Shadow Catcher in Cycles: "chessboard" pattern seen in that place!

[Pedro_V]

I have to change color of Environment image to A(lpha)=0, so after that background was transparent!

But which is the right node to connect shadow catcher-output?

This is what I found, but “Alpha over” was not working in this: https://cgjam.net/public_html/wp-content/uploads/2017/06/2018/01/nodes.png

[lucas.coutin]

To composite your image, shadow catcher pass is multiplied then CG is added with an alpha over node. Try this tutorial: https://youtu.be/w70dMniat2M

[Pedro_V]

FINALLY! This video was a key!

With this node-tree:

Thank You so much Calandro and Lucas, also this Blender Daily man!
Thank You Jesus , blessings from !