Kirk Marshall Photography Kirk Marshall Photography

Blog

Zoom, Zoom

November 12th, 2019

When standing in front of a scene you’d like to capture photographically an early decision that needs to be made is how to frame the image. 

If you’re using a fixed lens (single focal length) you have to move your physical position relative to the subject in order to adjust the framing of the composition. This is kind of a human-zoom; you walk forward to zoom in or backward to zoom out. 

When using a camera that has a zoom lens you have the capability to adjust the framing of the scene without physically moving yourself. This series of images illustrates the effect of zooming in on a subject. 

image

(Published by Nikon in Understanding Focal Lengthhttps://www.nikonusa.com/en/learn-and-explore/a/tips-and-techniques/understanding-focal-length.html)

Optical vs Digital

Digital cameras use a image sensor to capture the viewed image. Light from the subject passes through the lens and falls upon the sensor which interprets the light and captures the image. The sensor is comprised of thousands of pixels, each capable capturing a single point of light and color to be used in the rendered image. The size and density of the pixels on the sensor have a direct effect on the quality of the resultant image.

Many lower-end cameras offer two types of zooming: optical and/or digital. Optical zooming alters the resultant image using the physical capabilities of the lens to optically alter the view area to be captured. If the camera is capable of taking a 12 megapixel (MP) image, all images captured using the optical zoom will be 12 MP in size. 

Digital zoom is different. If you use digital zooming the result is a smaller number of captured pixels and therefore a smaller image, perhaps only 10 or 8 MP. The camera accomplishes digital zoom by excluding pixels on the edge of the sensor and only capturing information from the pixels in the center.  The end result of using digital zoom is as if you took a full sensor image and cropped the result later using image processing software (e.g. Lightroom). 

Some cameras include software that will automatically expand a digitally zoomed image to match the pixel count of a full-size image (in the case discussed here: 12MP). The full-sized image is built off the reduced set of pixels from the center of the sensor and can only provide the resolution/detail available in those pixels. Again, the same results can be achieved post-capture using a full-sized image and image processing software.

Portrait Perspective

November 5th, 2019

When taking a portrait, or headshot, our natural inclination is to fill the frame with the individual’s face, neck and shoulders. If the lens we’re using has a short focal length (a wide angle lens) we’re going to have to get close to the subject in order to fill the frame. If we take the portrait with a normal lens we’ll need to be a bit farther away and with a telephoto lens, even farther. So how does that effect the image?

In my last post I shared the album cover from Don McLean’s American Pie. In that image Mr. McLean’s thumb is as big as his head. The effect is the result of using a short focal length which accentuates, or enlarges, items close to the camera and diminishes, or shrinks, object farther away. 

How will that effect a portrait? Since the individual’s nose is closer to the lens, it’s going to appear enlarged with respect to the rest of the face. In a portrait taken with a slight wide angle lens, say 24mm (on a 35mm base), the effect might not be readily apparent, however as the focal length shrinks it becomes more and more so. Most people find portraits taken with a wide angle lens unflattering. 

By contrast portraits shot with a normal or slight telephoto lens provide a more flattering rendering of the subjects face and are generally preferred. In fact lenses in the normal (50mm) to slight telephoto (85mm) range are frequently referred to as portrait lenses. 

image

(Canon 5DMII, EF100mm, 1/60s, f8, ISO 200)  

Normal, Perspective

October 29th, 2019

In my post last week I mentioned that in between wide angle lenses and telephoto lenses are normal lenses. What is a normal lens? 

Mathematically, a normal lens is one where the focal length is approximately equal to the diagonal of the sensor. 

Traditionally, 35mm cameras are the common, base standard against which many things are referenced, so let’s start there. 35mm film was 35mm wide and 24mm tall; doing the math we find that it has a diagonal of 42.4mm. So a normal lens on a 35mm camera would be somewhere around 42mm. In practice a normal lens can range from 40 to 50mm (and sometimes a bit beyond that). 

