The Micro Fading Tester (MFT) measures temporal behavior of dyes under irradiation.
MFT tests allow to rank objects in collections by their sensitivity to light.
This approach allows to adopt exhibition policies to
actual data obtained for each tested object rather than use
general assumptions which could be either too conservative
and unnecessarily limit viewers access to the object or too optimistic
and lead to irreversible light-induced damages.
The scientific grade instrument is equipped with up to 6 ultra precise LEDs on a motorized holder. One can perform light aging of samples with UV, Vis or NIR LED source and assess the color change with a white LED.
Some users opt for several white LED with different color temperatures, so they can match them to those used in galleries.
Our light calibrator is a mandatory accessory for automatic calibration of light-sources of the MFT.
The most important features of the instrument
- Spot diameter: 0.5 mm
- Spectral range: 400-750 nm
- Spectral resolution: 2.50 nm
- Vertical motion range: -80 to 200 mm
- Light source: up to 6 motorized LEDs
- Focus point search: automatic
- Maximum light intensity at focus: about 4 mW (depends on selected LED)
- PC connectivity: USB 2.0
- Size: 250 x 400 x 440 mm (w x l x h)
- Size when folded: 440 x 400 x 80 mm (w x l x h)
- Mass: 5 kg
The most important functions of the software
- Full control of the instrument: max. light output, intensity of dimmed light for positioning, speed of autofocusing, ..
- Option to record series of reflectance spectra
- Automatic test ending according to the user selected criteria: time, dose or color change
- One button calibration for background and white standard
- Fast high precision autofocusing
- 3 pre-selected light intensity values for quick operations
- % reflectance reading available
- Sample fading can be compared with user generated curves for Blue Wool standards or other samples
- Instant access to colorimetric values with color difference ΔE76 and ΔE2000 according to CIE76 and CIE2000 standards
- Color change displayed on screen
- Automatic generation of reports of a faded sample by a single button
- Automatic radiometric and photometric calibration of the light source with the light calibrator
The MFT allows to measure color change under illumination in a non-destructive way:
(1) the spot of light on a sample has only 0.5 mm in diameter, (2) the total color change (∆E)
for the selected point is constantly monitored during the measurement and the operator
and/or the instrument software could stop the test when ∆E reaches a selected threshold value
(i.e. below reaching the level of just noticeable difference).
In practice, for non-glossy objects fading marks are never visible unless fading was performed
to reach extreme ∆E values (>15).
The micro fading tests could be performed for nearly all classes of materials found in
museum collections, and is particularly suited to study fugitive objects (works on paper –
manuscripts, prints, watercolors; canvas paintings; textiles). Some classes of objects cannot
be tested by the MFT method or their testing is difficult to perform or to interpret obtained
results – objects of a very high light stability and objects interacting with light in an non-typi-
cal manner (highly reflective or transparent). The MFT instrument could be regarded as
portable and so it could be moved within the museum to the objects’ location,
which is particularly important in case of large artefacts (e.g. wall paintings, sculptures, maps)
or objects of significant value.
So far the following institutions have purchased the MFT:
- Qatar National Library Doha, Qatar
- Gothenburg University Gothenburg, Sweden
- Academy of Fine Arts Warsaw, Poland
- Center for Research on Preservation CNRS Paris, France
- National Museum Oslo, Norway
- Conservation Centre Vejle, Denmark
- Library of Congress Washington DC, USA
- Science Museum London/Swindon, UK
- Kunstmuseum Basel Basel, Switzerland
- Bei Jing Jiayuanwenbo Technology Limited Beijing, China
- Tainan Art Museum Tainan, Taiwan
- Silesian Museum Katowice, Poland
- Langelands Museum Rudkøbing, Denmark
- United States Holocaust Memorial Museum Washington DC, USA
- Philadelphia Museum of Art Philadelphia, USA
- National Library of Norway Oslo, Norway
- National Taiwan Museum of Fine Arts Taichung, Taiwan
- Stuttgart State Academy of Art and Design Stuttgart, Germany
- The Museum of Modern Art New York, USA