DigiCam 101

(A Megapixel is not a Huge Pixel!!!)

By Lou Pastura

OK, our erstwhile Macintosh editor has convinced me that there's enough interest in this subject to warrant an article or two. I guess your response will determine whether he's correct...and whether I'm the right person to do the writing. What I hope to do in a few pages is give you an overview of the issues to consider as you contemplate moving from the world of traditional film photography and processing to digital imaging. Please bear in mind that I am only lightly touching on issues about which entire books have been written. At the end I'll point you to some Web resources for more detail from real experts.

Why digital?

Improved Results: Right off the bat, I will personally guarantee that going digital will make you a better photographer. Pretty strong opening statement, huh? Think about it this way: one of the big differences between a run-of-the-mill snap shooter and a "pro" is the latter's willingness to expose multiple rolls of film to achieve the best possible image. With a digital camera, the playing field is leveled. You can take multiple images of a subject (with no expense for film, processing or printing) and decide later which one looks the best. My office wall is the repository for a number of prints that cause visitors to suggest that I'm a "great" photographer. I ordinarily don't go out of my way to explain that the four photos on the wall were painstakingly chosen from a cache of several hundred. When you take that many, some of them have to be good! With care and practice your knowledge and skills will improve, as will your batting average (that's the true difference between an amateur and a pro), but in the meantime, you can obtain outstanding results with the law of averages as your photographer's assistant.

Immediate Feedback: This benefit of "going digital" is twofold. The first relates to the previous item. When you take a picture, you can immediately review the results, erase it if you don't like it, and shoot again, as needed. The other feedback is for your subjects. Imagine the reaction of a group of children gathered around you to look at a picture of them that you've just taken, and that immediately appears on your camera's LCD screen. And that reaction is not limited to children...adults are not immune. (Adults, however, will complain more about how they look and want you to re-shoot the photo!)

More Fun: Take the reaction discussed in the previous paragraph and add the ability to easily and quickly put your images to use in a wide variety of ways:

• Email pictures of the kids to the grandparents
• Personalized greeting cards and postcards
• Personalized T-Shirts
• Novelties, e.g., cups, key chains, etc.

More Uses: Your only limit is your imagination. For example, I was having a problem with my gas fireplace. I tried to describe the mechanism to the customer service staff at the store with little success, and they needed to know the exact type of unit installed in order to resolve my problem. Of course the manuals and paperwork were safely filed away...so safely that I had no earthly idea where to find them. I took a picture of the mechanism, printed it and returned to the store. Problem solved. And remember: an image doesn't have to be printed to be useful. A photographic inventory of a valuable collection or of jewelry or household goods (an inventory for insurance?) can be easily and inexpensively stored on compact disc and archived in a safe place like a safety deposit box. And updating is also easy, fast and inexpensive.

OK, digital it is...now what?

So now it's time to buy a camera. There are the traditional issues of point and shoot versus SLR (Single Lens Reflex) camera bodies, lens quality and speed and the camera's light sensitivity and size, weight and ergonomics. But there are also a whole slew of new things to consider such as resolution, internal storage (memory), image transfer, power options, viewfinder versatility, speed, focal length flexibility and archival storage. Let's review the traditional issues first and then move on to new issues raised in the digital world.

Point and Shoot Versus SLR: This one is easy. If you're currently using a point and shoot camera and you're happy with it, you'll likely be just as happy with a point and shoot digital. If, on the other hand, you prefer Single Lens Reflex with lots of buttons, option and controls, be prepared to spend more for the privilege. Note that higher end (and higher resolution) point and shoot cameras will have a large subset of the features of the SLRs.

Lens/Glass: Just as your Mac's monitor is critical because it's the key interface between you and your machine, the lens is the part of the camera most critical to your success. All the gee-whiz camera features in the world will not help a picture that starts out unclear or distorted because of problems with the glass. This is not to say that some problems can't be corrected in the virtual darkroom of your computer, but this can be both frustrating and time consuming, and the correction is almost never as good as a well-shot original. Further, the result of any editing you do in the computer to either correct or enhance your image will be improved by a higher quality original. Look for the highest quality lens available in your price range. Glass is always better than plastic...but take care: all glass is not created equal. If in doubt, stick with major camera manufacturers like Olympus or Nikon. Lens speed (the lower f-stop number the better) and optical zoom (higher is better) capabilities are also important considerations that I'll discuss in more detail below.

