Infrared: Norway 2009-06-02

Impressions in infrared from my archive of travel photographs:

Lysefjord. NRG infrared photograph, i.e. the infrared image is encoded in the red channel, whereas green and blue channels contain the red and green channels of the image in the visible spectrum (see
here, 'false-colour'). Vegetation appears red and can be differentiated against the rocks. There is still snow on the mountains at the horizon.

view of the North Sea in the direction of Stavanger, pseudocolor-infrared photograph (clear despite haze)

Myrdal station, black and white infrared photograph
Young beech foliage and snowfiels have strong near-infrared reflectivity.

Infrared: Turin 2010-05-29

view of central Turin with the Mole Antonelliana (720 nm low-pass filter)
Construction of the Mole Antonelliana (image center, 168 m high) started 1863 as a synagogue, but as the construction cost was steadily increasing, the Jewish community withdrew from the project which was finally finished in 1889, after the city has token over it. Today, the building accomodates a Museum of Cinema.
At the horizon you can see the mountains of the Alps, which are - in contrast to the photograph in the visible spectrum - observable in the infrared image as infrared radiation is less scattered by haze than visible light.

Infrared: Bebenhausen 2013-11-09

infrared (720 nm low-pass) view of Bebenhausen

false-colour

The greyscale infrared pictures can be used to create colourful false-colour infrared pictures. The infrared picture (ir) is swapped into the red channel (r), whereas the original red and green (g) channels are swapped into the green and blue (b) channels, respectively (the original blue channel is not used):

This corresponds to the analog Kodak EIR false-colour infrared film. Vegetation appears magenta, whereas areas which both reflect red and (near) infrared appear yellow.

Detail from the picture above:
As a result of colour channel swapping (g > b), the roof of the Green Tower appears blue.
In the forest, conifers (magenta) can be discriminated from broad-leafed trees (orange), which either are bare or have red-brownish foliage.

Infrared: Birkensee 2013-10-30

Birkensee, 720 nm low-pass

reflections in the lake

Infrared: Birkensee 2013-08-16

Birkensee in infrared

water lily leaves

alternative processing

In the pictures above, the actual infrared intensity is encoded in the brightness, whereas colours are developed in an aesthetic way.
However, infrared pictures can also be processed using the colours from regular images overlaying them on the infrared brightness, which results in the following images:

Birkensee

water lily leaves on Birkensee

pine trees

the different ways of processing in detail:

The first line shows a normal and an infrared picture. The infrared picture (IR-RAW) obtains its colour because the red pixels are most sensitive to the infrared radiation. The easiest processing is to convert the infrared image into a black and white picture (IR-BW). To get coloured images, one can take the colours (VIS-CL) from the normal image and apply them to the infrared black-and-white picture. This result 1 has natural colours with a brightness derived from the infrared image.
Another way to get coloured infrared pictures (the ones first shown) is to apply white balance on the leaves (IR-WB) and then swapping the red and blue channels of the image (result 2).

further impressions

bog cranberry (Vaccinium oxycoccos)