Short answer
Some dyes reflect strongly in the near-infrared, just beyond the red the eye can see. Silicon sensors respond there too, and the infrared-cut filter in front of them does not block it perfectly. A fabric that looks black to you can therefore look purple, maroon or brown to a camera, especially one with a weak filter, under light rich in infrared such as sunlight or halogen. More generally, the camera's sensitivities differ from the eye's, so particular dyes can photograph as a different colour from how they look.
Human vision stops at the red end of the spectrum around 700 nm. Silicon, the material of camera sensors, keeps responding well beyond that into the near-infrared. Cameras put an infrared-cut filter in front of the sensor to block this, but the filter is not perfect: engineering studies of CMOS colour cameras note infrared light from roughly 700 to 1000 nm reaching the sensor through it, and registering in the colour channels — including the blue channel, whose filter often transmits infrared as well as blue. Whatever infrared gets through is added to the colour the camera thinks it saw.
A black dye's job is to absorb visible light; what it does beyond 700 nm is irrelevant to the eye and often not considered by the dye chemist. Some black and navy dyes on synthetic fibres reflect strongly in the near-infrared. Carbon-black pigments, by contrast, absorb there too. When an infrared-reflecting black is photographed, the leaked infrared adds signal to the red and blue channels, and the camera renders a colour you never saw — typically purple or magenta, sometimes brown. Two black garments that match perfectly by eye can photograph as different colours for this reason.
The same mechanism is why remote-control LEDs show up as a violet glow on many phone cameras.
Infrared is the dramatic case, but not the only one. Within the visible range, dyed fabrics have reflectance curves with peaks and troughs that the camera's red, green and blue filters weight differently from the eye's cones. Some blues photograph purple, some greens photograph blue, and certain bright synthetic colours land outside what the camera's colour matrix handles well. This is camera metamerism, and it is specific to the dye, the camera and the light: change any one and the effect changes.
Light sources matter most. Sunlight, halogen and incandescent bulbs are rich in infrared; typical white LEDs emit very little, so the infrared problem often disappears under LED studio lights. Cameras with stronger infrared filtering, or an added infrared-blocking filter on the lens, reduce it further. For garments where colour matters, check a test shot against the real item under the same light before a full shoot, and correct any remaining shift selectively in editing rather than with a global change. Sheen, clipping, moiré and coloured stage light, which also change how outfits photograph, are covered on the fashion photography page.
Why: The dye reflects near-infrared, which leaks through the camera's IR-cut filter in sunlight.
Fix: Correct the garment selectively in editing, or use a lens-mounted IR-blocking filter for future shoots.
Why: One dye reflects infrared and one absorbs it.
Fix: Photograph them under LED light and check a test frame before the shoot.
Each statement is labelled by kind — established fact, a standard’s requirement, observed market data, a convention, or Colourwise’s own interpretation or analysis — with the strength of the evidence behind it.
FactModerate evidence
Silicon CMOS colour cameras can register near-infrared light from about 700 to 1000 nm because infrared-cut filters are imperfect, and this infrared signal appears in the colour channels.
FactStrong evidence
Camera spectral sensitivities differ from the eye's, so dyed materials can be recorded as different colours from how they appear, depending on the dye, camera and light.
Colourwise interpretationLimited evidence
Some black and navy textiles that reflect near-infrared photograph as purple, maroon or brown on cameras with incomplete infrared blocking, especially under infrared-rich light.
Based on: Follows from infrared leakage through imperfect IR-cut filters (cited) combined with the known variation of dye reflectance beyond 700 nm; no controlled study of garments was located.
Caveat: Which fabrics are affected depends on the specific dye; many black fabrics photograph correctly.
FactModerate evidence
White LEDs emit little near-infrared compared with incandescent and halogen lamps, which reduces infrared-driven colour shifts in photographs.
Source: LED Basics
Reviewed 29 September 2026. Colourwise summarises its sources in its own words and does not reproduce standards text or proprietary colour data. Spotted an error? Tell us.