New Post: Photoshop high pass filter

Hi,

I try to rebuild a Photoshop high pass filter using ImageMagick convolve.

From the ImageMagick documentation, I got the following:
convert face.png -bias 50% -morphology Convolve DoG:0,0,2 face_dog_unity.png

I tried the following in magick.net:
image.Morphology(MorphologyMethod.Convolve, Kernel.DoG, "0,0,2");

What is missing is the -bias. How can I achieve the filter?

Thanks for your help
Lemon