2021年10月3日星期日

infra-, infra dig, thermographic, an infrared reflectogram of the painting

‘While studying Vincent van Gogh’s Horse Chestnut Tree in Blossom, I spotted charcoal lines between the brushstrokes. I wanted to find out more!’, says Oda van Maanen, restorer at the Van Gogh Museum. ‘I ideally wanted to look under the paint. And that is fortunately possible, using infrared. I asked our photographer Heleen van Driel to make an infrared reflectogram of the painting. This method sometimes makes it easier to see underdrawings. And it worked! Before he started painting, Van Gogh first sketched the tree in charcoal. I also discovered the lines of a perspective frame. Studying the artworks helps me to take the best possible care of them. You sometimes need advanced devices and techniques. And then we work with researchers from outside of the museum, such as our Partner in Science ASML . This helps us to take even better care of the collection, so that many more generations can enjoy it!’ #VanGoghMuseumStaffStories

A thermographic device checks the temperatures of travelers at the quarantine station at Kansai International Airport in Izumisano, Osaka Prefecture.(YASUHIRO MANBU/ THE ASAHI SHIMBUM)

A thermographic camera, sometimes called a FLIR (Forward Looking InfraRed), or an infrared camera less specifically, is a device that forms an image using infrared radiation, similar to a common camera that forms an image using visible light. Instead of the 450–750 nanometer range of the visible light camera, infrared cameras operate in wavelengths as long as 14,000 nm (14 µm).

Image of a small dog taken in mid-infrared ("thermal") light (false-color)

thermographic

thermo+graphic

infra-

pref.
Inferior to, below, or beneath: infrasonic.

[From Latin īnfrā, below.]