The used Camag Table UV-lamp can emit wavelengths of 254 and 366 nm. It is mainly used for the inspection of TLC plates.
Long-wave UV light 366 nm
Under long-wave UV light substances that can be excited to fluoresce appear as bright spots, often differently colored, on a dark background. The sensitivity of this detection method increases with the intensity of the UV light and also as more visible light is eliminated.
Short-wave UV light 254 nm
Under 254 nm UV substances absorbing at that wavelength become visible, provided the chromatogram layer contains a fluorescent indicator, e.g. F254. These substances appear as dark spots on a bright background (fluorescence quenching).