AfterFX CS3 -- 3D Light source/shadow transparency problems

[JediNight]

I'm trying to add some text with a light source casting shadows to an underlying video. I don't want the light source to alter the underlying video though. I don't find any kind of null or transparent layer that will still show a visible shadow off the text above.

I've tried playing the video in a 2nd composition, placing a solid color layer under the text in Comp1 and using keying or matte techniques to "bluescreen" out what I don't want. But nothing I try works correctly -- it always decays the actual shadow by like 50% at the same time.

Anyone have some insight into what I could do?

[floatuponourtears]

so... what you want is just your text to cast shadow over your video?

[Zarxrax]

so... what you want is just your text to cast shadow over your video?

If thats all you want to do just use drop shadow or radial shadow effect.

[JediNight]

It's a bit more complicated than that. The text starts out at a 90degree to the camera and gets illuminated as it turns to a normal facing, then slowly moves back on the Z-axis so the shadows are "moving".

I wanted to be able to cast shadows onto the video without having the above light source affecting the video as well, because it darkens out the corners of the video.

[kenzuka]

I do not use AE, so I might be wrong, but you could try putting your text and light source in one composition, without background (your composition setting must use alpha level). After that, you create a second composition which contains your video and in which you import the text+light composition.

Since the shadow of the text exists on the alpha level, but not the light source, it should work. Well I think so....

[floatuponourtears]

It's a bit more complicated than that. The text starts out at a 90degree to the camera and gets illuminated as it turns to a normal facing, then slowly moves back on the Z-axis so the shadows are "moving".

I wanted to be able to cast shadows onto the video without having the above light source affecting the video as well, because it darkens out the corners of the video.

Mhm... I'm still not exactly sure what you're trying to do, but if I'm right, this should work;

Well... just duplicate the text layer, place it as you would like, blur it, then animate its transparency.

[Zarxrax]

If you are using an actual light in after effects, check the material settings for the video layer. I think you can make it not be effected by the light.

[JediNight]

If you are using an actual light in after effects, check the material settings for the video layer. I think you can make it not be effected by the light.

I'll admit I thought about that but dismissed it without even trying. I just assumed if the video wasn't affected by the light source that it wouldn't accept the shadows either, we'll see.

[JediNight]

Yep, I'm retarded. I overlooked the fact that the video had both an Accept Lights and Accept Shadows option for Materials. Turn off Accept Light and the shadows show up perfectly without distorting the original video.

*face palm*