Photographers and cinematographers often use film or digital cameras that incorporate interchangeable lens systems, meaning that different types and sizes of lenses can be attached to the camera. The purpose of using different kinds of lenses is to provide the photographer or cinematographer with a variety of options when choosing how to form an image of the scene being recorded. While there is a vast selection of camera lenses to choose from, the most common variables involve how large or small the lens causes the subject matter to appear on the recording medium, relative to its actual size as seen by the human eye.

While there are a number of technical criteria that describe a camera lens, the one often considered first is the lens’ focal length. Strictly speaking, the focal length of a lens is the distance, usually described in millimeters (mm), from the center of the lens to a parallel plane where the lens converges the light rays to form an image. This focal plane is where the recording medium - film or electronic sensor - resides. See the simple diagram below...

August 2010 Newsletter

Project of the Month

The South of America

Tech Tip

The basics of lens focal length

All original imagery and written content copyright © 2010 by Digital Media Services & Consulting LLC. All rights reserved.

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Marketing Tip

The art of saying “Yes”

Back in July of 2009, we touched on a couple of  circumstances that might warrant you saying “No” to your clients. This month, we remind you of the power of a “Yes” response.

Clients prefer to do business with service providers and vendors who are easy to work with. Those with positive, can-do attitudes tend to have more success. Does this mean that we all need to become “yes men” in order to get work?  No, not at all. But it does mean that we need to be cognizant of our initial reactions to client requests.

Surely we all have clients (or even bosses) who are constantly coming up with harebrained ideas. We also have experienced times when several different clients have come to us with the same, hot marketing concept that we already know is a waste of time and money. We become so used to these individuals spouting about their latest scheme or have heard that same, tired idea so many times that we tend to immediately offer up our “No, that won’t work” response. But, even though we may be right, if we’re not careful, we might become known as the negative, hard-to-work-with person.

A better approach to quelling these less-than-stellar suggestions might be to focus on the intended result rather than the means to get there. After all, the idea is usually driven by a desire to accomplish something rather than to simply see a particular concept come to fruition. Respond positively to the idea-generator’s enthusiasm to try something new or make a change to the status quo and begin a discussion to discover what the intended outcome is. Then, if the idea to accomplish that outcome is still not viewed as the best approach, at least your discussion can then turn to better ways to achieve your client’s (or boss’) goals rather than simply one that shoots down the idea entirely.

If the client (or boss) still insists that his or her idea is the way to go, then don’t fight it. You’ve done your job as a creative professional in providing your expert opinion and now it’s up to you to make the most of the not-so-great idea. If the idea works, it’s an obvious win-win and you’ve made your client happy (and maybe even learned something along with way). If not, your client has no reason to be upset with you as you’ve already provided a warning that the idea may not work.

Try to say “Yes” at first - at least in principle to the desired outcome - and then do your best do steer your client to explore other options; then make a choce. You’ll become one who’s easy to work with.

DMS Photographer Sean Deren spent three weeks this August touring the southern portion of the United States. During his travels, Sean captured hundreds of photographs of everyday life in America, some of which we’d like to show you as our Project of the Month. But don’t expect to see typical postcard imagery; Sean’s eye tends to find the unique, rarely seen and away-from-the-mainstream visuals that provide a seldom-seen perspective.

Click the image above to take a tour across the southern portion of the U.S. starting in Atlanta and ending in Los Angeles.

During August, Brian Satchfield continued his work on cruise ship time lapse photography and helped set up a couple of video edit suites for clients. Robert Kildoo worked on projects for Palm Beach Media Group including shoots a the Norton Museum of Art and The Breakers. Sean Deren shot lifestyle portraits of country singer Spenser Bahr while Lance Robson continued his work on Bud Lee’s photographic images and shot photography of several professional sporting events.

As the concavity of the lens changes to reduce or enlarge the focal length, the size of the image captured on the recording medium at the focal plane becomes larger or smaller. A longer focal length creates a larger image; a shorter focal length creates a smaller image.

When the camera being used captures images on 35mm film or on a full-frame electronic sensor, each which measure 36mm x 24mm, the images captured will appear to be the same size as our eyes see those images when we use a lens with a focal length of around 50-55mm; the lens doesn’t enlarge or reduce the size of the images in the scene. A lens with a focal length of 50mm or so is considered a “normal” lens. Lenses with a focal length less than 50mm, such as 35mm, 28mm and shorter, are considered wide angle lenses. These lenses reduce the apparent size of the images being recorded and allow for more of the scene to be captured. The converse is also true - lenses with a longer focal length, such as 70mm, 135mm and longer, are said to be long lenses and increase the apparent size of the subject matter. A 25mm lens would cause objects to appear half the size as a normal lens and a 100mm lens would cause an object to appear twice the size. A lens with a focal length of 200mm or more can become cumbersome so optical engineers developed a lens system that utilizes a series of individual lenses that bend light in such a way to provide an apparent focal length longer than the actual length of the lens system. This type of lens system is called a telephoto lens.

Lenses that have a single, fixed focal length are commonly called prime lenses. They’re simple, pure and resolve pristine images. But it’s not always convenient to carry around a wide selection of fixed lenses. Thus, we have the zoom lens. A zoom lens is considered a variable focal length lens and allows the user to alter the distance of the lens to the focal plane to change the viewing angle of the subject matter and therefore the apparent size of the objects in the recorded image. A zoom lens can act as both a wide angle and telephoto lens or even as a long lens and a really long lens. A typical zoom lens may have a variable focal length such as 28-200mm although many varieties exist.

If you not using a 35mm or full-frame image sensor, look for a 35mm-equivalent description of the lens.