Where's the Top of My Head?
The camera photographs in a 4:6 ratio, which (usually) fits print sizes 4x6, 8x12, etc. Business cards might use a 4:5, 4:6 or 1:1 (square) ratio. Older style website profiiles use a 4:5 or 4:6 (vertical) ratio while the newer style website profiles are usually 1:1 (square) or 5:4 (horizontal) ratio.
The Rule of Thirds
Another reason I crop this way has to do with “the rule of thirds.” The rule of thirds is applied by aligning a subject with the guide lines and their intersection points, placing the horizon on the top or bottom line, or allowing linear features in the image to flow from section to section. In the case of a headshot, I crop so the eyes are in the upper third of the photo. We have heard this phrase: “The eyes are the windows of the soul”. Our eyes reflect our emotions: joy, anxiety, anger, etc.. I give my clients both crops for print and web and suggest they use the close up for web profiles.
Cropping (4:6 Ratio)
Above are two different crops of the same image. 1) Before: Uncropped at the 4:6 ratio the camera shoots. 2) After: The top of the head is cropped to focus on the eyes and best use of space and "the rule of thirds."
Cropping (1:1 Square Ratio)
This is what profile photos look like on Facebook, Linked In, etc. As you can see in the after image, most of the photo features you, as opposed to that empty space around your head, again following "the rule of thirds."