Raising the eyebrows gets the forehead to wrinkle and this shows the anatomy of the muscles under the skin. The distances between the Glabella (the bridge of the nose) and the highest wrinkle on the forehead tells me a great deal when measuring the leading edge of the hairline. A normal mature hairline is usually one finger breadth distance between the highest wrinkle and the midline hairline. A picture of your entire face allows me to judge general proportions, chin to nose, nose to Glabella and Glabella to hairline. Michaelangelo in his status of David, put the proportions of these distances 1/3rd, 1/3rd, and 1/3rd however most normal people find that the distance between the chin and the tip of the nose is equal to the distance between the Glabella and the leading edge of the midline hairline.