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Bob Wade
Selecting a Digital Camera

Let me preface this discussion with a comment. These are my personal opinions and I’m sure there are many who will disagree with particular points. That’s fine. Differences in opinion are what keep all those manufacturers in business. Wouldn’t it be a dull world if everyone wanted the same camera, lived in the same place, drove the same type of car and ate the same kind of food?

As obvious as it sounds, the first step in selecting a digital camera is to decide what you want to do with it. Are you someone with no knowledge of photography who wants a camera for snap shots produced as small prints and an occasional email? Are you someone with (or someone with a desire to develop) a basic knowledge of photography and would like a camera that allows some degree of creative control and can produce an 8 x 10 print when desired. Or maybe you are an advanced amateur and want a camera capable of professional results of the highest quality. Decide what you want to do and then look at the following camera characteristics to find the one that best meets your needs.

How many pixels do you need? Ask 10 people and you will probably get 10 different answers. Personally, I would consider 3 megapixels to be the minimum and would be even happier with 5 or 6. Just remember, one of the primary advantages of digital photography is the ability to easily modify, enhance and improve your original image. Don’t be surprised if, after a little creative cropping to improve the original composition, your 4 megapixel image ends up as a 1 megapixel image.

Cameras with lower resolution are capable instruments and provide nice drugstore sized prints and email photos. Their main drawback is that they lack the capability to go much beyond that. They are usually "point and shoot" and do not offer the user an opportunity to change the settings chosen by the camera’s automatic exposure system. This will produce a good photograph under most situations but will not allow manual adjustments for unusual conditions or for creative results. But that really doesn’t matter if that meets your needs. You may also find that the camera that meets your needs today will be quickly outgrown as your interests grow.

There are some cameras that list interpolated resolution without so stating. They will advertise a "6 Megapixel" camera which has a sensor that only captures 4 Megapixels and derives the additional pixels through interpolation. At least some of these cameras produce great results, I would just be happier if they were more truthful in stating the pixel resolution of their sensors.

Lens…The three most important characteristics of a lens are its optical quality speed and focal length.

Optical quality is difficult to assess. You are probably safe in assuming that you pretty much get what you pay for and no major camera maker will knowingly attach their name to a bad lens. Just remember that it costs the manufacturer more to build a faster lens with a greater zoom ratio and that those costs are passed on to you.

Lens speed is determined by the amount of light it can transmit to the film or digital sensor and expressed as a number representing its maximum aperture. The lower the number the "faster" the lens. I would consider a number of "2.8" or lower to be reasonably fast and one with a number of "5.6" to be slow. Faster is better.

Focal length of a lens is expressed as number in millimeters. This can be used to determine the zoom range but is otherwise useless. We usually think of a zoom lens in terms of the degree of magnification it can provide but what we are really interested in is the angle of view it provides at its different focal lengths. Since the camera’s angle of view for a given focal length is dependent on the size of the sensor; the focal length doesn’t tell us anything. That is why most camera statistics quote "the 35mm equivalent" focal lengths. Since the size of a 35mm film frame is a constant this is the factor you should consider when evaluating a lens and is directly comparable with other cameras.

A Macro function is also a nice feature. This allows you to place your camera much closer to the object and to still be able to focus. Very nice when photographing flowers or very small objects.

What should we look for? A lens with a 3X zoom with a 35mm equivalent focal length of 28mm to 80mm and a maximum aperture of F:2.8 would represent a nice combination of price and performance. These are not hard and fast rules, just guidelines. A 24mm on the wide end would be even better but much harder to find. A number of 105mm or 200mm on the telephoto end would also be great. The problem is trying to find a lens with a focal length of 24mm to 200mm at a reasonable price. You should also be aware that the maximum aperture on almost all reasonably priced zoom lenses are variable. They get smaller (slower) as the focal length increases. That lens advertised as a "2.8" may actually be one at its shortest focal length but may be a relatively slow "5.6" at its longest focal length.

Also beware of the "digital Zoom" features quoted for most cameras. This is a useless feature and provides no real advantage. Just something the marketing department dreamed up to make you think you are getting something extra. I have also noticed that some cameras are now offering "in camera cropping". This seems like a "digital Zoom" to me and is just as worthless.

Another desirable feature would be a threaded lens front to allow mounting threaded filters and lens hoods. Filters aren’t as important as they used to be with film but are still very useful. I highly recommend a UV or Skylight filter for protection if nothing else and a polarizing filter and neutral density filter for creative applications. Yes, we can replace some of the things that color balancing filters did with digital tools such as adjustable white balance but nothing can replace the effects of a polarizer or neutral density filter or the protection provided to the front lens element by a skylight filter.

