This option enables to select one of 4 colors – red, green, blue or white – for film or transmission measurement. This may be very helpful in one of the most common tasks while measuring the density of stained films, e.g. developed by Pyrogallol, Finol or Tanol.
The mentioned option enables to measure the visual density by using white or green light as well as the stain density by switching to blue light.

For details please refer to
http://unblinkingeye.com/Articles/PCat/pcat.html

http://www.moersch-photochemie.de/files/articles/TanolundCo-eng.pdf

Further on that option might be very helpful in technical and biometrical applications where the density measurement in a dominant wavelength range is required..

Densitometer

By means of precise measurement of the optical density, the exposure and development of film and paper can quickly be optimized.

Additionally, the monitoring of technical processes of transparent materials is very easy since thickness and optical density correlate. Measurements up to 6 logD (<1/1000000 transmittance) can be reliably determined with special models of our devices.

Devices by Heiland electronic usually work monochromatically within the visual spectrum and can be individually adjusted according to their task.

Type TRD 2

This device enables density measurement of films and papers and its basic version is already suitable for all typical measurements in black-and-white photography. The following options can be ordered additionally:

• Exchangeable apertures
• USB-port
• Extended measuring range 5.5 logD for transmittance
• Higher display resolution 0.001 logD

An overview of the benefits

• The quality of your negatives will be greatly improved by targeted corrections of exposure and development
• Any film-developer combination will be optimized quickly and safely
• Examination of materials and processes is also possible during enlargement
• Calibration of monochromatic inkjet printers for FineArt prints
• Precise and long-term stable measurements due to solid metal construction
• Low base price due to a modular equipment concept
• Optional device configuration allows adjustment for a large variety of tasks
• Compact design – also ideal for mobile use

Set of 4 exchangable apertures.

0.5mm, 1mm, 2mm, 3mm.

Densitometer

By means of precise measurement of the optical density, the exposure and development of film and paper can quickly be optimized.

Additionally, the monitoring of technical processes of transparent materials is very easy since thickness and optical density correlate. Measurements up to 6 logD (<1/1000000 transmittance) can be reliably determined with special models of our devices.

Devices by Heiland electronic usually work monochromatically within the visual spectrum and can be individually adjusted according to their task.

Type TRD Z

This device is especially suitable for application within the zone system. Due to an alternative display you can quickly and reliably determine the zone value of parts of an image. When assessing the tonal values of negatives there is also the possibility of considering development categories from N-2 to N+2. The following options can be ordered additionally:

• Exchangeable apertures
• USB-port
• Extended measuring range 5.5 logD for transmittance
• Higher display resolution 0.001 logD

An overview of the benefits

• The quality of your negatives will be greatly improved by targeted corrections of exposure and development
• Any film-developer combination will be optimized quickly and safely
• Examination of materials and processes is also possible during enlargement
• Calibration of monochromatic inkjet printers for FineArt prints
• Precise and long-term stable measurements due to solid metal construction
• Low base price due to a modular equipment concept
• Optional device configuration allows adjustment for a large variety of tasks
• Compact design – also ideal for mobile use