Good evening, and thanks for the quick reply. I tried removing the Normalize node as you suggested. You are correct that is isn't needed, but removing it actually made the problem with previews worse. Now the Noise node's direct output is the only thing I can preview. Even the output of the Raw Input, which was working before, has stopped working. There are zero messages at any severity level in the console. Closing and restarting Unity didn't help; I tried that just for "due diligence" after making the node change. For reference, this is in Unity Pro 2018.3.12.