Full Spectrum
Full spectrum refers to ultraviolet, visible and infrared light combined – the full range of light within the electromagnetic spectrum.
Filters
With the use of filtration we can selectively limit full spectrum sensitivity to specific wavelengths, rather than requiring separate dedicated ultraviolet or infrared cameras.
With a UV and IR blocking filter called a hot-mirror, a full spectrum camera can be used as a ‘normal’ camera too.
Applications
Full spectrum is usually used in conjunction with filters to shoot in ultraviolet or infrared.
WIthout filters however, full spectrum is ideal for low-light filming. Output from the sun is two-thirds infrared, meaning exposures are about 1-2 stops brighter than normal when shooting outside, even well after sunset.
When using infrared lighting for night vision applications, there’s no need to use filters either as there’s little to no visible light to block.
FAQ
What is full spectrum?
Full spectrum refers to the range of wavelengths either side of and including visible light, from ultraviolet at around 250nm through to infrared up to >1000nm.
What can you use full spectrum for?
As full spectrum includes infrared in addition to visible light, it can be used for low-light filming. Most of the sun’s light is infrared, meaning an exposure in full spectrum is several stops brighter than just visible light.
Using filters, full spectrum cameras can be used to selectively view and capture ultraviolet and infrared images. With the right filter (called a hot mirror), it can even be ‘converted’ back to regular visible light.
What does full spectrum look like?
Depending on the amount of infrared light in the scene and the selected white balance, a full spectrum image will have a reddish or purple colour cast to it.
This can be used to creative effect, or for low-light applications this could be suppressed in the colour grade or the whole image converted to black and white for a night vision look.