Digital Camera Basics - A primer

Digital cameras are confusing to a lot of new users. In this basic guide to digital camera technology we hope to try to give digital beginners at least some basis to use in deciding which digital camera is appropriate for them. When shopping for a digital camera it’s at least good to know what the basic terms like white balance, pixel, ppi and dpi mean and how they affect image and print quality. It’s also important to know the difference between things like optical zoom and digital zoom as well as the advantages and disadvantages between storage formats such as Compact Flash (CF), Microdrives, Sony Memory Stick, Secure Digital (SD), Multimedia and camera interface technologies such as USB 1.1, USB 2.0 and Firewire IEEE 1394.

Pixels

A pixel is a contraction if the term PIcture ELement. Digital images are made up of small squares, just like a tile mosaic on your kitchen or bathroom wall. Though a digital photograph looks smooth and continuous just like a regular photograph, it’s actually composed of millions of tiny squares as shown below.

On the left the full image, on the right the area in the red square magnified to show individual pixels

Each pixel in the image has a numerical value of between 0 and 255 and is made up of three color channels. So for example a pixel could be 37-red, 76-green and 125-blue and it would then look like this . If it was 162-red, 27-green and 12-blue, it would look like this . There are over 16 million possible combinations using this scheme and each one represents a different color. Computer savvy readers will note that each color in this scheme can be represented by an 8-bit number (byte), so the color of each pixel is defined by three color bytes. This scheme can be expanded, for example to use 16-bits (two 8-bit bytes) for each color. Images using three 8-bit values are sometimes called 24-bit color images. Images using three 12-bit values for color definition are called 36-bit color images, and those using three 16-bit values are called 48-bit color images.

Pixel Count

One of the main ways that manufacturers categorize their digital cameras is in terms of pixel count. What this is is the number of individual pixels that go into making each image. Today this number varies between 1 million (1 Megapixel) to around 14 million (14 Megapixels). A million pixels is abbreviated to MP, so a 1MP camera has 1 million pixels and a 3MP camera has 3 million pixels. Currently most popular consumer digital cameras have between 2MP and 5MP. A 3MP camera can make excellent 4″x6″ prints and very good 5″x7″ prints. If you intend to make lots of 8″x10″ prints, then perhaps a 4MP or 5MP camera would be a better choice. Sometimes two numbers are given, total pixels and effective pixels. Total pixels count every pixel on the sensor surface. Usually the very edge pixels aren’t used in the final image. Effective pixels are the number of pixels actually used in the image after the edge pixels have been dropped.

Typical maximum image size vs. nominal Pixel Count. See below for comments on dpi and print size

Aspect Ratio

The aspect ratio of a camera is the ratio of the length of the sides of the images. For example, a traditional 35mm film frame is approximately 36mm wide and 24mm HIGH. This has an aspect ratio of 36:24, which can equally well be expressed as 3:2. Some digicams use the same aspect ratio for their digital images. For example most digital SLR (single lens reflex) cameras have a 3:2 aspect ratio. However, video monitors typically use a 4:3 aspect ratio. For example a monitor with a 800×600 display has a 4:3 aspect ratio. With this in mind, most consumer level digicams use a 4:3 aspect ratio for their images.

Sensor Size

The size of the digital sensor element (which is equivalent to the size of the negative for film cameras) is pretty small in all consumer digicams - typically around the size of a fingernail (and a small fingernail at that!). As I said above, a 35mm film frame is 24mm high by 36mm wide but most digital cameras use sensors very much smaller than this. Here are some typical digicam sensor sizes. The “name” of the sensor is based on specification for old TV tubes used in the 1950s. Nobody is quite sure why it’s being used for modern digital sensors since the “sizes” don’t really relate in any consistent way to the actual physical size of the sensor. However these names are widely used, so it’s best to know what they are. They are often listed in digital camera spec sheets.

Relative size of various digital camera sensors	“Name”	Aspect Ratio	Width (mm)	Height (mm)
	4/3″	4:3	18.0	13.5
	EOS 10D	3:2	22.0	15.0

Most of the current small 5MP digital cameras use 1/1.8″ sensors which are about 7mm x 5mm. They have an area 25x smaller than 35mm film and about 9.5x smaller than a small sensor digital SLR like the Canon EOS 10D. You might wonder why sensor size matters and that’s a pretty complex issue. The bottom line is that, for a given pixel count, the larger the sensor (and hence the larger the area of the individual pixels) the better the image quality and the lower the noise level. While large sensor cameras like the EOS 10D can operate at the equivalent of ISO 3200 (though the image does get noisy), many consumer digicams with small sensors cannot operate above ISO 400 before the noise becomes excessive. For a full treatment why all this is so, see my article here on photo net titled SIZE MATTERS

Another factor in quality here is that small sensors tend to be of a different type than large sensors. Small sensors, and the sensors used on all consumer digital cameras, use a scheme which can read the data from the sensor in real time using a scheme called “interline transfer” and the CCD electronics control exposure rather than a mechanical shutter. Large sensors used on more expensive Digital SLRs are often of a different design known as full frame - which doesn’t refer to their size, but their design - and which require the use of a mechanical shutter. They don’t read out and the display the data in real time, only after the exposure so they can’t give real time LCD displays or record video. The advantage of this scheme is that the whole pixel area can be used to capture light while interline transfer CCDs use part of each pixels to store charge. Since smaller pixel areas generate more noise and  interline transfer CCDs are not only smaller to start with but use some of their pixel area for charge storage, their noise level is significantly higher. So the smaller interline transfer sensors in consumer digital cameras yield lower quality images than those used in higher end DSLRs, they can do more “tricks” like recording video clips and giving a live image display on their LCD screen. The lack of a mechanical shutter also makes the cameras cheaper and simplifies construction.

