>>4310636>https://www.the-digital-picture.com/Help/MTF.aspxBest way to wrap your head around MTF charts is to imagine circles radiating out from the centre of the image. Blurring between those circles, or how much a point of light smears outwards from the centre of the image, is Meridional mtf.
Then imagine the circles had spokes. The blurring between the spokes is your sagittal MTF.
Lateral CA shows up in the meridional measurement, hence why it's normally the lower of the two lines.
