responses. i will try seeing what i can acheive in AV mode.