Small sensors mean that short focal length lenses are needed to give the same field of view as cameras using larger sensors or 35mm film. So, for example, a typical consumer digicam may need a 7mm lens to give the same view as you would get using a 35mm focal length lens on a 35mm camera. This has consequences on depth of field and means that most consumer digicams have a vary large depth of field. Great if you want everything in focus, not so great if you want a blurred background. This is covered in detail in my article here titled DIGITAL DEPTH OF FIELD

White Balance

With film you can buy “daylight balanced film” for shooting outdoors or “tungsten balanced film” for shooting indoors under normal domestic lighting (not fluorescents!). If you use daylight film under tungsten light the images will be very yellow. If you use tungsten film in daylight the images will be very blue. With film you have to correct for the “color temperature” of the light using filters or by the right choice of film.

With digital you can pick your white balance to suit your light source, so that white looks white, not yellow or blue. Normally there is an automatic setting and the camera decides what white balance setting to use. However if you know what your light source is you can usually set the camera to it and this may give better results. Most digital cameras have settings for sunlight, shade, electronic flash, fluorescent lighting and tungsten lighting. Some have a manual or custom setting where you point the camera at a white card and let the camera figure out what setting to use to make it white.

Sensitivity

Sensitivity settings on digital cameras are the equivalent of ISO ratings on film. Just about every digital camera will have settings with a sensitivity equivalent to ISO 100 film and ISO 200 film. Many will have an ISO 400 setting, but above that the images from cameras with small sensors gets pretty noisy. The more expensive digital SLRs with much larger sensors have much higher sensitivity settings. At ISO 400 they are virtually noise free and some can go as high as ISO 3200 or even ISO 6400! Very few cameras have ISO setting lower than ISO 100 because noise levels are so low at ISO 100 there would be no real advantage in a slower setting. Quite a few digital cameras have an “auto” ISO setting, where the camera will pick from ISO 100, ISO 200 and sometimes ISO 400, depending on the light level and the mode in which the camera is operating.

Digital Zoom and Optical Zoom

Most cameras have both optical zoom and digital zoom. Optical zoom works just like a zoom lens on a film camera. The lens changes focal length and magnification as it is zoomed. Image quality stays high throughout the zoom range. Digital zoom simply crops the image to a smaller size, then enlarges the cropped portion to fill the frame again. Digital zoom results in a significant loss of quality as is clear from the examples below. It’s pretty much a last resort, and if you don’t have it in camera, you can do a similar job using almost any image editing program.

Comparison of optical zoom and digital zoom

JPEG, TIFF and RAW

The size of the digital file corresponding to the image which the camera produces depends on the pixel count. In most consumer digicams each pixel generates 3 bytes of data (so called “8-bit data”). One for red, one for green and one for blue. This means that a 3MP camera, which has 3 million pixels, generates 9 million bytes of data, or 9MB (megabytes). A few cameras can generate extra data for extra quality, and some of these cameras generate files which correspond to 2 bytes of data for each color   (”16-bit”), so a 3MP camera which is capable of generating 16-bit data will produce an 18MB image file.

Now these files are pretty big and they can be compressed quite a lot without a significant drop in quality. This is where JPEG (Joint Photo Experts Group) comes in. JPEG is an algorithm designed to work with continuous tone photographic images) which takes image data and compresses it in a lossy manner (this means you do lose some information). The more you compress, the smaller the file but the more information you lose. However, you can reduce file size by a factor of 10 or so and still get a very high quality image, just about as good as the uncompressed image for most purposes. You can reduce the file size by a factor of 40 - or even more - but the image starts to look really bad!

On the left, 10:1 JPEG compression. On the Right 40:1 compression.
Uncompressed the image would look virtually identical to the 10:1 JPEG on the left.

With 10:1 compression the 8-bit files generated by a 3MP camera would be 900Kbytes in size rather than 9Mbytes, which is a big saving with little quality loss. The smaller files take up much less storage space and are much faster to send between computers or from the digital camera or memory card to a computer.

There are also lossless ways of saving files using TIFF (Tagged Image File Format) . These keep all the original information, but at the cost of much bigger files. TIFF files can be compressed in a non-lossy way, but they don’t get very much smaller. For example, compare the file sizes for the rabbit image above: TIFF files can also be used to save 16-bit data (those these files are twice the size of 8-bit data files), JPEG files can only save 8-bit data.

Some cameras offer a third option, that of saving the actual data generated by the sensor in a proprietary format. Canon calls their version of this “RAW”, Nikon call it “NEF”. These files are compressed, but in a non-lossy manner. They are significantly smaller than equivalent TIFF files, but larger than JPEGs. Typically they achieve a compression of around 6:1 using 16-bit data, so files are 1/6 the size of equivalent TIFF files. The only disadvantage of these formats is that the image must be converted to either JPEG or TIFF for most software to be able to display them. The conversion is quite a complex process and can be time consuming if you have a lot of images to convert and a PC that’s not very fast. Since the RAW and NEF formats contain more information than JPEGs (and in fact often more than TIFF files) you can  do some degree of exposure compensation during conversion to JPEG to rescue otherwise improperly exposed images. You can also make white balance corrections during conversion, so if you shot with the wrong white balance, you can fix your error.

