Question on how to match color on drop test kit

[simsjim]

I find it helpful to have a white background when looking from the side, to get a better idea of the nuances of the colors. Just a thought

[shadowman]

I wish there was a more precise way of measuring these things. My Cl reading never agrees with the pool store (they are lower) and the only difference is their machine is reading the color instead of a human eyeball. I only go there for a sanity check a few times a season and to check CYA which my kit won't do. Wouldn't it be great if we could just push a button and get a printout?