DIY Network

Zoom Photography: Optical and Digital Zoom From "The Whole Picture" episode DTWP-108

	The zoom capabilities of your camera are likely displayed on the camera itself. This digital instamatic is features a 3x zoom.
	This more advanced digital-camera comes with a 10x zoom lens.

NOTE: Images on this page may be enlarged for enhanced viewing simply by clicking on them.

Zoom photography can open up a whole new world in your picture-taking, including the ability to "get in close" on elusive subjects and some creative options for isolating your subject by manipulating focus and depth-of-field. The Whole Picture host Erin Manning explains how to use your camera's zoom features the right way in order to get some impressive results. She also explains the important difference between optical and digital zoom.

In this lesson, Erin instructs one of her students to help him improve his results when photographing birds at his birdfeeders and in his backyard. For the purpose of this lesson, more stationary "stand ins" were used in place of live birds.

Materials used in this episode:

Digital camera with zoom function
Camera owner's manual
Tripod
Computer with image-editing software installed

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Figure A

Getting the Most Out of Zoom

Despite the downside of using a zoom lens (e.g., the possibility of "magnifying" problems such as blurring and camera-shake), having telephoto and zoom capability offers you the ability to gain more than you lose. These capabilities offer the photographer an set of tools that expands the creativity and potential for getting compelling pictures. Most digital cameras offer a given amount of optical-zoom range, such as 3x to 6x. This refers to the camera's built-in capability for magnifying or "zooming in on" the subject by means of varying the lens optics (figure A).

10x vs. 3x zoom.

When it comes to telephoto and zoom photography, start with the right equipment. When purchasing a digital camera, buy the highest level of optical zoom you can afford. For serious telephoto photography, such as for photographing wildlife, you may want to look into cameras offering powerful optical-zoom capabilities, such as 10x or more. Many professional photographers use digital SLR cameras that permit interchanging of lenses, thus allowing the photographer to select between wide-angle, regular, telephoto or variable zoom lenses.

Don't make the "all or none" mistake that many amateurs photographers make. Novices tend to simply stand in place, zoom all the way in and snap the picture. Pictures taken like that typically end up with a lot of clutter and no distinguishable point of interest in them (figure B).

No matter what level of zoom you have, to get the most out of your lens, try moving in as close to your subject as possible before using your zoom. Then use the zoom lens to select a small part of your scene that you want to be the point of interest. That's one way to isolate your subject so that it stands out from the distracting objects that may be around it (figure C).

Figure B

Figure C

Another way to isolate your subject is to take advantage of the zoom lens' reduced depth-of-field. When the depth-of-field is significantly reduced, the area in focus is minimal. Use the reduced depth of field as one of the composition elements in your pictures. The softly focused background will help accentuate the point of interest you selected.

Keep in mind that, with the limited depth of field, focus is more crucial. When you focus the camera, be sure that you focus on the most important part of the subject and then readjust your framing before taking the picture.

Getting the most out of your zoom lens is easy. You just have to understand the ins and outs of taking great zoom pictures. The zoom gives you the unique ability to isolate your subject so that you get the picture you want. But remember, everything is magnified including the things you don't want to see.

Optical vs. digital zoom.

More About Optical vs. Digital Zoom

On digital cameras, there are two types of magnification that may be used. One is optical, achieved in much the same way as traditional photography--through the optics of the lens. The other is digital zoom, which is essentially just a digital magnification trick that the camera does internally by "enlarging" and "cropping" the image--much the same way you might enlarge and crop an image using a computer and image-editing software. These two methods may be used singly or in combination, and the packaging and marketing info that comes with most digital cameras will list them separately and as a "combined" total, ostensibly indicating the maximum amount of magnification you can achieve with that camera.

It's important to recognize that the digital-zoom feature won't give you the telephoto effects with the same level of quality as the optical zoom. The best way to see the difference between optical and digital zoom is to take a picture at the maximum length of your optical zoom. Then, continue to zoom in until your digital zoom kicks in. Usually the camera will have some indicator to let you know when the digital zoom is being employed..

	Figure D
	Figure E

Take the same picture at the maximum digital zoom and then compare the two pictures. You'll quickly see that the camera chose the picture's cropping and created some level of distortion or pixilation where the picture was electronically enlarged (figure D; click on the image to see the pixilation effect).

If you have to use the digital zoom, keep it at the absolute minimum and use the highest resolution your camera offers. But, if you don't have to use the digital zoom, do what the pros do. Turn it OFF.

Turning off digital zoom is easy. Just navigate to the digital zoom function in your camera's menu system (figure E) and choose "OFF." Then put the camera back into CAMERA MODE. Check to ensure that the digital-zoom does not come back on automatically.

If you're planning to transfer your pictures to your computer, and you have image-editing software available on that computer, there's little or no reason to use your camera's digital zoom. If you want, you can achieve the same results after the picture is shot, and likely with a wider and more sophisticated range of options and greater degree of control, on your computer--as opposed to with the digital zoom feature of your camera.

In the lesson that follows, Erin talks about how to crop and resize an image to achieve the effect of digital-zoom, but by using your computer's software rather than a camera setting.

Zoom-Photography Recap

Getting close to your subjects is easy when you know how to use your zoom lens. It allows you to isolate the things you want in your pictures. But don't get tricked by digital zoom. Give yourself the choice and avoid digital zoom by turning it off. That way when you get home, you still have the control over your pictures.

RESOURCES :

PC Photo magazine
Website: www.pcphotomag.com
Online version of the magazine devoted to digital photography and related technologies.

The Complete Idiot's Guide to Digital Photography
Model: 002864235X
Author: Steven Greenberg
Order this book from Amazon.com.
Prentice Hall
Paramus, NJ 07652

Digital Photography For Dummies
Model: 0764506463
Author: Julie Adair King
Order this book from Amazon.com.
Hungry Minds, Inc.

Complete Digital Photography
Model: 1584500077
Author: Ben Long
Order this book from Amazon.com.
Charles River Media
Website: www.charlesriver.com/