Category: Pages
Published: Saturday, 16 March 2019 10:55

Ultraviolet Fluorescence

Ultraviolet light (UV) is invisible to the human eye but when certain substances are exposed to it, they emit visible light. I became interested in photographing fluorescence when a friend told me that scorpions are blue under UV light.  People rarely see scorpions because they are well camouflaged but where I live on the outskirts of Sydney they are quite common and are easy to find if you search the leaf litter at night using a UV light.

My initial photos were disappointing because the backgrounds looked artificially coloured. I discovered that most ultraviolet sources, also emit visible light and most cameras  record this light and also reflected UV light as unwanted colour. High output flashlights such as the ones below can be purchased online for around AU$50 (2023). They emit 365 nm ultraviolet light and include a 'ZBW' filter to block visible light. A "UV(0)" filter can also be used on the camera lens to prevent reflected UV from reaching the camera sensor and producing false colours.


 UV flashlights



Lichen growing on sandstone 


Diamonds - visible and UV light


Marbled Scorpion - UV exposure for 6 seconds at f16 and fill flash. Nikon D750, 180mm lens with UV0 filter, extension tube and tripod


Feathers - Feathers of a fledgling Powerful owl and a Sulphur-crested Cockatoo - visible and UV



 Australian $5 note - visible and UV


Eggs - visible and UV



 Dahlia flowers - visible and UV