Fig. 3.

Typical (a) F _q′/F _m′ and (b) temperature images of an A. thaliana plant illustrating the production of (c) CO₂ assimilation (A), (d) stomatal conductance (g _s), and (e) intrinsic WUE (IWUE_i) images. Calibrations were applied to convert pixel values within each image into A and g _s data, respectively. The wet and dry temperature standards used in the calculation of g _s are indicated by arrows on the temperature image. To produce an image of WUE_i (A/g _s=IWUE_i), the A image was rotated, scaled, and interpolated onto the image of g _s. The colour bar beneath each image shows the range of parameter values. For further details of this process, see Materials and methods.