Those Amazing 8s; A New Breed Of Digicam Changes File Size Expectations

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Particularly when traveling or involved in some outdoor activity, a compact camera with built-in lens is more convenient and practical than an SLR system. If you want great versatility as well as images with ultrahigh resolution, consider one of the eight-megapixel cameras.
Photos © 2003, Peter K. Burian, All Rights Reserved

Until recently, a 6-megapixel sensor was considered to be the ultimate available in a digital camera with built-in lens, but that changed suddenly when five manufacturers released 8-Mp models. Boasting numerous advanced features, through the lens viewing and compatibility with optional flash units, each of these cameras cost about the same as a 6-Mp digital SLR body alone; the built-in wide angle to telephoto zoom lens is a bonus. Because of their versatility and high-resolution capabilities, some retailers recommend these cameras as an alternative to an SLR system.

But how do these new cameras stack up? In order to make that determination, I tested all five models: the Canon PowerShot Pro 1, Konica Minolta DiMAGE A2, Nikon Coolpix 8700, Olympus C-8080 and Sony DSC-F828. Similar in certain respects, all are very well specified, and include an electronic viewfinder and employ the same Sony ICX456 CCD sensor. The differences are worth noting, too. In addition to varying features these cameras differ in speed, convenience of operation, in the quality of their electronic viewfinders (EVF) and in the image quality produced by each manufacturer's own processing engine. As well, the Sony DSC-F828 employs a four-color filter (intended for more accurate color reproduction), while the others use the traditional three-color filter. The effects of these differences are discussed in the following text and in our Ratings chart.

This scene was one of several (of varying levels of darkness) that I used for testing digital noise levels at ISO 400. The results produced by each camera should be visible in the small sections of all five images reproduced here. (All at ISO 400 at f/4 at 60mm equivalent; not all images made at the same time.)

Image Sensor Issues
An 8-Mp sensor is certainly impressive and all five cameras can generate images with 3264x2448 pixel resolution, surprisingly high for a compact camera. Problem is, the CCD sensor is also small: 8.8x6.6mm, tiny when compared to the 23.7x15.5mm sensor in the Nikon D70, for example. Consequently, the 8 million photodiodes or pixels are miniscule. The pixel pitch--distance from the top corner of one pixel to the next--is only 2.7x2.7 microns, much smaller than the typical 7.5x7.5 microns in the 6-Mp sensors used in D-SLRs. (A micron is one millionth of a meter.)

That raises a concern because very small photodiodes are less sensitive to light. They cannot record as much detail in both highlight and shadow areas in contrast scenes and they produce more digital noise (colored specks caused by electronic interference) in shadow areas, particularly at high ISO settings. On the other hand, a highly effective image processing system can produce quite "clean" images with a wide tonal range; these aspects were important considerations during my testing.

8-Mp Canon.

8-Mp Konica Minolta.

8-Mp Sony.

8MP Olympus.

8-Mp Nikon.

In spite of the theoretical problem, I found that most of the cameras produced images with good highlight and shadow detail. The Coolpix 8700 rated lower but only because of its higher contrast. Digital noise was not a problem in most outdoor shooting with any of the cameras. At ISO 100 and below, only one camera produced images with apparent noise and that was detectable only in shadow areas at high magnification. At ISO 200, noise was certainly visible but not objectionable, especially in images without a lot of shadow areas; regardless of the camera, my best ISO 200 images made for beautiful 8.5x11" prints. By ISO 400 however, digital noise is obvious in images made with four of the five cameras. Before making large prints of exhibition quality from ISO 200 or 400 images, I would recommend using Noise Ninja, a highly effective noise reduction program. ($29;

Performance And Image Quality Evaluation
Although each camera produces virtually identical resolution, every model has a unique personality as well as its own pros and cons. Lack of space precludes a full review, but I can provide the following summary of each model, with additional specifics in our chart.

Canon PowerShot Pro 1: A bit heavy but surprisingly compact, this one is nearly intuitive in operation, thanks to several SLR-style analog controls. Incredibly fast, reliable and versatile, it's competitive with some D-SLRs for serious photography, missing only a TIFF recording mode, faster autofocus response in low light and a full tracking focus system. Still, the AF system is fast; combined with high-speed continuous framing and recording, the Pro 1 was ideal for capturing a fleeting photo opportunity or a very long series of high-res JPEGs at 2.5 fps. The electronic viewfinder offers very high resolution for a crisp sharp view and it's quite bright in low-light conditions. Images made at ISO 400 exhibit prominent noise with a slightly coarse pattern, moderately high sharpness and good definition of intricate details.

Konica Minolta DiMAGE A2: A fairly large camera with an oversized handgrip and convenient mechanical focus ring, the A2 is also very convenient to operate thanks to many analog controls. Loaded with advanced capabilities, this one includes two valuable extras not available with the others. The Anti-Shake (stabilizer) system allowed me to make sharp images without a tripod in low light while the true tracking autofocus (not merely continuous) makes this camera more useful than the others for action photography. I judged the EVF as exceptional; aside from ultrahigh resolution, it was bright in low light, though the image turned to monochrome at times. My ISO 400 images are slightly soft and quite smooth; digital noise is prominent but the "grain" pattern is quite fine and intricate details are well defined.

All five cameras employ an electronic (not optical) viewfinder, a small LCD monitor that provides through the lens viewing. Some of the viewfinders are better than others, particularly in terms of brightness level in low-light photography, as discussed in the text and the Ratings chart. (Minolta DiMAGE A2; JPEG Fine mode; flash.)

