green tint wb on ex1r at DVinfo.net

Jim Stamos · September 11th, 2011, 03:51 PM

sometimes when im setting my wb theres a major green tint. wb on a white background with my led light and the yellow filter on it. very odd.

Cees van Kempen · September 12th, 2011, 10:10 AM

Jim , I once experienced the same with certain settings. I started a trhread about that "white balance in PP different from A/B" at June 6th this year and got the answer from some people who knew what was happening. Please search for this thread, it may have the answer for you too.

Alister Chapman · September 15th, 2011, 12:39 PM

LED lights do not have a full spectrum output. A white LED bulb is normally constructed using a blue LED with a phosphor coating that absorbs some of the blue and re transmits it as red/green. As the blue LED only produces a very narrow bandwidth of blue light the result is an uneven light source with gaps and holes in the spectrum produces. Our eyes tend to disregard these gaps and holes, but the electronic sensor of a video camera see's these gaps and spikes and the end result is unusual colour casts or peculiar looking colours.

Robert Turchick · September 15th, 2011, 03:06 PM

LED was the red flag that went up for me too upon reading your issue. Instead of yellow filter, try a minus green on the LED. If it's a daylight fixture (which all of mine are) I white balance with a warm card which seems to help a lot.

September 11th, 2011, 03:51 PM	#1
Jim Stamos Major Player Join Date: Jun 2008 Location: Houston, TX Posts: 563	green tint wb on ex1r sometimes when im setting my wb theres a major green tint. wb on a white background with my led light and the yellow filter on it. very odd.

September 12th, 2011, 10:10 AM	#2
Cees van Kempen Major Player Join Date: Jan 2010 Location: Nieuw-Vossemeer, The Netherlands Posts: 455	Re: green tint wb on ex1r Jim , I once experienced the same with certain settings. I started a trhread about that "white balance in PP different from A/B" at June 6th this year and got the answer from some people who knew what was happening. Please search for this thread, it may have the answer for you too.

September 15th, 2011, 12:39 PM	#3
Alister Chapman Inner Circle Join Date: Dec 2005 Location: Bracknell, Berkshire, UK Posts: 4,957	Re: green tint wb on ex1r LED lights do not have a full spectrum output. A white LED bulb is normally constructed using a blue LED with a phosphor coating that absorbs some of the blue and re transmits it as red/green. As the blue LED only produces a very narrow bandwidth of blue light the result is an uneven light source with gaps and holes in the spectrum produces. Our eyes tend to disregard these gaps and holes, but the electronic sensor of a video camera see's these gaps and spikes and the end result is unusual colour casts or peculiar looking colours. __________________ Alister Chapman, Film-Maker/Stormchaser http://www.xdcam-user.com/alisters-blog/ My XDCAM site and blog. http://www.hurricane-rig.com

September 15th, 2011, 03:06 PM	#4
Robert Turchick Trustee Join Date: Oct 2009 Location: Mesa, AZ Posts: 1,389	Re: green tint wb on ex1r LED was the red flag that went up for me too upon reading your issue. Instead of yellow filter, try a minus green on the LED. If it's a daylight fixture (which all of mine are) I white balance with a warm card which seems to help a lot. __________________ The older I get, the better I was!