New Picture Profiles with T1 filter at DVinfo.net

William Japhet · February 15th, 2010, 05:45 PM

I begin this thread to collect Picture Profiles edited or modified when using this filter.

Please add your comments or tips to avoid this "green tint", or if someone has mesured (really) the color correction applied with it, please inform us.

Regards,
William.

Kevin Spahr · February 17th, 2010, 12:45 PM

I had suggested creating a PP for use with the T1 in another thread months ago which had the same response as this one. I always white balance but I can still see some minor color tint when I use the T1, although the brown-black issue without the T1 would be much harder to live with.

Wouldn't it be nice if someone at Tiffen would create some default PPs for their filters? They surely have the equipment and the know-how - if they needed a camera I'm sure all they would have to do is ask on this forum and someone would gladly help them out.

Enough bitching, sorry...

William, my thought was to start out with a flat PPs for tungsten, fluorescent, and daylight sources and then create PPs for the same light sources that would be corrected for when you put on the T1. If I used LED or HMI lights I would consider having a PP for the spectrum of light produced by these sources too. I would think that a white balance should also be done when using the new PPs so it would be more accurate for each real lighting condition.

I guess ONE of the adjustment that this would require would be fiddling with the color matrix. My understanding is that white balance effects the gain on the red and the blue channels. So the green channel could be considered the pivot point in this adjustment (it does not get gain added or removed) and white balance looks more at the brightness of these channels. Where as in the matrix you can finely adjust the interaction between any and every two channels of color (ie R-G, G-R, etc).

Anybody have comments on this theory of approaching the issue?

I'm only lacking the know-how and equipment to do this properly but I would consider trying to "eyeball" a setting if I knew I was going down the right path. I don't think that it is possible to reverse all the tint caused by the filter since everything between the imager and the subject causes some effect, but I think it could be made better.

Clark Peters · February 17th, 2010, 01:10 PM

I think eyeballing matrix settings would be a bad idea. At least pointless.

Bill Ravens posted a lot about a process he borrowed. This is the link he posted: JVC HD100 Calibration

His specific process for the EX-1 is at post #64 in the Picture Profiles sticky.
Pete

February 15th, 2010, 05:45 PM	#1
William Japhet Regular Crew Join Date: Mar 2009 Location: Paris (France) Posts: 28	New Picture Profiles with T1 filter I begin this thread to collect Picture Profiles edited or modified when using this filter. Please add your comments or tips to avoid this "green tint", or if someone has mesured (really) the color correction applied with it, please inform us. Regards, William.

February 17th, 2010, 12:45 PM	#2
Kevin Spahr Major Player Join Date: Feb 2005 Location: Carlisle, PA Posts: 451	Since no one else will say anything... I had suggested creating a PP for use with the T1 in another thread months ago which had the same response as this one. I always white balance but I can still see some minor color tint when I use the T1, although the brown-black issue without the T1 would be much harder to live with. Wouldn't it be nice if someone at Tiffen would create some default PPs for their filters? They surely have the equipment and the know-how - if they needed a camera I'm sure all they would have to do is ask on this forum and someone would gladly help them out. Enough bitching, sorry... William, my thought was to start out with a flat PPs for tungsten, fluorescent, and daylight sources and then create PPs for the same light sources that would be corrected for when you put on the T1. If I used LED or HMI lights I would consider having a PP for the spectrum of light produced by these sources too. I would think that a white balance should also be done when using the new PPs so it would be more accurate for each real lighting condition. I guess ONE of the adjustment that this would require would be fiddling with the color matrix. My understanding is that white balance effects the gain on the red and the blue channels. So the green channel could be considered the pivot point in this adjustment (it does not get gain added or removed) and white balance looks more at the brightness of these channels. Where as in the matrix you can finely adjust the interaction between any and every two channels of color (ie R-G, G-R, etc). Anybody have comments on this theory of approaching the issue? I'm only lacking the know-how and equipment to do this properly but I would consider trying to "eyeball" a setting if I knew I was going down the right path. I don't think that it is possible to reverse all the tint caused by the filter since everything between the imager and the subject causes some effect, but I think it could be made better.

February 17th, 2010, 01:10 PM	#3
Clark Peters Regular Crew Join Date: Nov 2007 Location: Manhattan, Kansas Posts: 123	I think eyeballing matrix settings would be a bad idea. At least pointless. Bill Ravens posted a lot about a process he borrowed. This is the link he posted: JVC HD100 Calibration His specific process for the EX-1 is at post #64 in the Picture Profiles sticky. Pete