Nikon Coolpix 8700: The smallest and lightest of the 8-Mp cameras, this one boasts the longest focal lengths; that feature, plus fast autofocus, was useful for shots of wading birds in Florida. However, the Nikon does not offer the wide angle of view possible with the other cameras. I found this model to be the least intuitive in its overall operation; it also required more frequent access to the electronic menu. After a thorough study of the owner's manual, the camera proved to be quite fast and highly versatile. It was quick in startup, in focusing even in low light, in continuous shooting (at 2.5 fps) and in image recording, so I rarely missed a photo opportunity. Its EVF is quite acceptable in dim light but in bright outdoor conditions, it produces blooming, a bright color pattern. Digital noise is obvious in ISO 400 images, with a slightly coarse pattern, accentuated by high sharpness/contrast, but intricate details are well defined.

Olympus C-8080: A moderately large and heavy model, the C-8080 starts up quickly and focuses almost instantly with a dual autofocus system that's very reliable, even in low light. Its EVF proved to be about average in brightness. This camera is particularly versatile offering more choices than the others in autofocus, ISO, image size and light metering options. I missed only the longer focal lengths available with its competitors. While continuous framing was adequately fast (1.6 fps), image recording and playback were slower than average. Digital noise is exceptionally well controlled in ISO 400 images, making the C-8080 the leader in this regard. My JPEGs are a bit soft, sometimes lacking in texture; still, most intricate details are well defined and the images respond well to sharpening in Photoshop.

Particularly at ISO 50 and 100, the Canon PowerShot Pro 1 produced images of excellent quality with high sharpness. Color balance, saturation and exposure were generally close to perfect. (ISO 100; at f/3.2; Superfine JPEG; "Shade" white balance; continuous AF.)

Sony DSC-F828: The largest and heaviest model, the DSC-F828 offers a professional look and feel, many analog controls for ease of use, an EVF that's quite useful in low light, plus reliable autofocus with good responsiveness even in darkness. The 2.5 fps burst mode allowed me to shoot long series of a (not particularly fast) dog sled race. This is clearly a serious photographer's camera with some unique features and a very convenient mechanical zoom. At low ISO, image quality is excellent, especially in color rendition, but digital noise could be more effectively controlled. By ISO 400, noise is very obvious with a coarse pattern, accentuated by high sharpness, and it begins to obliterate the finest intricate details.

Final Assessment
How do these compact 8-Mp cameras compare to the 6-Mp digital SLR cameras? As you might expect, the higher pixel count produces greater resolution, but the D-SLR cameras, with their larger sensors and photodiodes, generate superior overall quality. Because the data is cleaner, the 6-Mp files can be enlarged to a greater degree in Photoshop without a significant loss of quality. My very best 8-Mp low ISO images allowed me to make very nice 11x15" prints, while the 6-Mp images from the SLRs produced 12x18" prints of similar quality. When starting with ISO 400 images, the D-SLR cameras' low noise advantage offers an even greater benefit: The 12x18" prints are comparable to 10x13" prints made from 8-Mp images.

In terms of specifications, some of the 8-Mp cameras are quite competitive with the D-SLR models but the latter generally offer even higher speed, faster recording and more advanced autofocus systems, more useful for sports and action photography especially. Naturally, the ability to use a vast range of interchangeable lenses also gives the D-SLR cameras an edge.

On the other hand, not all photo enthusiasts need the benefits provided by a D-SLR system. If you generally use ISO 50 or 100 for your serious work, rarely shoot action subjects, do not need ultra-wide or super telephoto lenses and do not make 12x18" prints, you should be fully satisfied with one of the 8-Mp cameras. In order to decide which model would best suit your own specific needs, compare specifications on the manufacturers' websites, including information about compatibility with optional flash units and a wide angle and telephoto lens adapter. Select the right camera, add an accessory to increase its versatility, and you'll be well equipped for a great deal of serious photography.

A long-time eDP and Shutterbug contributor, stock photographer Peter K. Burian is the author of a new book, Mastering Digital Photography and Imaging. ($21 through online bookstores.) Covering all aspects of the topic--the technology, equipment and techniques--this book provides 270 pages of practical advice for photo enthusiasts.

One of the fastest 8-Mp cameras, the Sony DSC-F828 allows for shooting a full seven high-resolution frames in a series at 2.5 fps. While its continuous autofocus system was not designed for tracking fast motion, many of my images of this race were quite sharp. (At ISO 64; f/8 at 1/400 sec.; JPEG Fine mode; image cropped.)

The extra long focal length available with the Nikon Coolpix 8700 was often useful for distant subjects. However, the camera produced images with very high contrast, problematic in bright conditions particularly with light toned subjects. (At 280mm equivalent. f/4.2 at 1/100 sec with camera braced on a tree branch; JPEG Fine mode.)

At ISO 400, the Olympus C-8080 produced smooth images; while digital noise is visible, the pattern is very fine. The slight image softness is easily corrected with Unsharp Mask in Photoshop, if desired. (At f/3.2; 1/80 sec; flash; ISO 400; JPEG Fine mode; underexposure corrected in Photoshop but no sharpening applied.)

The only 8-Mp camera with an Anti-Shake (stabilizer) device, the Konica Minolta DiMAGE A2 was very useful when shooting handheld in low-light situations. In order to clearly illustrate the value of the Ånti-Shake system, I used an extremely long 1 sec exposure for this image and it's surprisingly sharp. (At 200mm; f/8; JPEG Fine mode; image cropped.)

While the image quality produced by each camera differed, all five generated many superb images, suitable for making a fine 11x15" print. As the small section of this image--sized for making an 11x15" print at 280dpi--indicates, resolution and sharpness are excellent. (JPEG Fine mode; ISO 400; f/4.2 at 1/100 sec; at 280mm equivalent; fill flash; Nikon Coolpix 8700.).

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