Fig. 2

A schematic of the imaging chamber for use with the chlorophyll fluorescence imaging setup. Sections of leaf material are placed atop dampened packing sponge using a thin glass plate affixed using rubber bands (a). Gases are fed into a chamber below the sponge and forced through a perforated Perspex separator for even distribution. A tube located in the upper section samples the gases at leaf level to determine the concentrations of oxygen and carbon dioxide. The chamber is designed to sit as one of four chambers under the camera (b) allowing the user more flexibility with measurements; either treating each chamber as a separate experiment with separate gas concentrations for screening the response of ~ 25–30 leaf sections or for screening the response of 100–150 sections under singular gas concentrations in one measuring session