Wednesday, August 29, 2012

Composition in Landscapes and the Photography of Marcin Sobas

SOME INSPIRATIONAL LANDSCAPE photography, from Polish photographer Marcin Sobas, can be found here.

Ruins  by Marcin Sobas (MarcinSobas) on
Ruins by Marcin Sobas

Sobas has lately gained a lot of positive attention for his remarkable landscapes of Moravia and Tuscany.

A while back, I made an effort to learn why some landscape photography has great appeal, and I attempted to identify the common characteristics of great landscape images. Now, there is no end to advice that can be found on the subject of landscapes, but I desire to discover those characteristics that are more certain and definite. Some of my observations can be found in the article Composition, Part 2 - Composition and Subject in Landscape Photography.

From my analysis of highly-regarded landscape images, I found some characteristics that nearly all of them share. These ought not be considered unbreakable rules, nor should this list be considered exhaustive, for they are not the only things that photographers consider; rather this is simply what I saw, and there could be great landscapes that are otherwise.

1. Almost by definition, a landscape ought to have a superhuman scale. Good landscapes depict scenes that dwarf the human person, and so have the characteristic of sublimity. The sublime describes “a sense of awe, grandeur, or greatness, something that is lofty to an extreme degree, so much so that it dwarfs the human person in insignificance.” See the article On the Sublime for more details. A sublime scene may or may not be a beautiful scene, but it certainly has to be big, and Sobas’ images show rather big scenes that are sublime and beautiful.

Imagine taking a photograph of a small garden; the flowers may be beautiful, but the scene will likely lack sublimity, because the garden is of human scale. This problem of scale concerned the designers of the Victorian-era Tower Grove Park in Saint Louis, Missouri, USA, and they knew that the sublime would not be possible in their park. The results are pretty, but not lofty, as I show in the article here.

2. Unusual use of lenses can make for better landscape photos. Beginning landscape photographers often desire ultra-wide angle lenses so as to “get the whole scene in.” But consider that wide angle lenses not only get in the whole scene, but at the same time they make distant objects recede in size and scale, taking away the impression of sublimity. Wide angle lenses instead emphasize the foreground, which may include objects of a more human scale, while reducing the grand vistas of the background.

Instead, Sobas often uses a telephoto lens, a Canon 70-200mm f/4 L-series lens, which gives a horizontal angle of view of 18.2 to 6.4 degrees on his Canon 40D camera. This narrow angle of view provides foreshortening — making distant objects appear closer to each other — as we see with the hills in the photograph above. The use of a telephoto exaggerates the vertical dimension at the expense of perceived depth. Would the scenes have appeared as sublime if he had stood closer, and had used a wide-angle lens?

You may, however, consider the final size of your image and how close you will view it: if you are creating a panorama that will cover the wall of a room, then small detail becomes more prominent, and so a wider angle of view may not decrease the impression of sublimity.

Also note that Sobas often uses a high camera angle. Instead of just seeing one line of ridges, we can see multiple lines of ridges and hilltops, one behind the other, which increases the grandeur of the scenes.

3. Good landscapes are almost always taken around sunrise or sunset, or at night. I’m not saying that good landscapes can’t be taken at midday, I’m just saying that they typically aren’t. The lighting angle during the extremities of the day is low, and so shadows thrown are long, and serve to model the undulating terrain. In this way, early or late landscape photography is like using Rembrandt lighting for portraiture, which models the human face with shadow. Harsh lighting, like we find at midday, will often underexpose shadows or overexpose highlights; on the contrary, with the sun at a low angle, the sky acts as a great fill-in light. The attenuated orange light from the sun provides a good contrasting color with the blue of the sky, giving us far more color during the preferred times of day.

Autumn ... by Marcin Sobas (MarcinSobas) on
Autumn ... by Marcin Sobas

According to this interview, Sobas prefers cloudless mornings for his shooting. I’ve noticed that while sunsets are often pretty, the sky at sunrise is usually dull, but this makes for a better, more uniform light for this kind of work.

