From The Secret Lives of Color by Kassia St. Clair:
“In 1666, the same year that the Great Fire of London consumed the city, a 24-year-old Isaac Newton began experimenting with prisms and beams of sunlight. He used a prism to prize apart a ray of white light to reveal its constituent wavelengths. This was not revolutionary in itself — it was something of a parlor trick that had been done many times before. Newton, however, went a step further, and in doing so changed the way we think about color forever: he used another prism to put the wavelengths back together again. Until then it had been assumed that the rainbow that pours out of a prism in the path of a beam of light was created by impurities in the glass. Pure white sunlight was considered a gift from God; it was unthinkable that it could be broken down or, worse still, created by mixing colored lights together. During the Middle Ages mixing colors at all was a taboo, believed to be against the natural order; even during Newton’s lifetime, the idea that a mixture of colors could create white light was anathema.
“Artists would also have been puzzled by the idea that white is made up of lots of different colors, but for different reasons. As anyone who has ever had access to a paint set knows, the more colors you mix together, the closer you approach to black, not white….
“The explanation for the fact that mixing colored light makes white, while mixing colored paint makes black, lies in the science of optics. Essentially, there are two different types of color mixing: additive and subtractive. With additive mixing, different light wavelengths are combined to create different colors, and when added together the result is white light. This is what Newton demonstrated with his prisms. However, the opposite happens when paints are mixed. Since each pigment only reflects back to the eye a proportion of the available light, when several are mixed together more and more wavelengths are subtracted. Mix enough together and very little of the visible spectrum is reflected, so we will perceive the mixture to be black, or very close to it.”
I’m always fascinated when taking pictures of white flowers, and I had a little fun this morning poking around in my photography books and several web sites to read about the color “white” — what it is technically, how we experience it, and how representations of white in nature and in physical objects vary because of its reflective qualities and the presence of all colors in swatches of white light. Wikipedia lists nearly two dozen “shades of white” — many with clever sounding names; go to any hardware store to buy a gallon of white paint, and you’ll be greeted by many, many more. In nature, though — and certainly among flowers — white blooms are seldom pure white (if that’s even a thing), but are typically a mix of colors that change (often diminishing) as the flower opens. Yellow, green, and purple or magenta seem most common, as you can easily see if you take a close look at the white quinces below. Our eyes and minds tend to discount the color variations when we look at white flowers in nature, but the camera — it misses nothing!
“White balance” (or “color balance”) is a common photography term, of course, and can refer to a setting on the camera (or in the post-processing software) that alters the intensity of red, blue, or green applied to an image when it’s taken or developed — often interpreted as “cool” or “warm” color temperatures in a slighted mixed metaphor. I generally use the camera’s automatic white balance unless I know I have a specific reason to change it, something that I seldom do for nature photography but occasionally change when taking pictures indoors.
A challenge for photographers when taking pictures of white flowers is that it can be very easy to over-expose the white, resulting in “blown whites” or “blown highlights” for which detail can’t be recovered in post-processing. You end out with a bright blob of white, in other words, and shape but no texture in that portion of the photograph. To help eliminate that problem, I’ve gotten into the habit of using the camera’s exposure bracketing capability — to create three images at slightly different exposures from a single press of the shutter, from which I’ll pick the best one during post-processing.
This first pair of images below features a tiny blossom I noticed at the bottom of one large batch of quince shrubs, hiding among branches of the shrub and surrounded by winter debris from fallen leaves and sticks. It was so small that I had trouble getting it in focus without falling into the shrubs; but I kept the photo anyway because I liked how it seemed so determined to grow in the most inhospitable part of the plant. If you enlarge the image, you can see traces of green and bits of magenta tinging individual petals; and that it’s nearly translucent at this stage in its life.
Some of the quinces are very self-protective; it’s pretty common to see blooms like this nestled among a series of thorns. No fingers were pricked while taking these pictures, though the flowers were in full sun and The Photographer had to insert himself between the sun and the plant to get usable photos. I wasn’t able to determine why one of the flowers thought it was a good idea to bloom upside-down.
As the blooms get larger, the petals get thicker — and the appearance of white is more saturated and less translucent. These two pairs of blossoms grew farther up on the mass of shrubs, trailing a stone wall that shaded them from the midday sun. There is less magenta in the petals at this stage, though the center of each flower reflects back shades of yellow, some of which may also be pollen dust waiting for a bee to buzz by.
This pair shows my favorite photos in the series. The background was very simple without my intervention — always a plus! — and this single flower was in full bloom on a length of over-wintered wood that, in real life, was about five feet long. The light was just right for this one — it’s the purest white of the whites in this series — and the center looks like an ornately-dressed dancer, if you like to imagine flowers as other things.
Thanks for reading and taking a look!