What’s happening
Plants reflect near-infrared light strongly, just beyond the red your eyes can see. A clear sky and water reflect very little of it. An infrared filter blocks most or all visible light and passes the near-infrared, so the sensor records foliage as bright and sky as dark.
Choosing a filter wavelength
| Filter | Look |
|---|---|
| ~590 nm | “Super colour”: some visible red passes, so colour can be swapped in editing |
| 665–720 nm | “Classic” infrared: glowing foliage, dark sky, still some tonal range |
| 830–850 nm | “Deep” infrared: nearly pure IR, the most dramatic, the longest exposures |
Why a monochrome sensor
A camera like the Leica M11 Monochrom has no colour filter array, so infrared lands as clean tonal values rather than being spread across a Bayer pattern. It’s the camera behind the infrared work on this site. On a colour camera, most sensors carry an IR-blocking filter, which is why they need very long exposures, or a conversion.
Shooting it
- Wait for bright sun. Foliage reflects the most infrared in clear midday light — the opposite of ordinary golden-hour advice.
- Use a tripod, compose and focus first with no filter on (a dark IR filter is nearly opaque), then attach it.
- Stop down to f/8–f/11. Infrared focuses on a slightly different plane than visible light; depth of field covers the difference.
- Expect to lose several stops. Meter through the filter if your camera allows it; otherwise start around four stops longer and read the histogram.
- Shoot RAW.
Editing
Convert to black-and-white and build contrast with a curve; dodge and burn to separate foliage from sky. On a colour camera, a channel swap (red and blue) gives the classic false-colour look.