The color of magic

The photo that I couldn't capture in the previous post

Okay, that was a shameless Terry Pratchett reference, but c’mon, I’m working alone, here. Editors are supposed to come up with the headlines…

A very key element of nature photography is doing a lot of shooting in the early morning and early evening, dawn and dusk. These are often called the “golden hours” and extend from roughly 45 minutes before sunrise (first light) to an hour afterward, and an hour before sunset to 45 minutes afterward. There are several reasons why this time is so good, other than the obvious sky colors from sunrise and sunset. In the morning, the air is usually still, the dew is present, and the night animals are occasionally still visible while the day animals are just getting active – if you like songbirds, this is your time. Another factor is the fact that both film and digital cannot capture the range of light levels that our eyes see, and thus images are increased in contrast from the actual view we’re looking at. During the bright midday hours, the contrast is very high to begin with, so it’s very easy for photos to become so contrasty that highlights, such as white snow or people’s foreheads and cheeks, can be “blown out,” overexposed to pure white without any detail, while shadows go in the opposite direction and lose definition in the darkness. You can adjust exposure to compensate for one or the other, but then make the opposite side much worse.

Dawn and dusk, however, have more light scattered from the atmosphere while the direct sunlight is filtered through a greater amount of air, reducing contrast greatly and softening shadows. Even more useful, however, is the color of the light. This is something that I spend time pointing out to new photographers, because it makes a significant difference to photos, but many people don’t consciously realize it. Light has character, properties that say something about the conditions and environment of the photo’s subject. That “golden hour” gets its name from a small play on words – not only does it produce photos worth more than other times, but it actually produces gold (or amber, bronze, or orange) colored photos. The very same colors we see in the sun and the sky color the subjects as well. Photographers refer to these as “warm” colors, and the opposite end of the spectrum, when light goes towards blue, as “cool” or “cold” colors. The latter is understandable – when the sun goes behind clouds, it cuts out much of the red spectrum and the light goes blue-grey, and the air temperature gets colder.

The thing is, we recognize this subconsciously, even if we never seem to notice it in the photo. Most viewers would have no problem considering these two images as taken at sunrise, but if you asked them how they knew, they might not provide a good reason. Our brains often translate the colors into what we expect them to be, so the snow is “white,” and not, in both of these cases, actually a pale yellow-orange. Even more interesting is the fact that the snow in the shaded portion of the above image comes much closer to matching the hue of the sky than the snow in the sunlit portions of the image. When you do photo editing, you start to be come more aware of the actual colors versus than the perceived, something that I imagine good painters utilize as well.

These colors tell us a lot. The warm yellows, oranges, and reds are more inviting to us in nature scenes, at the least telling us the skies are clear even when the sky isn’t visible. Two examples can be found here and here, and my Coastal Gallery gives examples of using the golden hours to make the sky more interesting.

Now, a quick side note. The phrase “color temperature” refers to the color-shift that very hot things go through as they get hotter, and is actually inverted from the way I’ve used it here. You know that molten metal, rock, and glass all glow, right? That color actually indicates a specific temperature, and it’s the same for each – molten metal that’s the exact same shade as molten glass also holds the exact same temperature, and this even applies to the surface of stars. Red and orange things are actually cool, in relation to what they could be, and red dwarf stars are among the coolest to emit light. When things get hotter, they go towards the blue end of the spectrum. We refer to color temperature of light sources in a unit of measurement called “kelvin” (k) and the higher the kelvin, the bluer the light. So photographers also know that 4000k lights are “warm” yellow, while 6500k lights are “cool” blue. Strange but true, and it all comes from our associations with things like warm fires, partially because virtually nothing we burn actually gets blue-white. If it did, we’d tend to be much further from the fires…

Getting back to using light for photography, there’s a couple of other subtle things that come from the golden hours. The first, also visible in most of these examples, is the light coming from a lower angle, sidelighting the subject rather than coming from above, and this can also serve to highlight textures and give a bit more depth and shape to the subject. Studio photographers use this all the time with extra lights to define their subjects’ shapes better, while direct, on-camera flash units do a bad job and flatten the shapes – this is what produces the old saying, “the camera adds ten pounds.” It’s not the camera, it the lack of defining shadows to enhance shape.