Display, Printing, DPI and PPI

There’s lots of confusion here so I’ll try to go slowly!

When you display a digital image on a monitor, the only thing that determines the size of the image is the pixel count and aspect ratio. DPI and PPI (and I’ll explain them later) mean absolutely nothing. If your image is a 480Kbyte file which is 800 pixels wide by 600 pixels wide, it will display as a full screen image if you are using an 800×600 display. It doesn’t matter if your DPI is set to 1 or 1000 or if your PPI is set to 1 or 1000. This is 100% true as far as web display goes and as far as any monitor display goes - unless some software intervenes. For example the IE6 browser will take large images and resize them so they fit on the screen. However DPI and PPI are still ignored. A few advanced page layout programs and advanced image editors may be capable of taking DPI and PPI into account when displaying images.

So I’ll say this once again. The way you control how large an image appears on someone’s monitor screen when viewing your images on the web is by changing the pixel count.  If your original image is 1600×1200 pixels it will probably be too large to see all at once on 95% of the video monitors out there. It will also be slow to load since it will be a large file. If you want someone using an 800×600 display to be able to see your image clearly, you need to change the size to, say, 600×400 pixels (remember the browser window is smaller than the full monitor display). You change image size in software. All image editing programs can do this. Sometimes it’s called “downsampling” or “downsizing”. See your image processing software manual for details on what options your software offers.

PPI stands for “Pixels per inch” and is almost exclusively used for printing, not video display. If you take an image that is 800 pixels wide and 600 pixels high, and you print it with a PPI setting of 100 pixels per inch, the print will be 8 inches wide by 6 inches high. If you print at 200 PPI you get a print 4″ wide by 3″ high. Now the print at 200 PPI will be higher in quality but smaller. Most people seem to agree that around 320 PPI is the highest number you really need. Above that it’s very hard to see any improvement in image quality. 240 PPI is often used and even that is often regarded as high quality. Most people notice a quality drop when they go below 180 PPI.

DPI stands for “dots per inch” and is a property of a printer, not a digital image. It’s a measure of how finely spaced the droplets of ink can be in a print. However the number is a bit misleading since it’s not always measured in the way you think it might be! Printer settings of 360dpi, 720dpi, 1440dpi and 2880dpi are often found. However the difference between then is subtle at best. Most people probably couldn’t tell the difference and 360dpi usually looks great. Changing DPI does not change the size of the print. PPI controls that. DPI controls print quality (though as I said, over 360dpi you don’t see much change).

Memory

There are quite a few different (and incompatible) memory cards used in digital cameras.

• Compact Flash (CF) - The original memory card. 42mm x 36mm x 3mm. Somewhat larger than the others, but used on all high end DSLRs. Available in capacities up to 2GB. There are also miniature hard drives (Microdrives) with almost the same form factor as CF cards (CF type II, 5mm thick)) which are available in capacities from 340MB to 4GB. Microdrives used to be cheaper than solid state CF cards, though there is not a big difference today up to about 1GB. The 4GB Microdrives are actually cheaper than the 2GB CF cards though. Of course prices change pretty fast these days! Overall CF cards tend to be cheaper than any of the other forms of solid state memory - though this too could change. CF cards and microdrives contain their own disk controller, so that makes the camera electronics simpler.
• Secure Digital (SD) - Very small - about 24mm x 32mm and 2mm thick. They have a built in write protect switch to prevent accidental erasure and certain encryption capabilities of little interest to digital camera owners.
• Multimedia - Same size as SD but with less features and no encryption capability. There are some that can be used in some SD cameras but they aren’t 100% compatible with SD cards in all applications.
• Smart Media - Thinner than CF cards, but lacking an on-card memory controller. Despite the name, they’re pretty dumb!
• Memory Stick - Introduced by Sony and used only by Sony(?)
• XD - Developed and used by Fuji, Olympus and Toshiba - even smaller than SD. 20mm x 25mm by 1.7mm thick

Is there any real difference in performance? No, not really. The CF cards are the cheapest per megabyte and are available in higher capacity models than the other (of course that may change with time). Most high end DSLRs use them. The smaller cards tend to be used in the smaller consumer digicams. There’s really no reason to pick a camera with one type over another unless you have multiple cameras or other devices (MP3 players for example) which also use memory cards - then it’s convenient if they can share cards. It may also be difficult (and/or expensive) to find really high capacity cards (1GB and up) in formats other than CF, but that’s probably not a concern for most digicam users.

The following table gives the approximate number of shots you can expect to get using low JPEG compression using various pixel count cameras in conjunction with various sized memory cards at the lowest ISO speed settings of a typical camera. The exact numbers depend on how much compression the camera applies and the ISO speed used. Higher ISO settings result in more noise and noise is hard to compress and so leads to larger files and less images per card. If you’re shooting in a RAW or NEF format you can divide these numbers by 3. If you’re shooting TIFF files you’d have to divide these numbers by 8.

Approximate number of shots per memory card for various digital camera pixel counts using high quality JPEGs for storage

Digital Camera Interface

Once you’ve got the images stored in your camera on the memory card you need a way to get them into your computer! There are several ways to connect digital cameras to a PC as well as external card readers.