Disclaimer: For digital photography, I am an unabashed Olympus fan and my bias will show throughout everything I write on this topic, so be prepared! [Disclaimer #2: the Mac editor is a Nikon and Olympus fan, too, so you are mostly forgiven.]

ISO, Lens Aperture (f-stop) and Shutter Speed: These three specifications combine to determine how light sensitive your camera will be. This, in turn, translates into how well it will perform in low and bright light, how much you will be able to control depth of field (the amount of the image that appears in perfect focus), and how much you will be able to minimize image problems due to camera movement. ISO is a measure of the light sensitivity of your camera's image capture medium (film in a traditional camera, a charge coupled device in the digital arena). A higher number indicates more sensitivity. More sensitivity means you can shoot with the lens closed down to a smaller opening, increasing depth of field, or you can shoot with a faster shutter speed, which will help "freeze" motion and reduce or eliminate problems due to camera shake. Higher ISO settings can, however, introduce noise on some cameras. In film cameras this appears as graininess in the pictures. Digital images will exhibit pixels that are too bright, too dim or off-color. All of these can be fixed after-the-fact, but as discussed earlier, it's a pain and the results are never as good as taking a good image to begin with.

Ergonomics (All the Features in the World won't Help, if You don't Carry the Camera): Traditional camera designs have been limited by the need for two places to store film that have to be positioned so that the film moves from one to the other with the shutter opening in between. These limitations don't exist for digital cameras and designers have begun doing some interesting things. These may or may not be to your liking, so look around. From a portability standpoint, smaller and lighter is better, although you may sacrifice some features for that convenience. For some, the heavier feel of a camera shaped more like a traditional 35 millimeter SLR may have some appeal. There's also something to be said for a heavier camera being easier to hold steady...until it gets too heavy, and then the opposite is true. Bottom line: try out a number of different sizes and shapes. See what feels best to you. There are no rules here, only preferences and needs in terms of features and portability.

Resolution: Okay, this is an important item, but it's also an easy one, at least at the basic level. Resolution refers to the maximum number of individual picture elements (pixels) the camera's imager is capable of capturing. There are different levels of maximum resolution available, depending mostly on how much money you want to spend. The basic realistic choices for printed output are one, two, and three megapixels. Anything less than one megapixel is probably suitable only for display on a 72 dpi computer screen...which may be ok, if that's all you plan to do with your images. On the other end, with one exception, a high end "prosumer" offering from Olympus (remember, I said I liked them a lot?!), anything over three megapixels is going to lighten your wallet more than a brand new top of the line G3 with all the bells and whistles. Generally speaking, any camera capable of higher resolution will offer a photo by photo option to shoot at some or all of the lower ones.

Why might you want to choose a camera with lower resolution? They're less expensive or may be faster in terms of frames per second or have more features, such as an extremely long zoom lens. Why shoot at a lower resolution if higher is available in your camera? Perhaps you're out in the field and running out of storage space. Perhaps you know that the images you're capturing are going to only be used on the Web. Smaller images are quicker to upload. They're also quicker to store in memory and quicker to transfer to your computer for storage or manipulation.

Having said all that, I confess that I almost always shoot at maximum resolution. Storage is cheap and the time isn't an issue for me. If space is a problem, I prefer to use a small to moderate amount of file compression (an option in all modern digital cameras) as opposed to giving up any resolution. I almost always reduce resolution and file size in PhotoShop before uploading anything to friends or the Web. Being a less than practiced pro, I need all the pixels I can get for postproduction work (cropping and editing).

Generally speaking, one megapixel will produce an acceptable 4x6 print. Two megapixels will go to 5x7 and three will be okay at 8 x 10. I say generally speaking because I've seen more than acceptable results beyond these limits, but final quality is very dependent on the quality of the camera (remember the earlier discussion about lenses?), printer and paper. There is also software that will enable you to boost the quality of prints from lower resolution files, but beginning with a bigger file will always produce better results than software tricks. (Note: Some cameras also boost apparent resolution by way of a hardware trick called interpolation. This has been the subject of much debate, with the purists heaping scorn on those who would resort to such dishonest hardware chicanery. I say try the cameras and see what you like. I've seen some outstanding photos from 2 megapixel cameras pushed to 4 and 3 megapixel cameras pushed to 6.)

