In preparation of my next dive trip I stumbled across Nightsea, a company dedicated to fluorescent photography, which can be quite amazing at night. Fluorescence is present during the day but usually disappears as it is overpowered by the ambient light present. Check out some of the images! Of course not everyone likes night diving, so sometimes it is hard to find a buddy, and obviously it comes with its own challenges and perils. It is however possible to take fluorescent images during the day. Charles Mazel (founder of NightSea) published an interesting paper in Limnology & Oceanography: Methods in 2005 outlining this. The principle is to excite the fluorescence with UV light (blue filter in front of the strobe), restricting the light to less than 470 nm wavelength, and to take the photo with a yellow filter, which passes light over 500 nm. Furthermore, the shutter speed should be kept at ~ 1/500, reducing ambient light to the point of taking an almost completely dark photo if no flash is used. Thus, (almost) all what is recorded if the fluorescence of the object (plus a minute amount of blue light). This is a simple and pretty ingenious method.
Now I am not in the Caribbean yet and the lakes here are still frozen (nor do I fancy diving in the ocean with temperatures outside around freezing), but you can have plenty fun around the house, as there are many things that fluoresce – be warned, that includes dirt specks!
Photos after the break
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