• Serial - The earliest digital cameras had a serial interface, but no current cameras use this since it is so slow
• USB 1.1 - USB was the first widespread high speed method of data transfer from cameras. It is theoretically capable of transfer speeds up to 11 megabits/second (note megabits not megabytes)
• USB 2.0 - A development of USB but much faster - up to 480 megabits/second. USB devices are compatible with USB1.1 ports on a PC, but will only work with them at the lower data rate.
• IEEE 1394 (Firewire) - Though this is an older interface than USB, it was originally only really used much on Apple computers. It’s capable of high speed transfer (400 megabits/second) and it’s now found on some PCs or it can be added to them via a plug-in card. More common on digital video cameras than still digital cameras.

Just about all cameras can connect to a PC, but it’s sometimes easier to remove the memory card from the camera and insert it into a dedicated card reader. Even if your camera only has USB 1.1. if your computer has a USB 2.0 you can use a USB 2.0 card reader for faster transfer. Card readers are cheap, anywhere from $15 to $40.

Buying a Digital Camera

Sad to say there are more dishonest discount camera stores than you’ll find in almost any other business. Some of the popular photography magazines are cram full of ads advertising very low prices. What they don’t tell you is that you won’t ever actually get the camera for that price. Either they will add on $75 in shipping charges or they will be “out of stock” on that model, but they will have a more expensive model available of course. Sometimes they’ll tell you that the advertised camera is plastic in made in Taiwan, but for another $50 you can get the model made in Japan. Sometimes they’ll ship you the wrong item in the hope that it will be too much trouble to send it back. Shop in the ads at the back of magazines based only on the lowest price you see and most of the time you’ll be sorry.

However, there are reputable discount dealers and photo.net is associated with a few of them. These dealers do give photo.net a small commission on sales made through their website via the links below, so please use them if theu have what you want at a good price. They’re honest, they stock what they advertise, they have low shipping charges, good prices and responsive customer service. If they didn’t we wouldn’t be associated with them and we wouldn’t recommend shopping with them.

 Casio Exilim EX-Z80Smaller, lighter, more powerful
(by Conrad H. Blickenstorfer)

In January of 2008, Casio introduced the Exilim EX-Z80. It’s a small 8-megapixel ultra compact with a list price of US$199. As one of three new members of Casio’s “Zoom” family, the EX-Z80 replaces the 7.2 megapixel Exilim EX-Z77 which we reviewed last summer (see review of the Casio Exilim EX-Z77). In its press release, Casio says that the new models, “while naturally offering significant enhancements in function and performance, focus on style with a new body shape that keeps height to a minimum and exudes a sense of premium design quality.

Subtle changes

On the surface, the new EX-Z80 model doesn’t look much different from its predecessors. For several years now, Casio digital cameras have been stylish and slender with just some minor tweaking and variations in design. Buttons and controls move around a bit from year to year, but not much. There’s not that much you can do when you have an inherently attractive and functional design that works and a LCD display that takes up much of the backside of the camera. So attention has been on details and new features. However, in this case, something has changed. The EX-Z80 is even smaller than the already very small Z77 was. Casio mentioned the “new body shape that keeps height to a minimum,” and with a footprint of just 3.53 x 2.0 inches, you could hide the new Z80 behind its predecessor, or even a credit card. With a thickness of three quarters of an inch it’s also a bit thinner (though nowhere near as thin as Casio’s “Card” cameras) and its overall volume is down by 22% compared to the 7.2 megapixel EX-Z77. It weighs less, too — 3.5 ounces bare, and a bit over four ounces with battery and card. That’s very small and light.

The metallic body is quite attractive and stylish. It’s a slender box with rounded corners and edges. The back and front are color — six are available: pale pink, vivid pink, green, blue, silver and the black shown above — separated by a silver band that goes all the way around the camera.

The controls have changed a bit. There is now a round movie record button with a red dot on it on the upper right. Just push it to start recording. This goes with Casio’s emphasis on advanced video features in its cameras. The zoom rocker has been replaced by a slender zoom ring around the fairly large shutter on top of the camera. The round 4-way navigation ring with a large “set” button in the center is unchanged, the red and green record and playback buttons, and the “Menu” and “Best Shot” buttons on the bottom are larger.

One thing that, unfortunately, hasn’t changed compared to the EX-Z77 is screen resolution. Measuring 2.6 inches diagnonally, the wide-format LCD is large enough, but it has only 115k pixel resolution. That’s not terrible, but the display isn’t nearly as sharp as that of, say, the new EX-S10 which has twice as many pixels.

Even better movie features than before

The predecessor EX-Z77 first introduced the “YouTube-mode” to Casio Zoom cameras and with that a switch to the H.264 video compression standard that reduces MPEG-4 file size more without any perceptible image degradation to the eye. This means you can record longer videos while you still essentially get MPEG-4 video quality. For the audio accompanying the video, Casio is now using the AAC audio codec used in iPods. This means you can easily watch movies made on the EX-Z80 on a video iPhod, iPhone or in Apple’s sleek iTunes and iLife’08 software. It is also a format especially suited for video-sharing websites like YouTube.com. YouTube initially ran all videos in Flash, but is switching to H.264 video, thus being inherently more compatible with the file format this Casio camera produces. The maximum video resolution has been increased to a wide-format 848 x 480 pixels, perfect for playback on 16:9 aspect ratio wide-format TVs. As far as the “YouTube” mode goes, it’s nothing magic. It is simply settings that follow YouTube recommendations for file size, running time, screen resolution, video compression and file format. You can then connect the camera to the PC and use the Casio Uploader software to easily upload the movies to YouTube. It makes things easier.

