Sharpen Your Image
Tips For Sharper Pictures With Your Digital Camera

When critical focus is important, I'll never rely on the AF system to automatically set focus for the most important subject area. With this llama, the AF system always focused on the tip of the snout--instead of the eye--until I used the technique described in the text to achieve the desired results. (Canon EOS D60; ISO 100; fill flash; Unsharp Mask applied in Photoshop.)
Photos © 2002, Peter K. Burian, All Rights Reserved

All too often, friends with a new digital camera complain that they cannot get sharp pictures. Their images look fine on a computer monitor, but they're not tack sharp when printed in 8x10" size. Frankly, any of today's better 3 or 4-megapixel cameras should produce images that will make for a very crisp and snappy print. If you're not fully satisfied with your own results, read on. With the right techniques and settings, you can improve your success ratio of technically excellent images.

Use The Right Shooting Techniques
Whenever shooting with the camera handheld, our natural body tremors create shake that can produce unsharp images: blurred because the camera was not perfectly steady. For sharper pictures, hold the camera steady, with two hands, and use the proper stance: legs spread to a comfortable distance, elbows tucked in close to your body, and camera pressed against your cheek or forehead. Holding the camera away from your body is a recipe for blurry pictures, so avoid using the LCD monitor for composing your images. If you must use the monitor, select the ISO 200 setting for faster shutter speeds to reduce the effect of camera shake.

In JPEG capture mode, most digital cameras produce the best resolution and sharpness when you select the highest quality/lowest compression settings. You'll need some high capacity memory cards to hold all of the large image files, but the price of these accessories has dropped to an affordable level. (Nikon Coolpix 5000; Fine/Large JPEG capture mode; Hoya super multi-coated polarizer; Unsharp Mask applied in Photoshop.)

In very low light, when flash is not practical--inside a cathedral, for example--use a very rigid tabletop tripod as a firm support for the camera. For nearby subjects, use flash to help "freeze" any slight camera shake and produce better fine delineation of your subject. Flash can also be useful to stop motion if a nearby subject is moving slightly.

Avoid High ISO Settings
When you want fast shutter speeds--to freeze any blurring from camera shake or subject motion--you may decide to set ISO 400. This may produce sharper pictures, but overall image quality will suffer. Try some test shots with your own camera at each of the available ISO settings. You'll probably find that the high ISO settings produce a lot of digital artifacts, lower resolution, and less clearly defined details. Unless your camera is an exception to this general rule, stick with the lower ISO levels unless there is no other way to get a sharp picture in low light.

Use The Right Focusing Technique
Many cameras include a wide focus detection zone, or several focus points across the viewfinder. That feature is great for quick shooting with an off-center subject. But it can make it difficult to set focus on an important area: a person's eye, for example. For pinpoint accuracy, switch to a single focus sensor if your camera offers that option. Point the lens at the desired area and set focus with slight pressure on the shutter release and wait for the focus confirmation lamp in the viewfinder or the LCD monitor. While recomposing to take the final picture--using the proper camera holding technique--keep focus locked with light pressure on the camera's shutter release button.

Even cameras with a zoom lens of superb optical quality will produce flare in certain conditions: extremely bright backlighting, in this case. To minimize or prevent this problem, try some of the techniques discussed in the text.

Use The Best JPEG Options
Most cameras include several options for JPEG image quality and for JPEG compression. Select the highest quality level --employing the most pixels--often called "Super Fine" or "Fine." Then select the "Large" setting, to make image files with a very low rate of compression. If your camera offers only a few image quality options--Best, Better, and Good, for example--select the best setting. While the large files take up a lot of space on your memory card, they also offer the best resolution and the most impressive definition of fine detail.

It may be tempting to use the "Small" option to maximize the number of images that your memory card will hold. Unless your cards are almost full, avoid that temptation, because the very high compression rate will degrade apparent sharpness and introduce digital artifacts. Buy a high capacity memory card instead and use the best image recording options. If your camera offers a RAW or TIFF recording mode, try one of those for superlative image quality in large prints. While image recording time may be long, some subjects are so important that you'll happily wait an extra 15 to 30 seconds.

