Match lighting between subjects [ANSWER]
Posted: Thu, 12th Apr 2007, 10:30pm
Post 1 of 7
OK, I read most of the posts on the forum
I am new at this and all, and my problem is this...
When using actor on a greenscreen and separate background, I am having trouble with the actor not remotely matching the background in lighting.
when I try to shift the lights to match the background lighting I wind up with hot spots and other issues that prevent a clean effect.
any general suggestions?
and another quick question...
the white point on "color difference" what is generally considered too low, as in you should retry the lighitng? I am often hitting numbers in the low 20s.
Posted: Fri, 13th Apr 2007, 12:22am
Post 2 of 7
Having lights match your background shot is important. But CompositeLab is amazing in it's ability to match shots together. When you click on your video clip on the timeline there is a tab called "Grade" from here there are tons of filters that will get you matching your shots instantly! You can adjust the subject in front of your greenscreen and the background that the subject is being composited onto. I would recommend adjusting both layers slightly instead of either the top layer or bottom layer drastically to match the other. This will probably give it a more natural look (In most cases). I do not understand your question about "color difference" because it really depends on each individual shot. You should simply choose the settings that look best to you. Remeber that you can add multiple layers of grade objects. Does this answer your question? If not just ask more specifically. Welcome to the community!
Posted: Fri, 13th Apr 2007, 12:28am
Post 3 of 7
It is fairly important to match the lighting conditions when shooting your foreground greenscreen and background plate elements. Grading can be used to fix stuff, and get it to match, but the closer you are to begin with, the better. Try to shoot all the scene elements under the same conditions. Ideally you use a set which gives you full control over the lighting, but for exterior shoots and such, at least you can shoot in similar weather conditions, and if you use the manual exposure controls on your camera, you can make sure that it matches that way as well.
A white point in the low twenties is not uncommon. As was mentioned, feel free to set it anywhere that gives the best results.
Posted: Fri, 13th Apr 2007, 3:09am
Post 4 of 7
Thanks both of you for your help.
I figured out the grade filters, that wasnt too much of a problem (old photoshop wiz). I can match the tone of the pictures, within reason, most of the time.
The problem was the contradictiory issue of perfectly lighting the greenscreen vs lighting the model for the enviroment she will be in.
Here is a link to an example... a sample of a model on the screen and background footage. I just learning right now, playing around:http://cellarstudio.com/xilstudio/theproblem.jpg
Also as slight aside, is there a problem with my green and lighting of it? I am not quite getting clean pulls from the screen, even with key grading and spill suppression.
Or is this just a "play with it until you get it" kind of problem
Posted: Fri, 13th Apr 2007, 8:32am
Post 5 of 7
One trick that can make lighting much, much easier is to increase the distance between your subject and the screen itself. That way you can light them both separately, without the lighting affecting each other.
Your screen is a bit too light-olive-green, I'd say. I'd expect a deeper, darker, richer green.
Check out the greenscreen in the 'Giant' example project that comes with CompositeLab. The lighting on it is awful (check out all the poor shadowing!), but the actual colour is much closer to what you should be getting.
Posted: Fri, 13th Apr 2007, 2:19pm
Post 6 of 7
First thing I would try on that shot is setting up the greenscreen outside. Either that, or get some gels for your lights to adjust the color temperature so it matches your exterior shot. And, as Tarn said, try to get more distance between your actress and the screen.
Posted: Fri, 13th Apr 2007, 8:49pm
Post 7 of 7
You couldn't have just filmed your actor in the woods? I know you can't do this if you have a CG shot or some weird background behind you. I don't know, perhaps you wanted to do an effect with it. But don't forget that just shooting real shots will always look better than green-screening it!