What is it and what can you learn from it?
The ‘curtain viewer’ is an interactive app that allows you to better examine images of every wavelength made of paintings and other art works. It is a powerful tool for art historians and conservators, but also for art lovers who want to fathom a work further.
What exactly can you find out through the app?
The app allows you to view paintings in original, full-spectrum, high-resolution images combined with ultraviolet light, infrared photography, infrared reflectography, X-ray images, and so on. The possibilities are endless.
Each wavelength provides different information about the condition, materials used, technique and structure of the work. More about which wavelength gives which result can be found here:
VIS_BT (Visible Photography Before Treatment); VIS_AT (Visible Photography After Treatment). shows the images of a painting before and after restoration and will serve as a basis of comparison for all other multispectral images.
RAK (Raking Light Photography) meticulously documents craquelures, loss of pictorial layer and provides insights into the painting technique, such as brush strokes and instruments used.
UVF (Ultraviolet Fluorescence Photography) identifies old and new layers of varnish and allows the original surfaces to be distinguished from retouching.
IR (Infrared Photography), up to approx. 950 nm, provides a first picture of the underdrawing and structure of the painting.
IRR (Infrared Reflectography), up to approx. 1700 nm, provides an extremely detailed image of the underdrawing, i.e. the drawing made by the painter before he or her started painting.
XRR (X-Ray Radiography) is a classic X-ray image that gives an insight into the internal structure of a painting as well as the distribution of lead-based paints.
MACRO-XRF (macro X-ray fluorescence): is an analysis technique that uses X-ray fluorescence spectroscopy to scan a defined area on an art object in the X and Y axes. This non-destructive method reproduces the distribution of the chemical elements in a 2-dimensional image. The Macro-XRF method is extremely suitable for the study of historical paintings and other visual art objects, because it can reveal hidden layers of paint, changes made by the painter or old restorations through the distribution of chemical elements. It also provides a unique insight into the creative process of the artist.
How do you use it?
The different images can be viewed individually by clicking on the different images under the “VIEWS” column, or across multiple imaging modes simultaneously with the viewers by clicking the “Sync” button under the “MODES” column. Zooming in is done by the scroll-wheel on the mouse, click and drag to move the view. On touchscreen devices, the imaging windows can be moved by touching and dragging an individual image.
The “Curtain” mode allows a dynamic splitting of the view into panes that constantly resize to follow the mouse pointer. In this mode a maximum of three images can be combined.