Change the color of shadow on transparent plane

Hi,

Is it possible to change the color of a shadow on a transparent plane?
See images.

Thanks in advance.



Apenkop op strand2.blend (705 KB)

The color of the shadow of the monkey head need to be more blue, so the color is the same as the color of the real shadows.

Is there really nobody on the forum who can help me? :frowning:

From what I can see in the Compositor, you have the shadow as black on a white background. Invert it and use it to set the Alpha channel on itself. So you’ll get a white shadow on a transparent background. Colorize it with RGB curves (for example) and overlay it on the background image (instead of Multiply).

That’s just an idea like that, from the top of my head. :wink:

EDIT: I just noticed you attached your blend file. I’ll look into it.

If you want to be sure that your scene has the same lighting like REAL world (photo) - you should add HEMI light with blue emission (power 0.2 for HEMI, and SUN with power 1). HEMI light will simulate a light from sky. In real world (when day is sunny and without clouds) all shadows are blue - why? Because in places where sun is unable to emit HIGH ENERGY YELLOW photos (we are talking about shadows area), than blue photos are hitting these areas with low energy blue photos (shadows area). Power of photos from SUN i very high, power of photos from sky is rather low - that reason why in sunny day facades are rather white and yellow with natural colors. Light from sun in winning with ligth from sky:)
Check my blend file. It’s not postproduction way to make blue shadows - rather natural way to make shadows look real.
I hope it’s helpful.
Greetings
Krzysztof Czerwinski

Attachments

Apenkop op strand2_SKY.blend (856 KB)

If you want to be sure that your scene has the same lighting like REAL world (photo) - you should add HEMI light with blue emission (power 0.2 for HEMI, and SUN with power 1). HEMI light will simulate a light from sky. In real world (when day is sunny and without clouds) all shadows are blue - why? Because in places where sun is unable to emit HIGH ENERGY YELLOW photos (we are talking about shadows area), than blue photos are hitting these areas with low energy blue photos (shadows area). Power of photos from SUN i very high, power of photos from sky is rather low - that reason why in sunny day facades are rather white and yellow with natural colors. Light from sun in winning with ligth from sky:)

Attachments

Apenkop op strand2_SKY.blend (856 KB)

Put your shadow plane on it’s own Render Layer. Plug Render Layer’s alpha socket into the top socket of a Mix node set to Multiply. Set the bottom socket of the mix node to whatever shade of blue you need it to be. Plug the result into the image node of a Set Alpha node. Plug the Render Layer’s Alpha socket into the Set Alpha’s alpha socket.

Attachments


Thank you all for your answers!! I’m at work at the moment, so I can’t play around with Blender. I’ll try all of the mentioned ideas/solutions as soon as possible.

Thanks again!!

:slight_smile: