Imaging Techniques

Like many multispectral cameras, the Artist Camera uses a filter wheel approach to capture images from different electromagnetic spectrum bands. Seven glass filters are used in the motorised filter wheel placed in front of a 2 or 5 megapixel monochrome CMOS imager. In this way, spectral bands of 300-400 nm (UV), 400-500 nm (blue), 500-600 nm (red), 400-700 nm (visible), 700-1100 nm (IR) and 1000-1100 nm (IR) are captured by the camera.

The different wavelengths captured at UV, visible and IR frequencies provide a wealth of information about the paintings themselves. By illuminating it with a UV light source, UV reflective images can reveal the surface texture of the painting, as the UV light is mainly reflected from the top surface or from the varnish layer often used to cover the paint. Alternatively, if the camera is fitted with a UV blocking filter and UV lighting is used, UV fluorescence measurements will show the distribution of pigments over a painting or object. By comparing colour and fluorescence images, we can visualise where specific retouches are present.

At the other end of the electromagnetic spectrum, captured IR images can reveal information about the painting's underlying paint layers or panel conditions. Colour and IR images can be compared by using the broad spectrum halogen lighting, which has a high IR spectral content.

By illuminating paintings under halogen lighting, the Artist camera can also be used in a false colour IR mode. To achieve this, red, green, blue and IR images are first captured by the camera. Leaving aside the blue component, the green, red, and IR images are combined to form a false-colour composite IR image. This results in an image with extra contrast in which any underdrawings can be more easily visualised.

The combination of high resolution with vision techniques makes the ARTIST the state-of-the-art in non-destructive analysis and documentation of art objects. It offers many advantages over conventional photographic cameras. The high-quality recordings are stored digitally. By seamlessly connecting multiple images using software, recordings of tens of megapixels can be realised.

Applications

The camera has many different options and can be used for both material-technical and cultural-historical research. For example, UV light can be used to make the structure of the paint layer and old retouches visible. In addition, it is possible to apply infrared lighting. This allows the underlying layers of paint or the carrier to be unlocked. Infrared can also be applied in false colour mode. This creates an image with non-natural colours that allow specific contrasts to be perceived.

Non-destructive Analysis 

The techniques below can be used for the (preliminary) investigation, the determination of damage and the documentation of artefacts:

VIS (Visible Photography front (VIS) and Back (BCK)) - Displays the current images of a painting and will serve as a basis for comparison for the other Multispectral images.
Scattered Light - Accurately documents crazing, loss of pictorial layer and offers insights into painting technique, such as brush marks and instruments used.
UVF (Ultraviolet Fluorescence) - Identifies old and new layers of varnish and thus makes it possible to distinguish the original surfaces of the retouches (Artist Camera).
UVR (Ultraviolet Reflected) - Maps faded inks and prints (Artist Camera).
IRFC (Infrared False Colour) - This allows to estimate the relative amount of retouches (Artist Camera).
IR Image (Infrared Image) - Can reveal information about the painting's underlying paint layers or panel conditions. By using broad-spectrum halogen lighting, which has a high IR spectral content, colour and IR images can be compared.
High-resolution images/Museum digitisation - Thanks to our partner, we can offer you the digitisation of 2D and 3D in all resolutions up to extremely high. Paintings can be shot almost anywhere, even if a painting is hanging very high.
The great advantage of an extreme resolution is that you can do everything with it, from a strong partial magnification without loss of sharpness to looking around a painting through a video film.