Chaos Corona Forum

Chaos Corona for Cinema 4D => [C4D] I need help! => Topic started by: 3dkobi on 2019-05-06, 07:52:13

Title: Transparent background ?
Post by: 3dkobi on 2019-05-06, 07:52:13

Hi,

I need to produce for my client several images like the example attached, and the white background should be transparent (PNG file).
I put the ship on a white shiny plane in order to get the reflections, but now I can't find a way to tell corona to render this as transparent...
Of course I can do this in PS, but a solution inside corona will be better :)

Peace,
Kobi

Title: Re: Transparent background ?
Post by: romullus on 2019-05-06, 10:44:28

I had similar task a while ago and found that easiest way is to mirror copy of the object on its vertical axis, render image with separate masks for both objects and then add transparency and "reflection" fading in photoshop :] Worked well enough for me.

Title: Re: Transparent background ?
Post by: 3dkobi on 2019-05-06, 10:49:17

Cheers, sounds like a good work-around

Title: Re: Transparent background ?
Post by: FrostKiwi on 2019-05-06, 13:36:53

Quote from: 3dkobi on 2019-05-06, 10:49:17

Cheers, sounds like a good work-around

No need for Photoshop trickery.

Quote from: 3dkobi on 2019-05-06, 07:52:13

I put the ship on a white shiny plane in order to get the reflections, but now I can't find a way to tell corona to render this as transparent...

The Corona ShadowCatcher is exactly made for this purpose. Though I'm on 3dsMax, I'm sure it's the same for C4D.
See Image attached.
1. ShadowMatte with reflection turned on
2. Enabled Alpha Mode "For Compositing"
3. Alpha now renders reflection
4. Reflection correctly now overlays over anything

Title: Re: Transparent background ?
Post by: 3dkobi on 2019-05-06, 14:49:09

Thanks, I'll check this function

Title: Re: Transparent background ?
Post by: maru on 2019-05-16, 15:15:00

Remember to render against a black background. Otherwise you will end up with white borders around your objects.