HI. I am rendering a few scenes to place into PowerPoint. The images are png with transparent backgrounds, and I am using a shadow catcher. But somehow, I get some outer area on a lighter grey as a falloff. This does not allow me to place the render on a background since I can still see the limits of my render due to this framed shadow.
I need to “merge” the png seamlessly onto the background. I know I could use Photoshop to mask that, but I wonder if this is the correct behavior or if I am missing how to set it in Blender.
I think this might be color bleeding from the cylinder. Try using a glossy shader for the floor, with high roughness so that it almost resembles a diffuse shader
I have an hdri and an area light. The area light is facing the z axis.
Is there any way to turn off the shadow generated by the hdri to verify is the hdri creating those shadows?
Sorry, I misread your question. There may be a node setup for the World in the Shader Editor that can achieve that, but I’m not familiar with it. But it might be worth reconsidering the need for an HDRI for the lighting of this scene. I think you can achieve this with a simple white Background with a low Surface Strength like .100. You’ll get fill light on the object, but the only shadow will be the one cast by the area light.
Thank you! Not exactly about the hdri. I tried now with and without it, and I can say the lighting of the hdri, although not contrasty, gives a lot of depth to the image. There are a lot of subtle reflections in my scene. Be aware the cylinder is a test sample for the forum. I can not post the scene due to NDA reasons.
In that case I think a 2 layer composite is what you need. Layer 1 being the object only, full lighting setup; layer 2 the shadow catcher only, object set to holdout or invisible to camera, HDRI strength @ 0.
I meant the size property, sorry. Sun lights have no size, since they’re considered to be infinitely far away. They have an angular size instead.
Basically if you set it to 0 degrees your shadows will be infinitely sharp. Increase it and your shadows will be blurred. I think that’s what’s happening with your area light : consider one end of your area light rectangle (assuming it’s a rectangle), it casts the shadow of the part of the model that’s directly under it, right ? but it also casts the shadow of the opposite part of the object, at a very steep angle, producing very long and blurry shadows in those directions.
