Fig. 4

Concurrent transmitted light images were improved by non-absorbed lasers. In thicker and more absorbing samples, transmitted light images were optimised using non-absorbing wavelengths. a Arabidopsis leaf expressing plastid-targeted GFP. b Green pepper pericarp section. c Red pepper pericarp section. Fluorescence images show chlorophyll (red) and either YFP (a) or a combination of carotenoid and cuticle autofluorescence (b, c) (green). Transmitted light images were recorded with 488 nm blue light which was absorbed strongly by chlorophyll and lycopene (central column) or with 561 nm green light (a, b) or 633 nm red light (c) which were not strongly absorbed. A colour filter was used to remove any transmitted blue light. Scale bars 100 µm