Please bear in mind that quality is a very subjective and personal thing. Prints that delight me may cause you to ask yourself "Why would he settle for that?" Unless you're going to try to do this for a living, the person you most have to please is yourself (or your spouse, but that would be the subject for a different article in a different magazine).

In Camera Storage/Memory: This is another subject that's been hotly debated in various publications and on the Web. It's also pretty simple at the basic level. There are two issues: size and format. Regarding size, more is better, but more expensive in terms of media cost. (That was easy, wasn't it?) Regarding format, there are three major competitors, with more announcing products or developments every day: Smart Media, Compact Flash (Type I and II) and Memory Stick (a proprietary format from Sony). You really can't go wrong with any of these, so I wouldn't recommend basing your decision on the type of storage your prospective camera requires. Compact Flash Type II is the way to go if you want lots of space. IBM makes tiny hard drives for this format that max out at a gigabyte. Needless to say, this is overkill for most of us. If you are interested in the micro-drive, be sure your camera supports it. It draws lots of power and some cameras can't handle it even though it physically fits. In the flash card realm, Smart Media and Memory Stick both max out at 64 megabytes, although higher capacities are coming. Compact Flash cards currently top out at 256 megabytes.

Transferring Images to Your Computer: OK, so you've taken these great pictures. Now you have to get them to your computer so you can print, edit, crop, enhance, email and so forth. When file sizes were smaller, serial transfer was sufficient. As file sizes have grown, USB connections have become more common. Make sure that whatever camera you buy is compatible with your computer, i.e., a USB camera connection won't work with a computer without USB. If your computer is a laptop with a PCMCIA slot, you're in luck. PCMCIA readers for Smart Media and Compact Flash are inexpensive and fast. My Wall Street PowerBook has 2 PCMCIA slots, each with a dedicated card so that I can just insert Smart Media or Compact Flash cards (my camera uses both) as needed. It's like having a port on your computer dedicated to your camera's storage device. There are also external USB readers that will accommodate either or both formats. The advantage to all of these external devices is that they don't require you to use precious camera battery power to do image transfers. They also don't require that the camera be tethered to the computer. Another external alternative, albeit a slow one, is an adapter for Smart Media that plugs into you computer's floppy drive (if you have one in this modern day and age). I don't recommend this for a day to day solution, but it's handy on the road because it's portable and will enable you to transfer files almost anywhere there's a computer, provided you can get permission to install the driver, which is available in both Mac and Windows 98 flavors. (I haven't seen one for Windows 2000, but I haven't looked very hard, either.)

Power (Without a Working Battery, this Thing is an Expensive Paperweight): This is another area where traditional cameras, even "electronic" ones are very different from their digital cousins. In traditional photography, you put a battery in your camera and forgot about it for months or years at a time. In digital photography, you must constantly be aware of the charge status of your batteries. Without the battery, you have no flash, no zoom, no LCD display and, worst of all, no shutter!

The good news is that, at the basic level, this is another area where good advice is simple: Rechargeable Nickel Metal Hydride (NiMH) batteries are the way to go. With regard to size and shape, go with a camera that takes AAs. Other alternatives either don't work as well or are too expensive, at least right now. I originally did the right thing for the wrong reason. I looked for a camera that would use AA rechargeables so that, in a pinch, I could use alkalines. Dumb idea. Alkalines last such a short time in this application that they're just short of useless. I got lucky in that, unbeknownst to me at the time, Olympus (remember I said how great they were) uses a battery holder in the camera I selected that will take CR3 Lithium batteries as well as AAs. The Lithium batteries are terribly expensive, but they last a long time and are worth it to carry around to use in an occasional emergency. There are also external battery packs with longer life than 4 AAs. These ordinarily clip on your belt and plug into the camera's AC adapter jack.

