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vonpietro
08-11-2019, 08:25 PM
HI again,

I've got a shot where i'm rendereing out a chan element with bullet. it crashes down on a plane. I'm just rendering the element.
but i need a shadow pass -

I've got it currrently with a white bg floor and the plan is to render the same pass out with objects excluded or turned off so that just the shadow shows.
the shadow will be on white, and i dont think i get an alpha of the shadow.

anyone know how to isolate a shadow pass better than this?

I didn't see a shadow buffer - i wonder if this is a buffer newtek could add in the future - sure would be useful just to have a shadow buffer pass.

does exr save out a shadow buffer pass - or the photoshop export?

thanks

vonpietro
08-11-2019, 10:01 PM
ok found the shadow catcher shader type

happy to see it works like a charm - u put a floor there - set it to shadow catcher - and
bam - when you render your element it has the shadows built into the alpha -

perfect
solved the problem of getting shadows out of lw.

RPSchmidt
08-12-2019, 07:41 AM
Quick notes on shadow catcher if you haven't used it before.

The shadow catcher shader does work great... but make sure you uncheck glossy reflections and zero out specular or it will act like a reflective surface in your render output.... rather, you will get shadows AND reflections.

Also, if you are using an HDRI for lighting, the portions of the shadow catcher where the shadow is will show the HDRI through them.

You can solve this by going to the compositing tab and loading a 1 pixel black JPEG in the Background image. You will still have the benefit of your HDRI lighting but the shadows will only be in shades of black, i.e., normal shadows.