Apparatus and methods may provide for determining a value of chemical parameter. One or more light emitters may be positioned within a housing to emit light through an aperture of the housing. The emitted light may illuminate a color area of a structure that is separable from the housing, such as a test strip, a printed color reference, and so on. A color sensor may be positioned within the housing to capture reflected light and to convert the reflected light to an initial digitized color space that may be usable to determine a color shade of a color area. The reflected light may, for example, be captured independently at least of a dimension (e.g., predetermined size, shape, etc.) of the color area.