Which brings us AC adapters. Most new cameras will accommodate one, and if external batteries or AC power are important to you, make sure yours is on that list. An AC adapter is useful if you're going to be doing a lot of work indoors in a setting where you can afford to be tethered to a wall outlet (for example, in a controlled environment like a studio), or if you're using the camera with a cable to transfer photos to a computer. Some models will include the adapter right in the box. Others will have one available as an option. There are also third-party adapters (which is what I have) that work just fine and tend to be less expensive than branded versions. Just make sure you get one guaranteed to be compatible with your camera. Incorrect voltage or polarization can cost you a lot to repair damage that can occur in milliseconds.

Viewfinder Versatility: This is an ergonomic issue that adds potential flexibility to how you can capture images. On almost all digital cameras, the LCD screen used to review photos in the camera's storage can also be used as a viewfinder. The down side to this is that using the LCD screen for this purpose discharges batteries at a high rate. This disadvantage is offset on some cameras because the LCD is attached in such a way that you can hold the camera in some truly unique positions to take photos you would not be able to frame in a traditional viewfinder. The over-the-heads-of-the-crowd shot at a parade or concert is a good example. On most cameras you take your best guess and fire the shutter release. On a camera with a swiveling LCD you have a much better chance of framing something that will actually be usable.

Speed: Just like batteries, speed (other than shutter speed) is not an issue you ever think about in traditional photography. Digital cameras, however, have three main areas where speed, or lack thereof, can be an important consideration:

• Off to On: The time it takes to "boot" the camera can cause you to lose shots, especially if your subjects are children or animals. This is less important in posed settings or settings where you have more control over your subject.
• Shutter lag: This one takes some getting used to. In a traditional film camera, you press the shutter release and instantaneously capture the picture. All digital cameras exhibit some form of delay here that you must adjust to. If you use autofocus or autoflash, the delay can be longer depending on the camera. Some cameras have a feature that enables you to set the focus and flash by pressing the shutter release half way. This speeds the camera's response to the final press of the button. One of the reasons I picked the camera that I did was because the shutter release delay was so small as to be imperceptible. Again, if you're shooting kids or animals, a delay can cause you to lose expressions and poses at a critical moment.
• Speed in Saving to Memory: Back in the good old days of film, you could shoot as fast as you (or your motor drive) could advance the film. A digital camera needs to store each image to free up the imager for the next shot. Some cameras are just faster than others. Others use internal memory to store pictures as you shoot (faster than transferring to a flash card) enabling you to shoot a series of pictures by holding down the shutter release, similar to what you would accomplish with a motor drive on a traditional camera. The number of pictures that can be captured and stored (and how fast this all happens) depends on the speed built into the camera, the size of the image file and size of the camera's internal RAM. Ordinarily, this "burst mode" shooting will not work with flash because the flash can't cycle rapidly enough to keep up.

Focal Flexibility (or How Much Zoom is Enough?): Most new digital cameras (take care because there are exceptions) have some capacity to "zoom" the lens from a medium or wide angle setting to moderate or extreme telephoto. Most are 2-3x. Some have a telephoto range that 35mm photographers dream about, as much as 10-14x. How wide a wide angle setting and how long a telephoto setting you want or need is a matter of what you plan to shoot and your own style. Being not much of a creative photographer, I follow the rule of "Get in close, and when in doubt, get in closer." A long telephoto helps with this because you can close in without invading personal space. It's also handy for nature photography because the wild critters will be long gone if you approach too near. Some new cameras even have digital stabilization for the long lens, which helps eliminate potential problems with camera shake that otherwise could only be resolved by using an external support such as a tripod.

As you shop for a camera you will also come across something called "Digital Zoom." This combination hardware and software trick involves reducing the resolution of the picture and filling the LCD and/or viewfinder with the resultant "larger" image. Since this can be accomplished after the fact in your computer, why would such a feature be popular? The short answer, at least among the digital photographers I know, is that it isn't. It might be useful if you're trying to coax extra extension out of a lens for pictures that will only be viewed on a computer, e.g., via the web (see earlier discussion on resolution), or if you're running out of storage space and need to squeeze a few last pictures on to a crowded memory card. Beyond that, I'm stumped. If any of you can think of a good reason, send me an email.

Another option available for some cameras involves add-on lenses for wide angle, telephoto or macro work. If you're going to get into these, stay with major manufacturers of cameras and lenses. (See previous discussion on lens quality.) Olympus (there I go again) does a very nice job in this area.

