True, I knew about the vertical line on the outer side of your iris. Some like a more outwardly arch I noticed, and the vertical line then align the outer corner of their eye, so this seems halfway between them (:.

I'm wondering the same thing.

Same, I notice there are different guidelines for various tutorial though most follow generally harmonic proportions for placements. I know about one where eyebrows are made to start between two vertical lines, one from the inside corner of the eye and the outside of your nostrils, for when the two are not aligned, also to make so wide set eyes are balanced with closer eyebrows and close set with further apart ones.