New Post: Photoshop high pass filter

You will need to set the artifact 'convolve:bias'. That is what is being done on the command line.

image.SetArtifact("convolve:bias", "50%");

I should probably also make this available in code a bit easier. I think that adding a new MorphologySettings class for this would be the next wise step instead of adding two new argument to the method (there is also an option called 'convolve:scale').