Texture Painting Clone Tool not cloning properly

I am trying to use the texture paint cloning tool to cover up a seam. What I am expecting the cloning tool to do is clone the texture exactly, however, I find that it paints it differently on the mesh depending on the viewing angle and on how close I am to the mesh.

In the image below there are 2 objects. I am painting to the object on the right. If the cone tool would work as expected, the texture (UV test grid) on the right object should match up with the texture on the left object along the middle.

I discovered that if I am in ortho view and I paint the texture, it aligns perfectly. Why does this not work in perspective view? Ortho view is very difficult to use - parts of the mesh block areas I am trying to paint. How can I paint in perspective view and get the textures to align?

This is how this tool works. 3D Painting tools work differently from 2D painting tools. you viewing angle, distance matters.
The best way to clone is to first choose the spot, which you want to clone, set the brush sizes etc then , just rotate the mesh and start cloning.