Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] I need help! => Topic started by: Luke on 2021-02-16, 02:25:29

Title: Help with shadowcatcher for studio lighting setup
Post by: Luke on 2021-02-16, 02:25:29
Hey all,

I having trouble getting the shadowcatcher to behave how I'm wanting, I have a basic studio set up - whereby i'm rendering out objects (Furniture) on a curved white backdrop, it's being illuminated by a hdri and a couple of corona lights. If I render the scene without the shadowcatcher it comes out exactly as I'm wanting, however, I need to be able to remove the backdrop in photoshop and compose the shadows in. The CShading_Shadows is too noisy, so that doesn't work.

Is there a way that I can do this with the shadowcatcher?

Basically, I'd like to not be able to see the shadowcatcher at all in my scene and just have the alpha with the shadows so that I can remove the background and comp my object and shadows into a new background in photoshop?

Any help would be greatly appreciated.

Thanks.
Title: Re: Help with shadowcatcher for studio lighting setup
Post by: wilbertvandenbroek on 2021-02-16, 07:54:00
Shadowcatcher do exactly what you need. Just apply to your background and set the mode to for compositting. Now you have a good alpha with your object. You need to render a separate background render with backdrop if you want to comp them both.
Title: Re: Help with shadowcatcher for studio lighting setup
Post by: romullus on 2021-02-16, 10:18:51
You can look at this topic to get some idea about basic studio setup: https://forum.corona-renderer.com/index.php?topic=11345.0 The scene is pretty old and probably isn't set-up with swapable background in mind, but if you will follow wilbertvandenbroek's advice, you should be able to figure it out.
Title: Re: Help with shadowcatcher for studio lighting setup
Post by: maru on 2021-02-16, 15:04:00
You should be able to achieve the result you need with the shadowcatcher material pretty much out of the box. Can you explain what seems to be wrong?

Here are some educational materials:

1) Our video tutorial (5 parts):
https://www.youtube.com/watch?v=9JDGmzZaMkE&feature=emb_title (https://www.youtube.com/watch?v=9JDGmzZaMkE&feature=emb_title)

2) A forum thread with a sample scene and renders:
https://forum.corona-renderer.com/index.php?topic=18936.0

Title: Re: Help with shadowcatcher for studio lighting setup
Post by: Luke on 2021-02-17, 00:27:22
You should be able to achieve the result you need with the shadowcatcher material pretty much out of the box. Can you explain what seems to be wrong?

Here are some educational materials:

1) Our video tutorial (5 parts):
https://www.youtube.com/watch?v=9JDGmzZaMkE&feature=emb_title (https://www.youtube.com/watch?v=9JDGmzZaMkE&feature=emb_title)

2) A forum thread with a sample scene and renders:
https://forum.corona-renderer.com/index.php?topic=18936.0

I always assumed that was how it was supposed to work, but when I set the projection mode (screen/enviro) the hdri i'm using is visible on the shadowcatcher plane. it also seems to project/reflect light upwards underneath the object...?