Practically, a normal lenses is one that renders the scene in a perspective that mimics our normal perception of the world. To better understand a normal perspective let’s consider an abnormal one; like the cover from Don McLean’s album American Pie.

image

How many people do you know who’s thumb is as big as their head?  

In this image the artist used an abnormal perspective to emphasize the American Flag painted on Mr. McLean’s thumb. The distortion of the relative sizes of the thumb, fist and head was accomplished using a wide angle lens that renders things close to the lens as large and things farther away as small.

Again, a normal lens is one that renders the relative size of objects in a manner that mimics our natural vision.

As you might expect from the previous discussion, a telephoto lens does the opposite of a wide angle lens and renders objects in an image visually compressed, making the resultant scene appear somewhat flat. This image of the Utah State Capitol building and State Street was shot with a 200mm telephoto lens. 

image

(Sony a7RII, Canon EF70-300 @ 200mm (w/ Metabones converter), 3.2s, f/14, ISO 400)

Since the definition of a normal lens is dependent on the size of the sensor it follows that what is a normal lens for one sensor wouldn’t be normal for a different sized sensor. For example, the sensor in my cell phone is approximately 8.5mm and therefore a normal lens as discussed above wouldn’t be normal on my cell phone. 

The choice of lens can have a tremendous impact on the final image, rendering the scene in a normal perspective or distorting it in one way or another. Choosing the appropriate lens to help you convey your vision is a choice that should not be ignored and must be made early in the photographic process. 

Lenses

October 22nd, 2019

The last subtopic I’m going to discuss with respect to composition is lenses.

The choice of lens can have a significant effect on the resultant image and it’s choice should not be ignored. 

With respect to lenses, there are three basic types of cameras: fixed-fixed lens, fixed-zoom lens and interchangeable lens.

Fixed-fixed lens cameras have a permanently attached (the first fixed) single focal length (the second fixed) lens. (A fixed focal length lens can also be referred to as a prime lens.) Probably the most common example of this type of camera is the one in most cell phones; neither the lens itself nor the lens’ focal length can be changed.

In a fixed-zoom lens camera, the lens is permanently attached (fixed) but the focal length is adjustable (zoom). Most entry level cameras are of this type.

Lastly, most mid- to high-end cameras allow for interchangeable lenses. In these cameras the lens is a separate unit that attaches to the camera body using a mounting ring that locks the lens to the camera and provides connectivity for mechanical and electrical control of the lens. Typically there is a wide range of lenses that can be purchased and used with the camera body; some of which are fixed focal length and some which are zoom lenses.

Focal Length

Focal length is a term which refers to how strongly a lens converges rays of light. A short focal length converges rays in a shorter distance and a longer focal length converges rays over a longer distance. That definition bleeds over into our vernacular since we refer to a lens with a long focal length as a long lens, it usually has a long physical length as well. 

If you’ve ever used a handheld magnifying glass you’ve had direct experience with focal length. To see something clearly through the magnifying glass you probably had to adjust both the distance between the glass and the subject and the glass and your eye. What you were doing is finding the focal length of the magnifying glass.

Focal lengths are expressed in millimeters (mm) and range from very short (16mm) up through very long (600mm). (For reference, one inch is 25.4mm.) Short focal lengths are referred to as wide angle lenses and long focal lengths are called telephoto lenses. In between these two extremes, in the middle of the range are normal lenses.  

image

(Mituraju Sunrise, Canon 5DMII, EF24-105 @ 28mm, 1/60s, f8.0, ISO400)

Flow to Contrast

October 15th, 2019

Years ago I had a Rhodesian Ridgeback that I took with me on a backpacking trip. He had his own backpack (saddlebags really) with food and a bed roll to keep him warm at night. Everything was going great until we stepped out into a meadow and spotted a pair of moose a couple of hundred yards off grazing in the wetlands down by a stream. He took off bounding across the grass with the saddlebags flapping like wings. 

It was close to an hour before I saw him again… and when I did, he was missing his backpack. 

There wasn’t much I could do about the lost pack so we headed on down the trail toward our destination and what was going to be a cold, hungry night for him. Soon something caught my eye, a pop of red and yellow color in a forest of green, 80 yards off the trail. I had to back up a bit, do a second take, and then bushwhack through the brush but sure enough it was his pack; skewered on a broken branch of a downed tree that he’d ducked under. 

Our vision has been tuned over millennia to help ensure our survival. When viewing an image we’re visually drawn to human forms, regions of sharpness, areas of high tonal contrast and pops of color.  

Consider this image of St. George’s Tron in Glasgow, Scotland. 

image

(Canon 5DMII, EF24-105 @ 105mm, 1/180s, f5.6, ISO 100)

As a photographer my job is to direct your gaze at what I want you to see; in this image it’s the church. I am able to accomplish some visual direction through the lines in the photograph that I used when lining up the shot. These lines (the sidewalks and building tops) create visual flow that directs and draws your gaze toward the center of the image where you visually settle on the church. 

The problem with this rendering is that there are other elements pulling your attention out and away from St. George’s Tron. The bright red pops of color in the bottom half of the image distract and draw our attention down away from the building. The blue areas on the left (scaffolding) and right (trailer/dumpster) act similarly, as does the yellow sign in the lower left.

When composing this image there was little I could do about those distractions so I shot the image as you see it here (well, I cropped and straightened it) and then addressed these other distractions in post-processing. 

Here’s the final image.

image

So what did I do? 

Well, obviously I converted it to monochrome. The real subject of the image is the buildings, particularly the church. In the first rendering you’ll notice that the buildings are almost completely monochrome already. The things that are not are the ones that distract from the scene. By converting it to monochrome I’ve eliminated all the pops of color that were drawing the viewer’s attention from the central theme. 

Additionally, I’ve added both a tonal and focal vignette; darkening and blurring the edges of the image. Visually we are drawn to areas of highest tonal contrast (differences between light and dark). The tonal vignette therefore ensures that the highest tonal contrast areas are located on the front of the church. Visually we avoid focusing on areas that are blurry. The focal vignette blurs the edges of the image encouraging our gaze to return to the center should we venture away from the church. 

These two contrast changes assist the lines of flow to create a much stronger image. One that directs and hold our attention on St. George’s Tron and conveys my vision and impression of the scene when I was standing there in the street. 

The first image might be described as an image of a street scene. The second rendering is clearly a picture of a church, which was my intention with the image. 

Contrast

October 8th, 2019

Before we talk about contrast as it relates to flow, let’s address contrast in a general sense. 

Contrast is the holy grail of photography. It’s what makes an image an image. Without contrast we’d be looking at a solid, square of uniformly colored space. And while that maybe considered art in a broad definition of the term, it’s probably not why we picked up a camera and starting shooting.  

There are four basic types of contrast: tonal, focal, textural and color. It is through careful use of one or more of these types of contrast that we share our view and feelings about the subjects we shoot.  

Tonal contrast refers to the light and dark values that are used to create an image. 

image

(Canon Rebel XSi, EF-S15-85 @ 35mm, 1/125s, f22, ISO 100)

In this picture, of snow banks along a small creek, the image is constructed almost entirely of strong tonal contrast. The dark water of the creek juxtaposed against the white snow banks is the major theme of the image. 

image

(Canon Rebel XSi, EF50, 1/90s, f2.5, ISO 1600)

Focal contrast refers to the use of sharpness and blur within an image. 

In this image, taken at Old Mission San Jose, CA, the main subject is a figure of Christ and the surroundings have been blurred and fractured to give some limited context to the scene while not detracting from the central subject. 

(In the upper-right of the picture you can see what looks like a dinner plate or shallow bowl on the wall. The object is covered with small glass mirrors and has a candle holder in front of it. It was used to illuminate the hall before the advent of electric lights. I pointed my lens at one of these reflector dishes at close range to shoot this image.)

image

(Fujifilm X100T, 23mm, 1/40s, f8, ISO 500)

Textural contrast refers to the use of textures to create an image. In this picture of a forest scene, the main story is the variety of textures in the fore, middle and backgrounds. 