The second, very subtle factor, is that the yellow/orange tones contrast nicely with blue skies, making both colors more distinct. In this image, shot towards the sun, the sky has bleached out to white, a standard effect of that viewing angle. The yellows of the snowy branches become very subdued, and you notice the blue of the shadowy snow lower in the photo a lot more. But the photo in the middle of this post was taken only minutes earlier, but facing 180º away. The sky becomes the deepest blue in that direction, and the colors the richest. The sky contrasts nicely with the yellow cast on the snow and it becomes much more vibrant, even though the contrast range (the difference between highlights and shadows) is greater in this image.

So, if you want more compelling nature images, get out early. And be aware that light changes very rapidly in these conditions – the sky colors, most especially, will transition in minutes or even seconds, and the rising or setting sun will track sun patches and shadows across your subject quickly. If the sun isn’t illuminating your subject the way you want, be patient – it might change in the next few minutes (the sun and moon move their own width across the sky in a mere 150 seconds, two and a half minutes – another useful tidbit.) It may be hard getting up early enough, it may be cold, but the impact on your photos is well worth it.

Stay tuned, and I may be back with a blog post (or page link) for making your own chart for rise and set times for both sun and moon. It’s a handy thing to have, especially when you’re at nice scenic locales. It’s also good to have a compass and know how to use it, so you can plot the direction the light will be coming from, or where the moon will appear above the horizon. Good planning leads to great photos.

2 comments to The color of magic

  • Mal

    I found this whole blog entry very interesting, especially the stuff about how we perceive colour. But it has also left me with some confusion. If I take a picture under artificial lighting and then correct it by adjusting white balance am I adjusting the picture away from how it actually was towards my perception of how it was?

    Also, I don’t know how you achieved the picture of the sun through the trees. I’m sure if I did that the trees would be in silhouette without detail. Is some special technique involved?

  • Al Denelsbeck

    If I take a picture under artificial lighting and then correct it by adjusting white balance am I adjusting the picture away from how it actually was towards my perception of how it was?

    For the most part, yes. We seem to have a built-in compensation for color shift – we know something is white, so we see it as “white” even when the light colors it differently. With a little effort, you can see the true color, but it’s often easier to see in a photo editing program by sliding in a patch of true white to compare.

    There’s another aspect, though. Both film and digital sensors have a fixed color response, either the color filter over the digital “pixels” or the colored gel that the film emulsion is emdedded within – neither sees “true” color. I touched on this briefly here (a little above the stump photo.) If you notice, models in magazine photos around 2003 or so began taking on a ruddier, brownish hue because digital sensors are not the best for skin tones, compared to the specialized portrait films previously used. There’s only so much you can change a color register before it begins looking weird, and if you never captured the range of colors in the first place, the only thing you can do is “paint” them back in.

    Fluorescent light is among the worst to shoot in, since it doesn’t have a full spectrum, but large blank patches, as well as a color shift. It plays havoc with many films, and while digital is better, the white-balance compensation can leave skin tones looking very rough. Sodium streetlights can do the same for my preferred films, turning from the warm orange glow to a sickly green on Fuji Provia 100F (slide film.) The difference is astonishing (and annoying.)

    White Balance is handy to have under artificial light, which almost always has a color cast, but should be shut off for natural light if you want the warm colors to show through, or if you want the mood from colored lights.

    Also, I don’t know how you achieved the picture of the sun through the trees. I’m sure if I did that the trees would be in silhouette without detail. Is some special technique involved?

    You know, this probably needs a complete post someday, but I’ll give you a quick (heh!) answer anyway. It’s simply exposure compensation, which most cameras allow you to do, whether by locking exposure on a darker area then re-aiming into the light, or adjusting a dial to overexpose the image, in this case one and one-third stop (as I look to the EXIF info, very handy!)

    The exposure meter in a camera doesn’t know what it’s aiming at, so it’s made to provide camera settings for an “average” scene, basically middle tones (sometimes called “18% grey”.) In this case, it would indeed have rendered the trees in silhouette and the sky much darker. So when aiming at a subject that’s very bright – into the sky, snow, beach, white backgrounds, white dresses – you have to compensate for the camera trying to render this into medium tones. Since the camera will make these darker, you adjust to overexpose. The simple rule: if bright, make brighter; if dark, make darker. The other trick, mentioned first, is to aim the camera at something that is in average light, often just down a bit away from the sky, and lock exposure on that – on many cameras, it’s the * button. Digital lets you practice this, and EXIF info can help you know what works best, since the preview LCD isn’t always the best indicator.

    It’s not an easy thing to grasp, and possibly the topic I spend the most amount of time on with my students, so it deserves more depth. Thanks for the idea, and check back within the next week or so ;-)