The Spectroline Bi-O-Vision series two-in-one transilluminators manufactured by Spectronics Corp. feature two workstations, producing both 312-nm UV and white light. The TD-1000R model offers fixed-intensity, while the TVD-1000R offers variable-intensity control of either UV or white light. The units are continuously adjustable from 100% down to 50%, enabling life sciences researchers to select the exact UV or white-light illumination needed to photodocument samples with a single piece of equipment. The UV-B (312 nm) intensity can be varied without preset stops, from 6000 to 3000 μW/cm2, and the white light output can be adjusted from 2000 to 1000 fc (186 to 93 lx). This flexibility in irradiance control ensures long sample preparation time.