Like earlier Casios, the EX-Z80 has a “prerecord” movie feature. In this mode, the camera is recording video before you press the movie button. When you press the shutter, the camera adds the five seconds before you pressded it to your video. This means you never miss one of those special moments.

The Auto Shutter

Like the rest of the newly introduced Exilims, the EX-Z80 has “Auto Shutter” functions where the camera helps taking the best possible picture. The Auto Shutter can, for exmple, detect blur. The camera will then wait until there is no more camera shake or the subject has stopped moving before it takes the picture. Auto Shutter can also be used to take a sharp picture while panning. If you follow a car racing by with the camera, the camera will pick try to shoot the best possible picture without blur. Another use is “smile detection” in portraits. Here the camera can actually recognize a smile and then shoot the picture automatically. Face detection is all the rage these days as a must-have feature, and the EX-Z80 has it. The camera uses advanced recognition algorithms to identify and properly expose up to ten faces in a picture.

Bottomline

The US$199.95 Casio Exilim EX-Z80 is a nice update to the older EX-Z77. It now offers 8.1 megapixel resolution in a very attractive and very small package. A number of new features have been added. Auto Shutter greatly reduces blur in certain shooting conditions, there is face and even smile recognition, you can shoot wide-format 848 x 480 pixel movies, and recording in MPEG-4/H.264 format makes the files YouTube and iPod friendly. We miss a higher resolution display and the always useful auto focus illuminator, but other than that, the EX-Z80, available in six colors, is a very attractive product. We like:

• Elegant design in six colors
• Very small and light
• Auto Shutter functions reduce blur
• 30 different scene modes
• Fun movies modes and H.264/AAC recording
• 848 x 480 movies at 30 frames per second

Not so much:

• Low screen resolution
• No auto focus illuminator lamp

 Casio Exilim EX-Z100 and EX-Z20010-megapixel cameras with 4X zoom
(by Conrad H. Blickenstorfer)

Casio introduced the Exilim EX-Z100 and Z200 to the US market in January of 2008. It’s a pair of ultra-compact 10-megapixel cameras that come in a variety of colors. We’re describing them both in the same review since the sole difference between the two of them is that the Z200 includes active CCD anti shake. Why does Casio introduce yet a couple of new 10 megapixel cameras when the 10 megapixel EX-Z1080 is still available? Because of a variety of new features and a new 4X optical zoom.

A new design

The EX-Z100/200 is a new design, but closely follows Casio style themes. With a footprint of 3.66 x 2.16 inches the camera is smaller than it looks in the pictures above. The metallic body is attractive and stylish. It’s a fairly slender box that mixes rounded corners and creased edges. Four colors are available for the Z100: blue, maroon, pink and siler. The Z-200 is available in three: black, red and a darker silver. The controls clean and minimal. There is a round movie record button with a red dot on it on the upper right. Just push it to start recording. This goes with Casio’s emphasis on advanced video features in its cameras. A slender zoom ring surrounds the fairly large shutter on top of the camera. There is a round 4-way navigation ring with a “set” button in the center. Red and green record and playback buttons are above it, “Menu” and “Best Shot” buttons below. Almost everything else is done via clean onscreen menus. I should say upfront that it is not entirely clear why Casio chose to make this two separate models. There is only a U$20 price difference, with the EX-Z100 listing for US$279 and the EX-Z200 for US$299. True, the digital camera market has become very price sensitive, but it’s hard to see how the extra cost of having two different models with a total of seven different colors (four for the EX-Z100 and three for the EX-Z200) and a very slightly different body (the EX-Z200 is a small fraction of an inch thicker to accommodate the CCD shift mechanism) would be more cost-effetive than simply ship this model with the very desirable CCD shit image stabilization standard. Casio probably has its reasons, and who are we to argue with two new cameras instead of one?

What you get with the EX-Z100/200

That would be an attractive, stylish and very compact 10-megapixel camera with an excellent, high-resolution 2.7-inch LCD display. It is a wide-area format, so if you shoot, for example, video in the camera’s 848 x 480 pixel video format or the 3648 x 2048 pixel 16:9 still image format, you can see the results in the same aspect ratio, just the way they display on a wide-format TV. And, as a first in Casio’s Zoom series of cameras, you get a 4X optical zoom instead of the usual 3X. While that may not sound like much of a difference, it actually is. The common 3X zoom usually covers 36-108mm in 35 mm film parlance. This camera’s zoom is 28-112, so you can go from a substantially wider viewing angle than a standard lens to the common magnification of a 3X lens. This means you can’t get any closer than with a 3X lens, but a lot more fits into the bottom end of the lens, which is great for indoors pictures, family shots and so on. Outdoors, you can get full panoramas. In short, the 4X zoom of this camera adds flexibility.

The EX-Z100/200 also has a special Auto Best Shot mode that’s different from what is usually called “Best Shot” (i.e. shooting the same picture with bracketing exposures and then pick ther best one). Here, the Auto Best Shot actually analyzes a scene and then picks the appropriate shooting mode from the Scenes menu. At this point, the technology can pick scene modes for people, scenery, night scenes, night scenes with people, close-ups, and moving subjects. The camera actually has 39 scene modes and future models may be able to properly select most of them.