Archival Storage: This is an important issue. It doesn't have an impact on your camera decision, but it is a critical issue: you have no negatives. If you lose the file, you've lost the picture forever. CD-ROM writers are becoming standard fare, and I advise you to get one if you're going to be at all serious about digital photography. Remember: it's not if your hard disk is going to crash, but when. If you're like me (and for your sake I hope you're not), backups to floppies or other media like Zip disks are just inconvenient enough that you probably won't do it thoroughly or consistently. Cataloguing and keeping track of all those pictures in a way that you can recall and view them in a useful manner is an issue better left for another article. Suffice it to say that it's something you need to think about and plan for.

Other Gadgets (What else will I need): Most of these items have been discussed elsewhere in this article, but I wanted to gather them all in a single place for your convenience and so that you clearly understand what you'll likely need or want in addition to the basic camera package. You need to look around carefully and aggressively. Some of these items may be included by the manufacturer or by a reseller looking to add value and entice you to buy without reducing the price.

• Extra Flash Memory
• Extra NiMh Batteries and Charger
• External Battery Pack
• AC Adapter
• Archival Storage
• Add-on lenses
• Tripod

Service: This is a personal choice that I'm reluctant to make a recommendation on, but it's important enough that I want to encourage you to think about it and make your own decision. A digital camera can be a big investment, and repairs can be outrageously expensive. Ordinarily, extended warranties are cheaper than a repair. A warranty that covers incidental damage is better than one that doesn't. Keep in mind that you're going to be carrying this high tech gadget around, subjecting it to potential damage or loss.

Web Sites: As I mentioned earlier, this article really only skims the surface of topics that deserve a lot more attention. I've tried to give you an idea of what to think about and some of the alternatives, but I would never suggest you should read this and then run down to your local camera store. With that in mind, I'd like to refer you to some real experts who have taken the time and trouble to make a truly incredible amount of outstanding information available via the Internet.

• www.shortcourses.com: This is an outstanding site by Dennis Curtin that offers three terrific on line references. They are "Short Courses" in 1) Digital Photography, 2) Choosing a Digital Camera, and 3) Using Your Digital Camera. The course in Choosing a camera is a hundred times better than anything I've written here; in fact it was very hard to write my own article instead of just excerpting Dennis's work. I did everything I could to convey my experience and thought process, but I recommend highly that you look at what he's put together. Simply put, if you like anything here, you're going to love what he has to say. He also publishes for sale a series of camera manuals intended to be better than what the manufacturers provide. Suffice it to say, I've purchased two of Dennis's manuals one for each of the two digital camera models we have in the house. (Before you ask, yes, they're both Olympus!)
• www.steves-digicams.com: News, reviews, cameras, accessories and references to other sites. I can't say enough good things about this site. In my opinion, it's the best overall digital photo site on the web. Spend a little time here looking around. It'll be worth it.
• lonestardigital.com: Not as extensive as Steve's site, but has a GREAT list of links to explore if you've the time and the inclination.
• www.dpcorner.com/index.shtml: This one's by Arthur Bleich, a prolific writer and true expert. Lots of instructional material and reviews.
• www.dpreview.com: By Phil Askey, another prolific expert. News, reviews and discussion forums.
• www.dcresource.com, www.imaging-resource.com, News and reviews.

These are only a few of many, many online resources. Look around. If you find a favorite, email me and I'll include it in a future article.

So there it is, best summary I could muster. If you have any questions, send me an email at lou.pastura@wap.org and I'll respond to as many as I can. If I get enough, I'll compile them into another article. Also, if there's a topic you'd like to see covered in more depth, let me know and I'll try to do that as well, although if you read the web sites I identified above, you'll soon know more than I do!

One last word of advice: Searching for the "perfect" digital camera is fun. Taking pictures is more fun. Don't get so bogged down in the search that you miss the opportunity to enjoy your camera and take some great pictures. Also (thanks to Lawrence Charters for this one, because truer words were never spoke!), just because some new camera comes out with some feature your camera doesn't have doesn't mean you have to get depressed and stop taking pictures. Forget about it! Get over it, or you'll spend more time being depressed than using your camera. All cameras are good one way or another. Don't get carried away with the decision and the specs; have fun and take some pictures.