I am often totally fascinated with “light”. As a kid I used to stare at light. All kinds of light. Reflected light, refracted light, morning light, daylight, evening light, twilight, moonlight…. and on and on. We were taught to position the sun behind us in photography but often my images are directly into light while using shadows to hide in. Then there’s a colour. As a young photographer I couldn’t afford colour so I shot everything in B&W. In hindsight I have better images and captured my imagination so much more than I realised. Colour sometimes robs me of whats happening tonally and visually. If you look at a B&W picture often there are just so many grades from pure white to full black. Whereas in a colour picture you cannot see that; well you do see it but its all different colours. This is just my spin on this whole thing. I read this morning an excerpt from Ansel Adams website. It’s worth reading so I have copied a bit here in my blog.
Taken from Ansell Adams website: Photographers speak fondly of the golden hour of light just after sunrise and just prior to sunset, a brief window of time that features lower contrast, warmer hues and pronounced shadows that typically add drama to the scene, and are easier to capture on transparency film or digitally. Hence, conventional wisdom dictates that the most compelling color landscape images are typically made within the first two and last two hours of the day.
In the summer months when there can be nearly 16 hours of daylight in Yosemite , the time between the first and last two hours of the day can seem like an eternity. Not so November through March, when one hardly has an opportunity to put the camera away. And that’s just midday.
Have you ever stared in disbelief at the color of light in an image of a Yosemite sunset? Have you noticed how many of those images depict autumn, winter and early spring scenes?
Here’s the secret: The color of the light in Yosemite gets warmer in the cooler months.
Why? A number of factors are at work.
The biggest contributors are the 23 degree tilt of the earth’s rotational axis and something called Rayleigh scattering.
The axis tilt affects the angle at which the sun’s rays strike the earth and how much atmospheric haze they pass through before they reach the object they are illuminating. At high noon in June in Yosemite, the sun is approximately 70 degrees above the horizon, which is noticeably high in the sky. It appears bright and white, in essence unfiltered, with all its visible wavelengths of light reaching their destination with equal intensity.
High noon in November, however, the elevation of the sun is only half that, hovering around 35 degrees above the horizon in Yosemite . Lower in the sky like this, its rays are passing through much more atmospheric haze on their earthward journey, and that is when Rayleigh scattering kicks in. Named for John William Strutt, 3 rd Baron Rayleigh, an English physicist and winner of the Nobel Prize for Physics in 1904, the principle explains how shorter wavelengths of light are scattered by minute air molecules and particulate. In brief, the shorter blue, green and sometimes yellow wavelengths are scattered most efficiently, leaving the longer, yellow, orange and red wavelengths to illuminate the subject. The result is fiery sunsets.
Additionally, local events such as passing storms that clear the air, fog, fires and industrial pollution contribute to the equation and the intensity of the color can vary considerably.
In Yosemite, sunsets are particularly colorful because the light has to pass through the haze of the San Joaquin Valley .
The most colorful sunsets occur when there is fog in the Central Valley and a layer of clouds above. As the sun sets, it eventually gets below the layer of clouds, and for a brief period just before it dips below the horizon of the Coast Range to the west, it shines through the atmospheric haze between the clouds above and the fog below. Rayleigh scattering does its thing on the blue lightwaves, and the longer, warmer wavelengths are projected onto Yosemite’s pale granite cliffs. What really sends the color off the chart is that the light is intensified as it reflects off the clouds above and the fog below, both focusing the brilliant colored light on the park’s icons.
But, we started off talking about working all day November through March. How is this possible?
The wonderful quality of light that exists during golden hour is present nearly all day long owing to the fact that the sun never gets very high in the sky. From most vantage points along Northside Drive in Yosemite Valley, the sun creeps along the top edge of the cliffs on the south side. The southern forest is in shade most of the day and the high noon solar elevation of 35 degrees in early November is equivalent to where the sun would be at 8:45 am in June. It is like morning, only all day long. Get your cameras!