Like the rest of the newly introduced Exilims, the EX-Z100/200 has “Auto Shutter” functions where the camera helps taking the best possible picture. The Auto Shutter can, for exmple, detect blur. The camera will then wait until there is no more camera shake or the subject has stopped moving before it takes the picture. Auto Shutter can also be used to take a sharp picture while panning. If you follow a car racing by with the camera, the camera will pick try to shoot the best possible picture without blur. Another use is “smile detection” in portraits. Here the camera can actually recognize a smile and then shoot the picture automatically.

Face detection is a must-have feature these days, and the EX-Z100/200 has it. The camera uses advanced recognition algorithms to identify and properly expose up to ten faces in a picture.

In the video department you can shoot wide-format 848 x 480 movies at a full 30 frames per second. Unlike the also new EX-S1 and EX-Z80 that use the AAC audio codec widely used in Apple products, the Z100/200 records movie audio with IMA-ADPCM encoding. The video format/compression used is MPEG-4 H.264. This reduces MPEG-4 file sizes more without any perceptible image degradation to the eye and means you can record longer videos while you still essentially get MPEG-4 video quality.

As for anti-blur/image stabilization technologies, both models come with Casio’s Anti-Shake DSP (Digital Signal Processing). This is digital anti-blur, i.e. the cameras will decrease exposure time and increase sensitivity to make up for it. The EX-Z200 has, in addition, optical or “active” anti-blur technology. A CCD-Shift Stablizer compensates for camera movements and can thus reduce blur. We’ve in the past tested otherwise identical cameras where one had optical image stabilization and the other did not. Zoom and low-light pictures were markedly better with optical stabilization.

Bottomline

If you want a compact 10 megapixel camera from Casio you now have two more choices than before. If cost is the sole issue, Casio’s still available EX-Z1080 remains a good buy with a list price of US$249 and most of the same features. However, the new models add something of value, and that is the 4X zoom that allows wide angle photography. That alone is worth the EX-Z100’s US$30 price premium. Add another US$20 and you get the US$299 EX-Z200’s CCD-Shift image stabilization. We like:

• 28-112mm 4X optical zoom allows wide angle photography
• Very small and light
• Auto Shutter functions reduce blur
• 39 different scene modes
• CCD-Shift image stabilization in the EX-Z200
• Fun movies modes and H.264 recording
• 848 x 480 movies at 30 frames per second

Not so much:

• We’d prefer the AAC movie audio encoding like the other new Exilims have

 Casio Exilim Pro EX-F1Superfast camera with 12X zoom
(by Conrad H. Blickenstorfer)

The Casio Exilim Pro EX-F1, introduced in January of 2008, looks like no other Casio camera before, and it can do thing no other digital camera available to consumers can do. Casio’s corporate slogan is “Expect the Unexpected,” but even so, few would have expected the Pro EX-F1 from the company famous for its attractive little ultra-slim cameras. What is the EX-F1? A fairly large 6-megapixel camera with a 12X optical zoom and, according to Casio, the world’s fastest burst shooting performance. How fast? Up to 60 frames per second in full resolution burst mode, and up to 1,200 frames per second in high-speed movies!

Tremendous speed

We’d love to know the thought process and story behind this camera. As is, the Exilim Pro EX-F1 incorporates a newly developed high-speed CMOS sensor and a high-speed processor. In such a high-end camera you’d expect 10 or 12 megapixel, but maximum resolution is not what the F1 is all about. This is all about speed, and somehow Casio found that 6.0 megapixel worked best for what they had in mind. And what they had in mind was achieving the fastest burst shooting speed capability possible and ultra-fast movie modes. The goal was to enable capturing of split-second movement in great detail so that no important moment would be lost. Another goal was to build a camera so fast that it could capture motion that the human eye cannot see or follow. So what does that include? First, there is an ultra-high speed burst mode that offers full resolution photography at 60 images per second. A maximum of 60 shots per second can be taken and you can set the camera from one to 60 frames per second. So you can shoot all 60 in a second, or one per second for a full minute.

What’s expecially interesting is that in the high speed burst mode Casio employed a technology it has been offering in its movie modes for a while. With the “past movie” mode available in many Exilim models, you can have the camera continuously record movie, but it will only be saved to permanent memory when you push the shutter. The camera will then save the several seconds it still has in its memory from before you pushed the shutter and and then keep recording. This way you can, for example, follow a soccer game, push the shutter when a goal happens, and the camera will also save the several seconds that led up to the goal. It is a brilliant idea. Well, with the F1 you can “prerecord” still images with the ultra-high speed burst function. Up to 60 images per second, and again a maximum of 60 images, are saved in the camera’s buffer before the shutter is depressed. Once you press the shutter, all the images leading up to the event are saved. This is an incredible way to catch vital moments.

Amazingly, even the flash plays along. There are some limits, but you can take up to 20 continuous flash shots at up to seven frames per second! And there is also a (less powerful) internal LED light that allows high-speed burst shooting at between 10 and 60 frames per second.

Another cool feature is the Slow Motion View function that lets you view and capture critical moments in slow motion during still photography. It’s like magic — in the monitor the live action is displayed in slow motion. You can then review things and press the shutter to capture just the right moment.

