The instructions for shooting the calibration target on the screen state:
"Make a shot of the calibration target on the screen (make sure it fills the whole frame, avoid reflections, glare, etc.) or on paper"
None of the provided calibration target sizes exactly fit my screen so I will either have a border showing my desktop color or I will be missing part of the calibration target.
Use "fit to window" function in your image viewer. This will stretch the Target to fill the whole screen area. The most important is to fill the whole frame and to not leave out any of the squares.