Memory…Don’t even consider a camera without removable memory. Right now there are Compact Flash, Smart Media, xD-Picture, Multimedia , Secure Digital, and the Sony Memory Stick. They all get the job done but they are not interchangeable and Compact Flash seems to enjoys a slight advantage in number of cameras using that type and price/capacity. Of these, Compact Flash, Smart Media and the xD-Memory cards were developed specifically for digital cameras and only those cameras which can accept Compact Flash Type II can use the IBM Microdrive. On the subject of Compact Flash, there are two types but one is not a replacement for the other. "Type II" is a millimeter or two thicker than "Type I" and most new cameras accepting Compact Flash will handle both.

Personally, I prefer Compact Flash but would be hard pressed to objectively justify my choice to most people. Smart Media would be my second choice but the introduction of the new xD-Picture card could means that the development of new cameras using the old smart media cards will be limited. Of course, if you are buying your first digital camera and don’t have a lot of money invested in cards this really is not an important consideration.

There is one certainty. What ever you get with the camera will not be enough so be prepared to buy more.

Another factor directly related to memory is the file format used for storage. Common formats are Raw, Tiff, and JPEG. The "Raw’ format records exactly what your camera’s sensor captures without any in-camera processing. Each manufacturer seems to use a proprietary Raw format and you can access the information only if you use their software. Not for beginners. JPEG is a lossy compression format that provides much smaller files. The advantage is that you can get many more pictures on your memory card because of the smaller size. The disadvantage is that discarded information that the program designers considered unimportant. The information is gone for good and can’t be recovered. TIFF is probably the best solution for your most critical pictures. It is lossless but the file size is larger and fewer will fit on your memory card. I have recently noticed that many of the new "Point and Shoot" cameras are providing only the JPEG format.

Exposure Control…

Cameras today range from the simplest fully automatic "Point and Shoot" which do everything automatically and offer very little or no user adjustments to cameras which provide controls which allow complete user control of the picture taking process. Most (probably all) of the latter provide a shooting mode that allows the camera to function as a fully automatic "Point and Shoot" device when this is what you want. Let’s look at some of the different functions that are offered.

Most fully automatic "Point and Shoot" cameras provide very limited adjustability. They operate in a programmed mode in which the camera selects the aperture and shutter speed. If the camera offers different modes these can be used to exercise some control over aperture and shutter speed. For example, a "landscape" mode should provide a bias for a smaller aperture (greater depth of field) at the expense of a slower shutter speed while a "sports mode" might be biased for a higher shutter speed at the expensed of a larger aperture (less depth of field).

More advanced cameras will provide an "Aperture Preferred" mode which allows the user to select an aperture and the camera will automatically select the appropriate shutter speed, "Shutter Preferred" mode which allows the user to select the shutter speed and the camera will automatically select the appropriate aperture, and "Manual" which allows the user to set both the shutter speed and aperture. These can be very useful features and require only the most basic knowledge of photographic technique to use creatively.

One very important consideration. More and more cameras are using simple and very easy to operate and understand knobs to control basic functions. For example, if you want to select the aperture preferred mode you just twist the knob until the "A" lines up with the index mark. Other cameras use a series of nested menus to control everything. I have one of these "menu controlled" cameras and I can assure anyone who will listen that I will never buy another.

Size…Size is a very personal thing. Small is convenient and cute but they usually provide fewer features and cost a bit more. Just be sure that it isn’t too small. I looked at one the other day that was so tiny that I wondered how I could hold it and keep my fingers out of the picture. The view finder and battery capacity are other areas that sometimes suffer when size becomes the dominant feature.

Viewing System…An optical view finder is absolutely essential. I would not even consider a camera which relies totally on the LCD panel on the back of the camera. Some cameras use an internal LCD screen to imitate a Single Lens Reflex camera. This is usually a pretty low resolution display but some cameras using this method provide acceptable viewing. Just understand what you are dealing with and "try before you buy". If the store doesn’t have a powered version you can look through go somewhere else.

Battery Power…The most common power systems are those using AA size regular batteries and those using dedicated rechargeable Lithium Ion batteries with unique form factors. This means that the battery from Camera A is not interchangeable with the one in Camera B. Some cameras also use non-rechargeable lithium batteries. These can get very expensive in a hurry. For example, two Duracell Ultra 123 lithium batteries go for about $10 or $11 at Wal-Mart. These are small batteries just a little larger in diameter than AA cells but only half as long.

The AA size cells are available as rechargeable Nickel-Metal Hydride cells and are better than other chemistry such as Nickel Cadmium. The capacity of a cell is stated as a number such as "1800 MilliAmpere Hours usually abbreviated as MAH. This is a measure of how much juice the battery can deliver and the higher the number the better. Currently the better ones seem to rated at somewhere around 1800 to 2200 MAH. Higher is better. Some rechargers also provide an adapter which allows recharging from the cigarette lighter socket in a car. Very handy sometimes.

