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Next Question: Blocking in Live Action


TommyDAQ2

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Ok, onto my next question... I searched the forums but didn't find what I was looking for. I probably just didn't have the right terms....

 

But now, I want to have Woody walk through a live action scene. He's going to come out from behind something.

 

Scenario: I have a still of the interior of a bar. I want Woody to enter the scene at the back of the shot, entering from the far end of the bar. Therefore ,when he first enters, the bar is blocking the lower part of his body from being scene. Please remind me as to how to set an object in my scene so that it receives a projection map (I think - the camera rotoscope), but yet still has geometry that will block other geometry? Does that make sense?

 

I know I can set something as a shadow catcher only, but then it's geometry becomes invisible instead of rendering as an opaque block.

 

thanks,

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coulpe of things

are you rendering from the camera ?

command P will set you up with that

 

see attachment

 

if using Quicktime

you can set your movie compression from animation to non ect.. do that using the set tab

just once 1 frame

sometimes you have to do a quick switch from one of those settings to kick it in the pants

 

 

 

also make sure you set the location

where it says file name and that should the setup box match when you hit the render button

render_from_cam.png

render.png

render_to_file_box.png

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Ok, now I'm a bit confused. If I have Shadow Buffers checked, it renders the shadows on the projection mask, but won't render the character. If I uncheck Shadow Buffer, it renders the character, but no shadows. How do I get it to render the scene w/ the character and the shadows in one pass???

 

Thanks,

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You can see a quick test on YouTube...

 

http://youtu.be/5OeWDRmdTqw

 

I've got Woody entering a scene from behind the bar, and walking through the bar. He cast his reflections on the floor, but there are no shadows. If I turn on Shadow Buffers, it renders the shadows, but no characters.

 

My Setup:

 

Camera: Background image set to Camera Roto

Shadows ON

Reflections ON

Alpha buffer OFF

Shadow Buffer OFF

 

Ground:

Active: ON

Ambience: 50%

Front Projection: ON

Flat Shaded: OFF

Cast Reflections: ON

Cast Shadows: ON

Receive Shadows: ON

Shadows Only: OFF

 

Woody:

Active: ON

Ambience: not set

Front Projection: OFF

Flat Shaded: OFF

Cast Reflections: ON

Cast Shadows: ON

Receive Shadows: ON

Shadows Only: OFF

 

Any ideas?

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Any ideas?

 

Nice clip, will be very cute when he burns the bar down!

 

Without knowing your lighting setup, reflectivity values - it is only a guess - but my guess is perhaps your shadows are getting washed out? Perhaps they are there but you can't see them?

 

Here's example showing the difference with klieg z-buff shadows on a front projected, flat shaded ground with NO reflections (ie very dark, obvious) versus ray traced sun shadows on a ground with 50% reflectivity, front projected only (NOT flat shaded) - shadows are more subtle

kliegshadowsversusraytracereflectionFlatshaded.jpg

warblerFrontprojflatshadedweb.jpg

Edited by NancyGormezano
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If you want a transparent image of the character, with cast shadows, that you can overlay on live action, you need to render two passes, minimum.

One is the shadow pass, use "shadow only" with alpha turned off. You will add this to your live action scene with a multiply blend, which will make the white transparent anyhow.

 

The next layer is JUST the character. Make sure alpha channel is on, and add this over your live action shot.

 

You will have two image sequences to composite with the live action.

 

(You can't render the character + alpha + cast shadows as one image, if you intend to seamlessly overlay on live action)

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