This is a Tobias TB+ film transmission densitometer in very good condition. Fully tested and everything works as intended. Tobias TB+ Transmission Densitometer. The lamps function as does the null function and the density reading function. The cord is included and is supple with no cracks or damage. The densitometer is easy to use. Measurements are made on a push and read basis. The display consists of large LED numerals which can be read easily in bright or dim light. Internal memory and the null button allow the operator to make comparative density measurements across a piece of film. Features include: Lighted Table, Simple calibration procedure Rugged construction. Proven oil field use. Measuring range: 0-5.0D with 2 and 3mm apertures; 0-4.0D with 1mm aperture Scale factor (slope) stability: ±1% per 6 months. Voltage and temperature compensation provides drift-free operation. Modular construction allows rapid replacement of lamps and easy access to electronic circuits. Remains in proper alignment even if it is picked up by the arm. This unit features push button nulling and will compute density comparisons and subtractions. Auctiva offers Free Image Hosting and Editing. Auctiva gets you noticed! Track Page Views With.