While other technical and creative aspects are important too, most pictures benefit from high sharpness and great definition of intricate detail. There's no need to spend over $2000 for a digital SLR camera if you want to make sharper images. Simply use a camera with a high quality lens plus the right shooting techniques and settings, and make sharpness adjustments in image editing software. (Sony DSC F-707; Unsharp Mask applied in Photoshop.)

Shade The Lens
On sunny days, stray light can strike the lens and produce flare: a bright haze effect that degrades contrast and apparent sharpness. If your digicam accepts a lens hood accessory--or a tube that's intended for mounting filters--order one and use it on sunny days. Avoid strong backlighting and sidelighting by changing your shooting position. Or move around until you find a tree, a branch, or a building that casts a shadow; use that to shade the lens. You can also ask a friend to hold a cap close to your lens so it casts a shadow on the front element.

Insist On High Optical Quality
A $600 camera with 3x optical zoom will usually include a better lens than a $249 model. If you're serious about digital photography, do some research about the quality of the lens in the cameras that you're considering. As a start, look for models with "aspheric" or "low dispersion" glass. If your camera accepts filters, you may want to buy a polarizer. This accessory is great for enriching blue skies and for wiping glare from reflective surfaces--buildings, foliage, glass, cars, etc.--for deeper, more vivid colors. A polarizer can also cut through haze, creating images with greater apparent sharpness. When buying a polarizing filter, stick with a brand with an excellent reputation and buy a model that's "multi-coated" or "super multi-coated" to reduce the risk of flare.

The Unsharp Mask filter--available in all Adobe Photoshop programs--is the best option for increasing image sharpness. This feature offers fine control over the exact amount of "sharpening," and that can differ from image to image depending on the effect you want to achieve. If you're not satisfied with the results produced by your first attempt, simply use the Step Backward command and try again with different Unsharp Mask settings.

Select The Right Sharpness Level
Many cameras include a control for selecting the desired sharpness. While high sharpness can be desirable, think twice about using the highest setting. This typically produces excessive sharpening: with an artificial effect and a "halo" around subject edges. The medium or default sharpness level is generally the most appropriate, although you may wish to use the Low setting if your camera tends to produce an unnaturally high sharpness level. Lower sharpness can also be desirable for portraits and wedding photos for a softer, more flattering effect.

Need A Bit Of Extra Sharpness?
After converting your JPEG images to TIFF format, complete all image enhancement steps in any Photoshop program and re-size the image to the intended print size, using the Image>Resize>Image Size tools. Set the resolution to at least 240 pixels/inch, or up to 300ppi, if that does not increase the image file size by more than 50 percent. A greater increase can really degrade resolution, sharpness, and overall image quality. In the Image Size screen, be sure to check the Resample Image box and select the Bicubic option, a sophisticated re-sampling or interpolation system that increases the number of pixels for a larger image file. Finally, access the "Unsharp Mask" tool (under Filters) for ultra fine control over the exact level of sharpness.

As a starting point, try the following settings with images from a 3 or 4-megapixel camera: Amount 60, Radius .06, Threshold 3. While using Unsharp Mask, magnify the image on your monitor to 100 percent. Check the effect of any sharpening. If it is inadequate or excessive, use the Step Backward option and try a slightly different combination of settings. You can also find after-market software, such as nikSharpener Pro! Ink Jet Edition www.nikmultimedia.com. This program analyzes every image and applies just the right amount of sharpening for the intended print size, without degrading clarity, detail or colors.

Final Recommendation
The ability to enhance images electronically may seem like a wonderful way to make every photo razor sharp. I wish it were that simple. In truth, there's no software that's really effective with images that are blurry. While you can improve images with slight defects, it's impossible to correct major problems caused by poor technique or inappropriate settings. If you're serious about your pictures, pay attention to all of the image-making steps and the extra effort will pay dividends in improved technical quality.

eContact
Cerious Software Inc.
(704) 529-0200
www.cerious.com

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