Change of color after I join meshes with Ctrl+J I've made a vase which has 2 handles. The handles were created separately so I wanted to join them and used CtrlJ to do so, with the intention to then trim the unneeded vertexes.

But as I join all in a single mesh there's a change in color, like it's no longer being lit properly. What's causing this and how can I fix it?



Left Joined, right not joined
That's a normals problem. You need to flip normals.

Select the whole mesh in edit mode, then go to mesh, normals, and recalculate outside.

Refer to this: