Xl2 and greenscreen at DVinfo.net

Brice LeCarre · August 25th, 2006, 10:51 AM

Hello all,
I am very interested in green screen extraction. I am doing some tests now with my new xl2. My question is, does changing image settings like Gamma Cine,Knee to High and Black to stretch have an negative effects and create unwanted artifacts on the edges?

Thank you very much
Brice

Brice LeCarre · August 26th, 2006, 12:34 AM

Well, I ran two tests in two different places with two different light kits and two different talents and It seems to me that shooting without any presets is the way to go when greenscreen keying. Any image enhancer creates unwanted artifacts that causes problems with keylight.

Brice

Jarrod Whaley · August 26th, 2006, 01:30 AM

What kinds of artifacts did you see? What image parameters did you test with? How exhaustive were your tests?

I wouldn't say that preset-free is necessarily the way to go--especially based on a couple of tests when the number of possible combinations is pretty massive. Dialing down the sharpness might help you pull a good key, since the edges around your subject will be smoothed and there will be less noise. For the latter of those two reasons, it seems like bumping up the coring might help as well. I can think of a lot of things I'd try.

Brice LeCarre · August 26th, 2006, 10:17 AM

Hi Jarrold
The artifacts looked like stair steps just on the edges with gamma set to cine knee to high and black to stretch. When I went back to default settings it disappeared and I was able to pull a decent key.

Brice

Jarrod Whaley · August 26th, 2006, 11:30 AM

Well, are those three adjustments really enough to determine that no presets should be used when shooting for chroma keying? The artifacts you speak of might have been due to only one of those parameters. Then there are all the other adjustments you never tried.

It just seems to me it pays to be thorough when testing particular situations with with this camera. If you're just going to shoot your greenscreen shots with no presets, then you're giving up a lot of the image control that makes this such a good camera.

Brice LeCarre · August 26th, 2006, 02:07 PM

I am sure I'll try other stuff soon like the skin correction settings. I must admit that when I had the settings mentioned in the original post, the image looked great. The good news is I am not shooting only greenscreen stuff.
Brice

August 25th, 2006, 10:51 AM	#1
Brice LeCarre New Boot Join Date: Jul 2006 Location: Gilbert, AZ Posts: 10	Xl2 and greenscreen Hello all, I am very interested in green screen extraction. I am doing some tests now with my new xl2. My question is, does changing image settings like Gamma Cine,Knee to High and Black to stretch have an negative effects and create unwanted artifacts on the edges? Thank you very much Brice

August 26th, 2006, 01:30 AM	#3
Jarrod Whaley Major Player Join Date: Jun 2006 Location: chattanooga, tn Posts: 721	What kinds of artifacts did you see? What image parameters did you test with? How exhaustive were your tests? I wouldn't say that preset-free is necessarily the way to go--especially based on a couple of tests when the number of possible combinations is pretty massive. Dialing down the sharpness might help you pull a good key, since the edges around your subject will be smoothed and there will be less noise. For the latter of those two reasons, it seems like bumping up the coring might help as well. I can think of a lot of things I'd try. __________________ -->jarrod whaley. www.oakstreetfilms.com

August 26th, 2006, 11:30 AM	#5
Jarrod Whaley Major Player Join Date: Jun 2006 Location: chattanooga, tn Posts: 721	Well, are those three adjustments really enough to determine that no presets should be used when shooting for chroma keying? The artifacts you speak of might have been due to only one of those parameters. Then there are all the other adjustments you never tried. It just seems to me it pays to be thorough when testing particular situations with with this camera. If you're just going to shoot your greenscreen shots with no presets, then you're giving up a lot of the image control that makes this such a good camera. __________________ -->jarrod whaley. www.oakstreetfilms.com

August 26th, 2006, 12:34 AM	#2
Brice LeCarre New Boot Join Date: Jul 2006 Location: Gilbert, AZ Posts: 10	Well, I ran two tests in two different places with two different light kits and two different talents and It seems to me that shooting without any presets is the way to go when greenscreen keying. Any image enhancer creates unwanted artifacts that causes problems with keylight. Brice

August 26th, 2006, 10:17 AM	#4
Brice LeCarre New Boot Join Date: Jul 2006 Location: Gilbert, AZ Posts: 10	Hi Jarrold The artifacts looked like stair steps just on the edges with gamma set to cine knee to high and black to stretch. When I went back to default settings it disappeared and I was able to pull a decent key. Brice

August 26th, 2006, 02:07 PM	#6
Brice LeCarre New Boot Join Date: Jul 2006 Location: Gilbert, AZ Posts: 10	I am sure I'll try other stuff soon like the skin correction settings. I must admit that when I had the settings mentioned in the original post, the image looked great. The good news is I am not shooting only greenscreen stuff. Brice