Lastly, an image can be constructed using color contrast. 

image

(Sony α7RII, FE 24-70 @ 70mm, 1/200s, f11, ISO 100)

The interest in this image of a field of tulips is largely due to the color contrast between the green plants and red flowers. The small black and white inset shows the same image desaturated and the visual interest is mostly gone. 

No image is purely one type of contrast. The tonal contrast image (first image) has some textural characteristics and both the focal and textural examples clearly have some tonal contrast too. All images employ a mixture of contrast types and each of the types contribute to the overall interest of the image. 

Elements of Flow

October 1st, 2019

There are at least two elements that influence a viewer’s scan of an image: lines and contrast. Lines are elements of movement, guiding or directing the flow through the image; points of contrast are the elements that provide resting points. 

Consider this image of the steps leading down from the Wat Khao Chong Kaeo temple in Prachuap Khiri Khan, Thailand. 

image

(Canon 5DMII, EF24-105 @ 75mm, 1/50s, f8.0, ISO 100)

The bright white banisters along the stairs lead the viewer’s gaze from the lower part of the image through the center and up to the small building at the top of the image. At the building the banisters stop and consequently so does our flow. In this image there are real, solid lines that direct our gaze through the image. 

Now consider this image of a waterfall in the Cordillera Huayhuash of Peru.

image

(Canon 5DMII, EF24-105 @ 28mm, 1/6s, f11, ISO 100)

In this image we find our gaze resting on the small rock in the middle of the waterfall just up and left of the center of the image. There are no strong, hard lines like in the previous example but there are implied lines that are influencing our experience of the image. As our eyes wander about, exploring the textures and contrasts, these implied lines keep bringing our attention back to that central rock. 

Some of these lines are strong, short and straight, like the thin and very straight line of water in the upper right, and others are very vague and fractured like the long division between the water and rock that curves from the lower right corner up and left to the center of the image. Many of them work to keep our focus within the image and draw our view into the center. 

Here’s one more image, of my grandson at a lake in Missouri. 

image

(Canon Rebel XSi, EF50, 1/750s, f6.7, ISO 200)

In this image the flow directs our gaze from his face to some point on the shoreline. In this image there are no lines, real or implied. There’s just his intent focus on whatever it is that has caught his interest, but even as an imaginary line it’s enough to add some flow to the image and cause us to scan for whatever it is he’s looking at. 

Next time you’re looking through your lens think about the image you’re trying to capture and try to add energy, movement and dynamics into the two dimensional scene with lines, real or implied, that guide the viewers gaze through the image.

Flow

September 24th, 2019

We don’t just look at a photography, we scan it. Our eyes move through an image following real or imagined lines searching for places to rest. That pattern of eye movement is called flow and it is the responsibility of the photographer to direct and lead the viewer’s gaze through the image.

Flow helps create the perception of three dimensional space within the two dimensional image and imbues energy, movement and dynamics into a flat, static print. 

Consider this image of daffodils on the hills at Ebey’s Landing, WA. 

image

(Sony α7RII, FE 24-70 @ 36mm, 1/250, f9.0, ISO 400)

When I look at this image I initially focus on the bright flowers; but then I’m drawn into the image following the shoreline into the upper right where it fades to grey and merges with the clouds. My scan of the image takes just a fraction of a second and if I’m not paying attention I’d miss the movement completely. Even though the movement is brief, it has the desired effect on the viewer and creates an energy that helps make the image more interesting. 

The image above has a rather simple theme and subject matter and hence the flow is also rather simple. Other images with multiple subjects or focal points might have a much more complex pattern of flow.

Spend some time looking at several images; they can be your own or someone else’s, maybe on Facebook or Instagram. As you look at them notice how your gaze moves through and scans over the image. What draws your eye through the frame? Where does your focus come to rest? 

The next time you pick up a camera think about the scene you’re trying to capture, try and work toward a composition that has flow that captures the viewer’s interest. 

Tension Modes

September 10th, 2019

We can introduce tension into our images using a number of mechanisms or modes. 