4. Unusual weather can help improve a landscape photo. Dramatic stormy skies and snow on the ground can turn an ordinary landscape into something more special. Sorbas likes foggy mornings to make his photos more interesting:

Rays by Marcin Sobas (MarcinSobas) on
Rays by Marcin Sobas

He recommends getting some knowledge of weather so as to predict the best times for taking photos. The Lawrenceville Weather website includes a fog forecast map for the lower 48 United States; I refer to this map frequently to find interesting shooting conditions. Also of use is The Photographer's Ephemeris, an application that calculates the angle of the sun; this can help to predict the direction of shadows, which may lead to better compositions.

5. Good landscapes usually have a full range of tones or color. Sobas subtly post-processes his images, and the final results do have a broad range of tones. The simple use of the levels tool, and saturation or vibrance — not done too strongly — can enhance a landscape photo without making it look overprocessed. Choosing the right subject, exposure, white balance, time of day, time of year, and weather conditions all contribute to getting good color.

6. Good landscapes typically have a unity and harmony, and avoid distracting details. A certain measure of abstraction works well. Again, many of Sorbos’images are so abstract that they, at first glance, appear to be paintings, but instead they are almost undoubtedly straight camera images with some mild postprocessing.

This is perhaps the most difficult part of landscape photography: what subject, what camera position, and what lens and cropping best suit the image? A good photographer ought to be able to view a scene, taking in both the subject as well as potentially distracting elements, instead of merely doing the same back home on the computer. Especially when an image is to be displayed at a small size on a computer screen, a large measure of abstraction is needed, more so than if the final image is larger.

7. Remember that photographs are made to be viewed by human beings, and adding a bit of human interest to an image may make a photograph more interesting to your viewers. Having a human in a landscape can draw attention to it, and in the best examples, can transform an ordinary landscape photograph into a dreamscape, deepening its emotional impact. From what I've seen, Sobas does not often include humans in his photos, but we do see buildings, boats, roads, and sometimes animals. I might add that most or all of these images depict landscapes that have been heavily altered by humans, perhaps over thousands of years, but in a harmonious way, and so they have an organic look to them.

8. Good landscape photos are usually made with good equipment and good technique. Because landscapes may not be as intrinsically interesting as a human figure, it takes extra effort to attract the eye. Journalistic style images can be rough, and that does not distract from them; indeed, a rough image may have a feeling of immediacy about it. Landscapes, on the other hand, are more timeless, and seem to call for more perfection.

There are any number of rules or principles used in landscape painting and photography, and the brief list above are merely my observations of what most good landscapes definitely seem to share. I haven’t mentioned commonly-cited principles such as the use of diagonals, leading lines, the rule of thirds, balance, avoiding subjects leaving the scene, the use of S curves, having a definite center of attention, and so forth, simply because these principles, in my mind, aren’t certain, or perhaps I simply don’t understand them well enough. Human psychology is complex, but some things are more certain than others; getting the basics right is more important than the subtleties. After knowledge, experience, and inspiration, comes more perfection.

Monday, August 20, 2012

Sensor Size and the Total Quantity of Light

IT IS SOMETIMES SURPRISING that even inexpensive cameras can take good quality images in the bright mid-day sun. I've seen many photos from cell-phones and from ridiculously cheap point-and-shoot cameras that have more than adequate image quality. Maybe these images aren't particularly optically sharp, but even low-end cameras can produce images in full sunlight that have a low amount of digital noise. They are “good enough.”

But one of the overarching rules of thumb in photography is that the larger the sensor size (or film size), generally speaking, the better the image quality of the final photograph. A bigger sensor makes it easier to have a lower noise image, a bigger sensor makes it easier to make matching quality optics, a bigger sensor makes it easier (up to a point) to make an ergonomic camera, and so forth. Now, I'm not saying that quality photos can’t be taken with a tiny image sensor, rather, it is easier to take an image with higher technical image quality by using a larger sensor. See the article One Easy Rule for Quality Images for more details.

A comparison of camera sensor sizes. [Source and attribution]

As noted, even low-end digital cameras can produce good images in broad daylight. The problem is that their image quality tends to sharply decline as the light gets dimmer. These cameras, taking photos under dim incandescent lighting, produce images that are a noisy mess, with terrible color rendition and digital grain ruining the sharpness of the image. Now, perhaps a tripod could help, but certainly these kinds of cameras are very disappointing for hand-held images.

