Burlap for shading?

[sand_tiger86]

I'm currently using burlap as shadecloth over my setup outside, and it is exactly like the picture except I don't have it doubled over so slightly more sun gets through. Do you think this is too much shading?

edit: I suppose it'd be helpful if I told you what I was growing. Several catts, a vanda, dendrobium, and an angraecum.