In my last post I talked about creating tension through the placement of our subject or focal point. The closer the subject or focal point is to the center of the image the less tension will be present in the image. Moving the subject or focal point away from the center creates increasing levels of tension.  

Part of the tension that’s introduced when we decenter the subject is due to the imbalance that’s created. Consider this image from the Reichstag Building in Berlin, Germany. 

image

(Canon 5DMII, EF24-70 @ 60mm, 1/200s, f11, ISO 1250)

The people in the image have been placed on the right side of the image which induces tension through their placement (placement tension); like the marble hovering up the side of the bowl (see blog post from Sep 3). Additional tension is also present due to the comparatively dark tonal values on the right side of the image (tonal tension). These dark values are visually heavier and induce feelings in the viewer that the weight should drag down that side of the frame. 

While the horizontal placement of elements seems to have the greatest effect on balance and tension, vertical placement has an effect as well, though it may be more subtle. In this image of the Carillon in Berlin, Germany there are several modes of tension acting on the viewer. 

image

(Carillon, Canon 5DMII, EF24-105 @ 105mm, 1/160s, f11, ISO 100)

The most noticeable tension is the placement of the Carillon itself, left of center. But there are also elements of tension through the vertical location of elements, or rather the division between elements. The division between the trees and the sky is about a third up from the bottom and the top of the Carillon placed about a third down from the top. The placement of these divisions adds tension that wouldn’t be there if they were placed centrally. There is also a strong tonal and textural imbalance between the light, smooth sky and the darker, leafy trees. 

As a photographer understanding tension and being able to architect the right amount of tension to convey your vision is key to composing an image you’ll be proud of. 

Tension

September 2nd, 2019

Another basic concept in image composition is tension. What is tension and how does it relate to photography? 

When the Microsoft Windows XP development team contacted Charles O'Rear about his image Bliss (see my blog post from Aug 6) he reportedly thought "Were they looking for an image that was peaceful? Were they looking for an image that had no tension?“ (https://en.wikipedia.org/wiki/Bliss_(image)).

To understand tension, imagine a bowl and a marble. If you take the marble and release it near the upper lip of the bowl it’s going to roll down the side and eventually settle and stop right in the middle of the bowl. The center of the bowl is a static place of rest and peace for the marble. If sometime later you walked by the bowl and caught it out of the corner of your eye, you’d see the marble at rest in the bottom, center of the bowl and think ‘all is as it should be’. But, if you walked by and saw the marble NOT in the center but saw it half-way up toward the rim, you’d do a double-take. You’d have to stop and look closely and ask ‘WTF, how is it doing that?’ That’s tension; something that is not at rest or out of balance. Tension is the something that captures and holds a viewers attention.

Consider these two images.  

image

(Canon 5DMII, EF24-105 @ 24mm, 1/180s, f13, ISO 100)

In this first image Pippa is the focal point and I’ve positioned her dead-center, like the marble in the bottom of the bowl. Creating a restful feeling and an image with very little tension. 

image

(Canon 5DMII, EF24-105 @ 58mm, 1/400s, f5.6, ISO 800)

Now consider this image of a Thai vendor trying to sell her wares to tourists. The vendor with her wares dominates the center of the image and the tourists are cornered by her along the left edge. The image is very out of balance and–I hope–conveys the tension and pressure a tourist feels at the onslaught of the horde of vendors at any tourist attraction.  

Many of the compositional ‘rules’ of photography are designed to help you as the photographer capture tension in your imagery. The rule of thirds suggests putting your subject or focal point about one third of the distance in from one edge. Supposedly this creates an ‘optimal’ about of tension; not too much, not too little

Should all photographs have tension? Clearly the answer is ‘no’. Bliss is virtually tensionless and yet sold for a large, but undisclosed, sum. If you’ve been commissioned to provide photographs for a dentist office, it’s probably best to minimize tension, the patient experiences enough just sitting in the chair. 

On the other hand, if you’re photographing environmental abuses you probably want to maximize tension to unsettle your viewers and motivate them to action. 

How much tension is enough? I think right amount is whatever it takes to convey the photographer’s vision and mood.