Our eyesight doesn’t work as we might naïvely think. One scene, which to our eyes appears to be slightly dimmer than another, might in fact have half of the total amount of light falling on it. Likewise, a scene that appears to be only somewhat brighter than another might in reality be twice as bright.  In particular, where I live, in the mid-lattitudes of the northern hemisphere, we get to enjoy long periods of dusk in mid-summer; the fading daylight seems to last for hours, until we finally notice that it is very dark out. Our eyes valiantly attempt to see in the dimming light, until the laws of physics and biology finally conspire against our vision, and we are plunged into darkness. Our eyes attempt to flatten out the huge range of brightness that we experience.

A hazy day may be objectively half as bright as a sunny day, although it certainly seems to be only slightly dimmer. A cloudy day may be one fourth as bright, while an overcast day may be one eighth as bright. At sunset, it may be one sixteenth as bright as a bright sunny day, and a bright day may be thirty two times as bright as what we find at dusk. On ground covered with snow or white sand, a scene may be twice as bright as what we are accustomed to, and there is a real risk of contracting snow blindness due to the excessive amount of light.

Cameras, like eyes, are designed to work over a large range of brightness. Camera lenses have adjustable apertures to vary the amount of light hitting the sensor, and the shutter speed can be varied over a large ranges of values. The sensors also have varying amounts of sensitivity to light. But a sensor with twice the surface area of another collects twice the total amount of light, and we could assume (all things otherwise being equal) that it can operate similarly in light that is half as bright.

Now I've taken decent photos in dark places with a cheap point-and-shoot camera, but that was only when the camera was sitting on a tripod and its shutter was open for a long time. I certainly could not hand-hold the camera and expect to get anything else except digital noise. However, I can and do often take fairly decent hand-held shots at dusk with my Nikon DSLR. The major difference between these two cameras is simply the size of the sensor: the Nikon lets in a far larger total amount of light.

Same scene taken with a newer cell phone camera on top, and an older DSLR camera on the bottom.

We know that cheap point-and-shoot cameras, selling for less than US$50, and having tiny sensors, can take good images in broad daylight with little digital noise. Let us take this quality as our baseline, and determine what size of a sensor we need if we want to take images of similar quality and with similar camera settings under dimmer lighting. This table shows standard digital sensor sizes, along with the lighting conditions that would be equivalent to typical cell phone cameras in bright daylight:

Sensor size Use Sensor area in square millimeters Lighting condition
1/4” Cell phones and toy digital cameras. 7.68 Bright daylight
1/3.2” Premium cell phone cameras. 15.5 Hazy sunlight
1/2.3” Compact digital cameras. 28 Cloudy bright
1/1.7” Premium compact cameras. 43 Light overcast
2/3” Some bridge cameras. 58 Heavy overcast
CX or 1” Nikon 1 series. 116 Sunset
Micro 4/3rds Olympus and Panasonic mirrorless interchangeable lens cameras. 225 Dusk
APS-C Most Nikon, Pentax, and Sony DSLRs; lower-end Canon sensors are slightly smaller at 329 square mm. Also found in some premium rangefinder cameras. 370 Indoor sports, stage shows
35mm, “Full frame” High-end cameras from Nikon, Pentax, Sony, Canon, and Leica. 864 Bright street lighting at night

A camera sensor that has twice the surface area ought to produce an image with a similar amount of digital noise when the lighting is half as bright, all things else being equal. Certainly there are more factors involved, but sensor size is one of the most significant when it comes to image noise.

Photojournalists tend to use the cameras near the bottom of the list, especially if they need to capture a scene in dim lighting without the use of a flash. Note that the Micro 4/3rds cameras are fairly close in sensor size to the APS-C sized cameras, and their discrete size and noiseless operation make them viable for some work under dim lighting. Manufacturers have recently been putting the larger APS-C and 35mm sensors into compact cameras, which many photographers find highly desirable.

For more information, along with some of the data I used to make the table above, see these Wikipedia articles: