Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] I need help! => Topic started by: F13Design on 2018-12-10, 20:39:19

Title: Creating shadows for .png extension
Post by: F13Design on 2018-12-10, 20:39:19
So My client has asked me if there is a way to add shadows to a .png file. This is my challenge. Everything is modeled in the space I have this piece of furniture in, so the client has asked me to hide the 3d environment, which I did. I hid it from the camera but uses the hidden geometry to for reflections. So now they are asking if there is a way to add shadows underneath the object and still have a .png file so that they can place the image into another background but to have the shadow with it. See attachment. If any one has a solution that would be great. Thank you for your time.

Best,
Mike
Title: Re: Creating shadows for .png extension
Post by: sprayer on 2018-12-10, 21:05:55
Did you tried to apply shadowcatcher to the floor with black backplate and compositing mode, so you will have alpha for shadows?
Title: Re: Creating shadows for .png extension
Post by: F13Design on 2018-12-10, 22:19:17
Thanks Sprayer! I will give that a try.
Title: Re: Creating shadows for .png extension
Post by: Gewiz90 on 2018-12-11, 03:57:19
Quote from: sprayer on 2018-12-10, 21:05:55
Did you tried to apply shadowcatcher to the floor with black backplate and compositing mode, so you will have alpha for shadows?

Hey sprayer, can you explain how to do that for a more beginner user please?
Title: Re: Creating shadows for .png extension
Post by: F13Design on 2018-12-11, 04:01:03
Sprayer,
I attempted to set the carpet as shadow catcher with back plate being black, as you suggested. See attached image for results. I don't think it rendered correctly. Also see the original rendering where the piece of furniture was rendered in a room all modeled. Is there something I'm not understanding about the shadow catcher. The only thing I can find online as well as your suggestion was using it in with a HDRI. Thanks!

Best,
Mike
Title: Re: Creating shadows for .png extension
Post by: sprayer on 2018-12-11, 07:37:18
You need from that shadowcatcher not a beauty pass but alpha channel what you may use as mask for shadows in composing software or photoshop. You already have render image what you need, so you can hide environment or exclude from rendering, just keep table and the floor with shadow catcher, you may also check direct visibility override to black(black background is need also to render mask without white borders)
so you will have like this, if shadows too bright or too big, you may adjust their levels in photoshop
http://imagizer.imageshack.com/img923/2047/bU4WNs.jpg
http://imagizer.imageshack.com/img923/6856/wr9rkc.jpg
http://imagizer.imageshack.com/img923/2162/Rdxrd5.jpg
Title: Re: Creating shadows for .png extension
Post by: Gewiz90 on 2018-12-12, 01:28:33
Can anyone help with how to control the shadows in post (photoshop)?
Title: Re: Creating shadows for .png extension
Post by: F13Design on 2018-12-12, 03:16:37
Quote from: sprayer on 2018-12-11, 07:37:18
You need from that shadowcatcher not a beauty pass but alpha channel what you may use as mask for shadows in composing software or photoshop. You already have render image what you need, so you can hide environment or exclude from rendering, just keep table and the floor with shadow catcher, you may also check direct visibility override to black(black background is need also to render mask without white borders)
so you will have like this, if shadows too bright or too big, you may adjust their levels in photoshop
http://imagizer.imageshack.com/img923/2047/bU4WNs.jpg
http://imagizer.imageshack.com/img923/6856/wr9rkc.jpg
http://imagizer.imageshack.com/img923/2162/Rdxrd5.jpg


Thanks, Sprayer! I've been quite busy today, so I will try and give this a try tomorrow.
Title: Re: Creating shadows for .png extension
Post by: sprayer on 2018-12-12, 08:00:37
Quote from: Gewiz90 on 2018-12-12, 01:28:33
Can anyone help with how to control the shadows in post (photoshop)?
when you apply mask from corona alpha channel, select that mask thumbnail on layer and hit ctrl+L
https://forums.adobe.com/servlet/JiveServlet/showImage/2-7706664-783707/1.jpg
this level adjustment will be applied to mask only
Title: Re: Creating shadows for .png extension
Post by: F13Design on 2018-12-17, 22:33:04
Quote from: F13Design on 2018-12-12, 03:16:37
Quote from: sprayer on 2018-12-11, 07:37:18
You need from that shadowcatcher not a beauty pass but alpha channel what you may use as mask for shadows in composing software or photoshop. You already have render image what you need, so you can hide environment or exclude from rendering, just keep table and the floor with shadow catcher, you may also check direct visibility override to black(black background is need also to render mask without white borders)
so you will have like this, if shadows too bright or too big, you may adjust their levels in photoshop
http://imagizer.imageshack.com/img923/2047/bU4WNs.jpg
http://imagizer.imageshack.com/img923/6856/wr9rkc.jpg
http://imagizer.imageshack.com/img923/2162/Rdxrd5.jpg

Sprayer, Finally got around to it. Thank you for your help. I got it to work! Much appreciated!

Best,
Mike

Thanks, Sprayer! I've been quite busy today, so I will try and give this a try tomorrow.
Title: Re: Creating shadows for .png extension
Post by: Gewiz90 on 2018-12-18, 01:25:33
What did you end up doing?