The movie function, likewise, offers features and performance unheard of. There is a full high-definition mode where the camera records at 1920 x 1080 pixels at 60 frames per second. That is the highest currently available HDTV resolution at a frame rate speed not yet available even in the latest HDTV sets. And the F1 can directly connect to an HDTV set with a separately available HDMI cable. Oh, and sound recording is in stereo via two onboard microphones

Equally stunning are the frame rates the Pro F1 can achieve at lower resolutions. At 512 x 384 pixels you can shoot movies at 300 frames per second. At 432 x 192 at 600 frames per second. And at 336 by 96 pixels at a mind-blowing 1,200 frames per second. That means you can see things in ultra-slow motion. Oh, and there is a special “movie” button; no need to first go into an onscreen menu. For a terrific demonstration of the F1’s various high speed movie modes,

Unlike most consumer cameras, the Pro F1 offers full manual control. You can set the camera to automatic, of course, and there are Best Shot, YouTube, and Face Recognition modes and such, but for advanced shooting there are Program AE, aperture and shutter priority modes, and a full manual exposure control mode. Also handy are the camera’s bracketing modes. You can record a specified number of images with adjustable incremental changes in the EV value, the white balance, or with focus.

The other wonderful thing of the Pro F1 is its 12X optical zoom. While 12X is not the absolute highest optical zoom you can find in prosumer cameras, it certainly lets you get very close, and it does that in conjunction with all of its blistering speed. The F1 has CMOS shift anti-shake, and that certainly comes in handy when using that long zoom.

In terms of controls, this is of course a much larger and more involved camera than your typical Casio ultra-slim. It looks more like a digital SLR, and its controls are similar to those of a digital SLR. There is a viewfinder in addition to the large and high-es 2.8-inch LCD, but it is an electronic one. There are mode and continuous shooting dials, and a variety of buttons. They are all clerly labeled, though, and it shouldn’t take long to acquaint yourself with the Pro F1. In addition to buttons and onscreen menus, the camera also has a SLR-style function ring part of the big lens. Simply rotate it to adjust continuous shutter speed, zoom, or focus. Continuous shooting speed can be adjusted during continuous shutter shooting.

Bottomline

Casio loves to surprise people with the unexpected, and with the Exilim Pro EX-F1 they certainly delivered a camera that was both unexpected, and that can do totally unexpected things. Its blistering high speed burst mode, its equally stunning ultra-high speed movie modes, its ability to record full 1920 x 1080 pixel high definition video at 60 frames per second and with stereo sound, and then its 12X optical zoom with CMOS shift anti-shake — it’s just incredible. And all those amazing features do not live in a vacuum. Casio cleverly combined them with existing technologies, like their wonderful “past movie” and “pre-record” modes. The sole concern we have is that some people will look at the 6-megapixel resolution, then at the price, and move on, never realizing what a stunning camera this is. We like:

• Stunning speed both in movies and in still image burst mode
• Slow motion movies and slow motion view
• Full 1920 x 1080 HDTV recording at 60 fps, in stereo
• Full manual modes
• Strong flash that shoots at seven frames per second
• 12X optical zoom
• CMOS anti-shake

Not so much:

• 8 or 10 megapixel would have been nice.

 Olympus Stylus 850 SW8 megapixel now, several improvements, and still shockproof, freezeproof and waterproof
(by Carol Cotton Walker)

The shock and waterproof Olympus Stylus 850 SW was introduced in January of 2008 as part of the company’s big winter announcement that included no fewer than nine new consumer cameras. The 850 SW appears to be the successor of last summer’s Stylus 790 SW. There are 8 megapixel now and some new goodies, and it all comes at the same list price of US$299.99 as the 790 SW was. The stylish Stylus comes in five colors, with black, silver and yellow carrying over, and pink and cyan replacing orange and dark blue. What you get here is an attractive 8.0 megapixel camera that is shockproof, waterproof, freezeproof, sandproof, dustproof, packed with features and ready to be used virtually anywhere, including the desert, underwater, or skiing. And if you drop it, no big deal as it can survive a 5-foot fall.

What you get with the Stylus 850 SW

The Stylus 850 SW is a very compact, elegant camera you can take anywhere. It has a footprint of 3.7 x 2.4 inches and is 0.84 inches thick. It weighs under five ounces without the little Li-Ion battery, and not much more with it. The 3X optical zoom is internal, which means there is no annoying lens barrel that motors in and out. And even though the 850 SW can stand up to water, dust, sand and freezing temperatures, it’s still a full-function digital camera with all the features you expect from a modern point & shoot compact. The 850 SW is easy to use right out of the box. In the back you find a mode dial that lets you select automatic, image stabilization, guide mode, movie, playback and favorites, as well as scenes. Below the mode dial is the ubiquitous four-way navigation pad with an “OK” button in its center. Four additional function buttons bring up the onscreen menu and cycle through often used functions.

Features

As stated, despite being a “specialty camera,” the 850 SW has a variety of nice features that make it suitable for everyday picture-taking, and not just trips outdoors. Like almost all new consumer digital cameras, the Stylus 850 has a face detection mode. This means that the camera is able to find a face or even multiple faces in a picture and make sure that they are in focus and properly exposed. That even works when people are moving.

Digital image stabilization uses higher sensitivity and higher shutter speed to reduce or eliminate blurriness in pictures. It doesn’t however, have mechanical sensor shift image stablization which would come in especially handy for underwater shooting.

