Fig. 5

Spectral-SIM processing of dual excitation-channel (488 nm and 561 nm) image. Raw images were taken from a caudal trunk of Tg(kdrl:GFP; fli1a:Gal4; UAS:nfsB-mCherry) triple transgenic fish (ventral right, dorsal left). GFP and mCherry were co-expressed in vascular endothelial cells. The SIM pattern period was 14 μm. 11 step exposures were used. Scale bar: 20 μm. (a) Reconstructed zero-order component image, IFFT [R̃′₀(k_x, k_y)]. contains both in-focus ballistic signals and out-of-focus and scattered signals. (b) The absolute value of the complex image, IFFT [R̃′₁(k_x, k_y)], is background free. (c) The phase value of the complex image, IFFT [R̃′₁(k_x, k_y)], encodes the sources of excitation. The arrow points to an area with a phase different from the majority of the map. (d) The dual excitation image represented in pseudo colors (green: emission from 488 nm laser, mainly emitted by GFP; red: emission from 561 nm laser, mainly emitted by mCherry). The image was obtained by spectral decoding R_n(x, y). The same area pointed by the arrow has stronger 488nm excitation (stronger GFP expression) than the rest of the image.