Shader preview window

[james adamson]

Hi all.
The little blue box you click to preview the shader's texture sometimes shows all black or all white but then the resulting effect on the image does not reflect
that which means sometimes I am flying blind with my texture until I preview it in the full preview, which is a very slow process.
What am I doing wrong and how can I more efficiently and consistently get a 2d preview of my texture?
Cheers.
James.

[Dune]

That could happen if your shader is masked by a distribution off zero, or way off 0/0/0, e.g. It reflects the state at Y=0, and the area around the pole, afaik. I sometimes take undo the masking just to check.

[james adamson]

Weird I have no masks. What I do have is an imported camera could that be the culprit?