I’ve discovered that many wild vegetables have flowers that become magical when ultraviolet light is used to make them fluoresce. This is a wild onion flower, normally white in visible light but there is a dramatic shift when intense UV light is used!
These images should not be mistaken for what insects see, which is “ultraviolet reflectance”; Such images can reveal hidden patterns that insects perceive but we cannot. My UV fluorescence photography, on the other hand, reveals a view of nature that is impossible to see by any creature on Earth. This image is shot with UV light, but the camera only collects the visible light that fluoresces off the surface, a phenomenon known as UVIVF, or UltraViolet Induced Visible Fluorescence.
Because this requires that the light contain exclusively UV wavelengths and nothing in the visible spectrum to contaminate it, there is no way to “naturally” see this – since the sun will always be putting out a full spectrum of light that we can see directly. I use three flashes for these images, all modified Yongnuo YN685 units. I’ve taken the flash apart to remove the UV-blocking filters, and I’ve placed two 77mm lens filters in front of the flash head with Gaffer’s tape: a Hoya U340 and a MidOpt BP365. Both of these filters block the visible spectrum and allow UV light to pass through, but each leaks a small amount of light at opposite ends of the visible spectrum. Combined, they make a pretty good combination for UV-only light hitting the subject.
The camera is unmodified – just a plain old standard DSLR collecting visible light. If the subject didn’t fluoresce, the image would be completely black. Everything in nature tends to fluoresce to one degree or another (you make have heard of scorpions or certain millipedes that glow brightly under a black light), but ordinary flowers fluoresce so little that it takes these three flashes at point-blank range, 100% 1:1 output to get enough light to make an image. Even then, I still need to be shooting at ISO 3200 to make this shot work. We’re playing with extremes here!
This image was taken as a full profile of the flowering head, but I found the “magic” was strongest in the details, so this has been cropped in considerably to get the composition you see. It’s also focus stacked, combining 9 frames to get everything sharp from front to back. Focus stacking via my normal “hand-held” means would be incredibly tricky here, as 3-4 seconds have to pass between shots for all of the flashes to completely recycle and be ready for the next image. Because of this, I used a tripod and a focusing rail… one of the few times I’ve been forced to do so! This wasn’t a fancy rail, but rather a $20 one found on eBay with free shipping from Hong Kong.
You’ll notice that the pollen glows quite brightly, where in “regular” light the pollen would be darker (and yellow) compared to the bright white petals. This is a common feature I’ve seen in flowers – glowing pollen. Sunflowers take the crown for the brightest glow, but almost all pollen I’ve studied will glow to some degree. This makes for some very dramatic imagery, like you see here.
While I don’t offer this ultraviolet photography as a group workshop because of the equipment involved, I’ve had a ton of fun with private 1-on-1 ultraviolet workshops. If you’re interested in booking a private workshop to learn how to do this, just send me a message or e-mail me at email@example.com – there is much to explore in the universe at our feet!