I have always recommended purchasing a camera that used rechargeable AA cells in the past. Times have changed. I now have a camera that uses a unique Lithium Ion battery and I love it. My two batteries (one came with the camera and one I purchased as an accessory) are all that I will ever need because of their power capacity. The extra battery was expensive ($45 or $50) but probably no more expensive than a charger for AA cells and the several sets of rechargeable AA size batteries that I would need to provide the same capacity.

Considering the above, I would consider a camera using either AA size cells or proprietary Lithium Ion batteries acceptable. In any event, budget for an additional Lithium Ion battery or a recharger and additional rechargeable AA cells. You will need them.

The following web page contains a comparison of battery life for selected cameras. It is certainly not all inconclusive but it is interesting. Scroll down the page until you find the battery life comparison. http://www.dpreview.com/reviews/pentaxoptio550/page9.asp

Other features…Other features that are desirable are discussed in no particular order.

A Remote Release is a very worthwhile feature. These can vary from elaborate electronic releases to a simple and very inexpensive cable release. These are useful when you have your camera mounted on a tripod and want to avoid any camera shake which will degrade the picture. An alternative is to use the "self timer" to release the shutter but I would consider this an emergency solution and not something to rely on routinely.

A detachable lens hood. If your camera accepts one buy it and use it. Their intended function is to shield your lens from extraneous light which can degrade image quality but they also provide physical protection for the lens. Last year I dropped a camera from waist level onto an asphalt hiking trail on my way to Laurel Falls in the Smokeys. The lens hood was dented but the lens was unmarked and unharmed. If given a choice of damaging a $15 or $20 lens hood or a $300 or $400 dollar lens I’ll sacrifice the lens hood every time.

A good sturdy tripod. Absolutely essential for some types of photography. Make a selection between strength and weight. I have a Bogen/Manfrotto tripod that is strong enough to support a tank. Unfortunately I don’t use it as much as I should because it is quite heavy and my needs would have been better served by one that was a little less sturdy but easier to carry. A Monopod is another very useful device that I use a lot. A monopod is just a tripod with one leg. They are not a substitute for a tripod but are very useful because they do provide a degree of support, are far easier to use, and can be used in some places that do not permit tripods. Also consider a "quick release" device for mounting your camera. I have two types. One is less than worthless and the other is worth its weight in gold. So select carefully. Be sure that it is strong, easy to attach and securely holds your camera.

Two very popular tripods are Bogen/Manfrotto and Gitzo. The first are manufactured by the Italian company Manfrotto and marketed by Bogen Photo in the U.S. Both are very good but Manfrotto are usually a bit less expensive and incorporate a feature or two that I like. Remember, the purpose of a tripod is to support your camera and Gitzo is a French company. Do we really want to rely on the French for support? Both companies manufacture a full line of tripods in both metal and carbon fiber. Carbon fiber is great but seems to cost 2 to 4 times more than a metal tripod with the same features. That’s why I have metal.

A sturdy tripod won’t do you much good unless you have a way to attach it to your camera. Some cameras are now using a plastic tripod socket. Metal is much better.

External Flash. Don’t expect too much from the built-in flash. They are better than nothing but such a small flash located that close to the optical axis of the lens won’t provide much light and will encourage red eye. If flash is an important consideration look for a camera with a hot shoe accepting an external flash. If you aren’t familiar with the term "hot shoe" it is just a place to mount a flash which includes a built in electrical connection for the flash unit.

Where to Buy…First of all, no reputable manufacturer is selling "seconds". The real difference is in service and support. A full service camera store will provide more help and after the sale assistance at little or no increase in price. That said, there are companies selling "gray market" cameras. These are cameras that were not imported by the official manufacturer’s representative and in many cases the warranty is an international one and may not be honored by the U.S. importer. For example, many mail/internet sellers sell gray market, directly imported, cameras at a lower price. Nikon U.S. (for one) does not honor the warranty on these cameras and any warranty is provided by the seller. Just be sure the camera you buy includes the official importer’s U.S. warranty. Some seller’s sell both types but the better ones like B and H Photo in New York make it very clear what you are buying. If buying by mail or over the internet it might be wise to avoid the lowest price. There is usually a very good reason for the low price. Almost all of the camera stuff I have bought in the last few years have been from Murphy’s Camera on Winchester Road or B and H Photo over the internet. I consider both to be absolutely reliable. Don’t take this as a CKCS endorsement of these sellers. I’m sure there are other equally reliable sources but these are the only two I have personal experience with. Ask a friend about their experiences with sellers. Most will be happy to share their knowledge.

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