The TruePic III Image Processor, developed for digital SLRs, delivers more vibrant colors, smoother edges, less nose and higher overall speed.

Olympus equipped the 850 SW with its Shadow Adjustment Technology that analyzes shots of subjects in front of bight backgrounds and then exposes things properly. In essence, it compensates for extreme contrast where the shadow areas on the foreground subject are underexposed and lack visible detail.

The Perfect Shot Preview feature displays the effects of various settings including zoom, exposure, white balance and metering - on the LCD so you can select the proper settings and effects

The camera also has an LED Illuminator that works like a mini-flashlight on the front of the camera to enhance focus and exposure for macro shooting. It is also great for underwater close-ups where light is scarce. The LED also works in conjunction with the Bright Capture feature (brightened LCD preview for better composition in low light) to help illuminate a subject when taking low-light portraits.

While the 850 SW does not have any manual modes, there are 27 “scene modes” in addition to auto: portrait, landscape, landscape + portrait, night, night + portrait, sport, indoor, candle, self portrait, available light portrait, sunset, firework, cuisine, behind glass, document, auction, shoot & select 1 and 2. beach and snow, underwater wide 1 and 2, and underwater macro. New is a pre-capture movie mode where the camera records but only commits to storage once you push the shutter. That way you are certain to capture the seconds leading up to an event.

Shoot & Select lets you take sequential pictures by holding down the shutter. The pics then show up as sort of a filmstrip and you can select which you want to keep and which you want to discard.

“Guide” sort of guides you through various scenarios and sets the camera properly. This mode also lets you preview a scene through a multi-frame window that shows how the picture looks with four different settings. You then pick what suits you best.

The Stylus 790 SW predecessor, like other Olympus cameras, had both a macro and a super-macro mode. The macro mode goes from eight inches to infinity whereas super-macro goes from 2.8 inches to a bit over two feet. The website did not reflect that and the 850 specs also do not show it. We suspect the 850 does have a super-machro mode. The Stylus 850 SW has a 640 x 480 movie mode with sound, and it shoots at 30 frames per second for lifelike video. We don’t know if the camera still has the 10 second limit for recording in fulle VGA format. Sound has never been a strong side of Olympus consumer cameras. The 850 SW has a Shooting Assist function for voice recording but we’re not sure if that includes a full voice recording mode. You can attach short sound clips to still images.

New and improved

Compared to the 790 SW, which likely is its predecessor, the 850 SW has some welcome new features. There is the pre-capture movie mode discussed above. This means you’ll never again miss a once-in-a-lifetime moment in a movie. Just record, and the the big event happens, push the button. The camera will then store the seconds leading up to the event.

Sequential shooting is twice as fast. You can now shoot seven frames per second at 3 megapixel resolution. At full resultion (8MP), you can shoot six frames in one second intervals.

There is an in-camera panorama mode that lets you capture three images and then stitches them together to create a panoramic picture. As you pan, special markers shows up on the display. Align them to take the next picture.

The flash range has been extended to 17.4 feet in wide mode and 12 feet in tele mode.

You are no longer limited to the often somewhat hard-to-find xD-Picture cards. The 850 SW comes with a special adapter so you can use microSD cards as well. Internal storage remains a meager 15MB.

Shock and waterproof

Unlike most digital cameras, the 850 SW can take a beating. Thanks to a durable metal body, floating circuitry inside, and shock-absorbing construction, it is rated to survive 5-foot drops (we recommend the optional US$15 silicon clear skin). The camera is also waterproof thanks to a combination of seals and gaskets. The 850 SW is rated waterproof to a depth of ten feet, which makes it suitable for playing in the pool, rafting, snorkeling, freediving and perhaps even shallow scuba diving (it can likely handle 15 feet, though we do not recommend it). For serious diving, there is the optional US$279.99 PT-041 underwater housing rated 133 feet.

Freezing temperatures do not affect this camera as it is freezeproof down to 14 degrees Fahrenheit. So it’s a perfect companion for sledding, skiing, snowboarding and such.

Bottom line

The attractive ultra-compact water, shock and shockproof 8-megapixel Stylus 850 SW is perfect for those who love to take their camera outdoors without having to baby it. The camera can take a beating and you can even use it underwater, down to a depth of ten feet. It has the same features as standard consumer models, which means it is useful anywhere and not just as a sports camera. We like the internal zoom, the excellent 2.5-inch LCD with its very wide viewing angle. Keep in mind that if you want a camera you can take diving without a housing or one that is crush-proof as well, you need the older Stylus 770 or the new Stylus 1030. But if you just want something waterproof, the less expensive 850 SW is just right. If you’re comparing it to the Stylus 790 SW, you get more resolution, the pre-capture movie mode, a stronger flash, the ability to use microSD cards instead of just xD-Picture cards, faster burst mode, and in-camera panorama shooting.

We like:

• Attractively styled sports and outdoor camera
• Snorkeling possible with 10 feet depth limit
• Inherent waterproofing provides peace of mind when handling in/around water
• Can survive 5-foot drops and 14 degree temperature!
• Superb wide-angle, high-res 2.5-inch LCD
• Pre-capture movie mode
• microSD adapter included
• Very good underwater macro mode
• LED illumination
• Optional deepwater housing

Not so much:

• Strictly point & shoot