High-Pass Filter an Image

I am trying to replicate an image filter used in another work. The author's describe it as:

"All images exhibited a slight intensity gradient and vignetting. To remove these low-frequency patterns, we applied a high-pass filter with a cutoff frequency of (150/1136)π."

I have been struggling all afternoon to figure out an easy way to replicate this in Matlab given only the above information. I (admittedly) do not have any background in image processing, and have no idea how a value like (150/1136)π applies to a function like imfilter or butter.

This is only a small part of my current work, but seems to lead to a bottomless pit of required background knowledge. I would be eternally grateful if someone here could supply a code snippet or example of how a simple 2D high- or low-pass filter can be constructed for an image given just the cutoff frequency.