You can click “select your monitor dimension” to resize the ruler. The default they gave me was wrong. I actually suggest making the ruler even smaller than the authentic size, so that the distance between millimeters will be shorter and thus the ratio will be more precise.
First thing I thought was ‘I’m not sure it’s accurately calibrated’, but since we’re measuring ratios it doesn’t matter.
You can click “select your monitor dimension” to resize the ruler. The default they gave me was wrong. I actually suggest making the ruler even smaller than the authentic size, so that the distance between millimeters will be shorter and thus the ratio will be more precise.