Item: 39116
Designed for general photographic calibration of b&w films and variable contrast papers according to the Zone Sytem
Available (allow 10 days for delivery)
login to saveDensitometers are used in film photography to measure densities of negatives and the saturation of prints. Such measurements enable the photographer to choose the right photo paper and the correct exposure instantly, thereby eliminating the need for test strips.
Heiland densitometers are designed and produced by Heiland Electronic GmbH in Wetzlar, Germany, to laboratory standards and are rugged and reliable for all black and white darkroom work.
The design of the TRD-Z densitometer makes it suitable for Zone System applications as it acts as an electronic zone ruler, displaying reflection measurements regarding ten zones between Dmin and Dmax, and transmission measurements in zones according to selected film development. It comes with a fixed 3mm aperture, or interchangeable apertures can be an optional extra.
The TRD-Z can display density in log.D units, or an alternative display 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 quality of your negatives will be greatly improved by targeted corrections of exposure and development when using the TRD-Z. You can optimise any film-developer combination quickly and safely by using it.
Features:
Optional device configuration allows a basic transmission and reflection instrument for everyday photographic applications,
Compact, metal construction design, is also ideal for portable use.
Quick process control for the development of X-ray film and microfilm.
Monochromatic inkjet prints and Fine Art Prints can be calibrated.
You can reliably determine measurements up to 6 logD (<1/1000000 transmittance)
Using the TRD-Z
A small slide switch on the right side of the base is used to select the operating modes - "R" for reflection and "T" for transmission. The "O" (the centre position) is the standby setting that maintains power to keep the unit warmed up and the lamps disabled.
Pressing the arm down on the film turns on the reading light in the base. The density value is displayed in bright red numerals, to 2-decimal precision, in a prominent panel on the front of the arm. A reading accuracy of +/- (1% + 0.02logD), and repeat accuracy is +/-0.01 is guaranteed. The maximum rated transmission density is 3.5, but the instrument will read to 4.0 at 2% accuracy.
Converting the instruments to take reflection readings is just a matter of flipping the selector switch to "R" In that mode, lowering the arm turns on a lamp in the arm itself, and the light is beamed down onto the reading area at a 45-degree angle, a standard arrangement for reflection density readings. The maximum reflection density limit is said to be 2.5, which would be more than sufficient for reading any silver print density. As is the case with transmission readings, the readout is virtually instantaneous. In both operating modes, pressing a red button on the top surface of the arm will zero the instrument; the display flashes "888" when you exceed the measurable reading limit, which is a useful alert that's considerably better than simply providing a false value.
You switch the lamp on when the arm is depressed halfway making it easy to identify the reading area visually, at least for reflection and medium density transmission samples, but positioning heavily dense transmission samples properly over the aperture is still a guessing game.
For zone use, In the reflection measuring mode (print analysis), the range of grey tone values of a print are classified into ten different zones with ten increments each. Pressing the "minimum" button while measuring paper-base white will give a display of zone 10.0. Conversely, reading the lowest reflectance and pressing "maximum" will show a reading of zone 0.0 and is subsequently stored as such. In subsequent measurements within the same picture, it gives the grey tone values in 1/10 zones. In the mid-range of values, for example, a reading could show "zone 5.3" The TRD-Z then serves to replace a visual zone ruler by exact figures, in effect becoming an extremely accurate "electronic zone ruler".
For transmission measuring (negative analysis), it takes the zone system refinement of variable film development into consideration. Separate measuring modes are provided for each of the developing variants: "N" (normal); N +1; N +2; N -1; N -2. The slope of each characteristic curve is taken into account by computer calculation.
The instrument is first nulled by placing an unexposed portion of the negative ("film base plus fog") under the probe and pressing the ""minimum"" button. The display will show zone ""0.0"". Now for example, if an area with a density of log 1.02 above basic fog is measured and if the processing category "N" is selected, the displayed zone would be 6.0. For the other processing categories, the following zone values will be indicated (assuming an equal density):
N+2 = 4.0; N +1 = 5.0; N-1 = 7.0; N -2 = 8.0.
The TRD Z replaces "greytone guessing" with exact measurements. These accurate values then give the user a clear and easy way to appreciate the benefits of the zone system.
Measurements are done about three times in one second, ensuring a continuous reading of even high densities.
There is a lifetime warranty of the lamp and reproducible measurement, and the main body of the units are of solid metal construction.
Additional options for TRD-Z:
- Exchangeable apertures
- USB port
- Measurement range extended to 5.5 logD
- Extended display resolution (0.001 logD)
- Measurement range to extend up to 6.5 logD
- Four colour LED (creates red, blue, green or white transmission light) replaces original white light
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This item is available for collection.
