The present invention provides a system for extension of dynamic range and contrast of a video capture under fluorescence imaging conditions using a single detector. For this purpose, the system (100) comprises of a light engine (107) which sequentially switches between a high-intensity fluorescence excitation light mode (107A), a low-intensity fluorescence excitation light mode (107B) and NIR reflectance light (107C). Correspondingly, a detector (103) captures three data streams—;High Intensity Fluorescence Data (105A), Low Intensity Fluorescence Data (105B) and NIR Reflectance Data (105D). A scene processing unit (105) then processes the three data streams and generate two additional data streams—;a Wide Dynamic Range Fluorescence Data Stream (105C) and an Enhanced Vascular Index Data Stream (105E). The system also uses a Selective Visualization Unit (106) to allow the user to visualize any of five data streams.