Making hair color references more useful

[LiamTub]

I am preparing a portrait comparison for an online group discussion about possible hair color changes. I would like useful comments on the shades, with as little distraction from the layout as possible. Every version will use the same framing, since different crops could distract people from the actual color change. While looking into a hair color simulator I started making a checklist of the settings that should stay consistent. The background should remain unchanged, and I do not want separate brightness adjustments for individual versions. Numbering the alternatives might encourage more specific observations than presenting them with attractive color names from the start. I will explain that the images are discussion aids and cannot show exactly how real coloring would turn out. After the first comments, I can add the labels and ask whether anyone wants to revise their description. Which other presentation details might distort this kind of side-by-side hair color comparison?