Camera shake is the bane of everyone who takes pictures more or less seriously, and especially for photographers who specialize in outdoor and macro work.  It's not that you don't know how to prevent camera shake-a tripod's the usual answer-but that applying that knowledge in the real world is a tad challenging.  Anyone who's used an SLR or DSLR for any amount of time has probably accumulated a bunch of lenses and other accessories, and carrying all the junk around makes you feel like a trekker on an Everest climb.  Add a big clunky tripod and you can go way over the top, not to mention tripping yourself and all your companions up with the extended legs.

A good option to start with is to get either a camera with image stabilization or lenses with image stabilization (Nikon calls them VR lenses).  This is important for digital photography on any lens more than about 100mm (which becomes 150 mm on most digital cameras), but if you shoot in low light you may want to try VR even for shorter focal lengths.  With VR, as we'll see, there are situations where not only is a clunky tripod unnecessary, it's actually a bad move!

There are really three decisions involved in choosing a camera platform that will strike a reasonable balance between convenience (and nothing is more convenient than no platform at all) and stability (a good studio tripod that weighs 25 pounds is nice and stable).  They are:

1. Style.  There are big and little tripods, tripods and monopods, and even camera supports that are neither, and all have different benefits.
2. Head.  You need a tripod head to hold the camera, but there's more than one kind (of course).
3. Material.  Carbon fiber is the lightest and strongest material, but also the most expensive.

Let's start at the beginning.  You have to ask yourself a simple question; "Will I have time and space to set up any tripod at all?"  If the answer is "No", then you either have to shoot hand-held or use a monopod.  Monopods are also useful for people who are so limited in the weight or bulk they can carry that a conventional tripod is out of the question.  They also work for quick setup in a limited space, which anyone who's used a tripod would realize isn't an attribute of tripods in general.  Finally, monopods work with VR lenses, and most camera companies will tell you not to mount VR lenses on tripods (or not to use VR if you do, which kind of defeats the purpose of paying for it in the first place).

A monopod is essentially a tripod leg with a space to mount the camera on top.  You can extend it like a tripod leg, but since it's a single leg (with an exception we'll talk about) it won't hold the camera free-standing, and it won't be as stable as a real tripod would be.  Everybody has different "shake internals" so it's hard to offer a rule of thumb here, but my own experience is that if you assume that the limit of safe handholding in terms of shutter speed is about 1.5 times focal length (for a digital like the D2X, or 1.0 times focal length for a 35mm or a digital with a CCD as big as a 35mm film image), then the safe limit on a monopod is about a quarter of that (four-tenths focal length).

When selecting a monopod, it's absolutely critical to get one that's reasonably tall-that will let you shoot at roughly eye level.  Bending over to use the monopod will almost certainly make you more unstable.  In fact, the most stable monopod stance for most people is to stand facing the subject, legs (your own) slightly spread, with the monopod squarely between your legs and about even with your heels.  You're then "pulling back" a little on the monopod, which helps to stabilize it.  Obviously the monopod has to be pretty tall to make this work, or you'll be bent like a contortionist.

Monopods won't work for beans if you have to shoot long exposures (a tenth of a second or longer, in most cases, though they'll work better than trying to hand-hold at those speeds and may work if you have VR), and since they won't self-stand, you can't leave a long telephoto attached while you change to a zoom for a different kind of shot.  For situations where you need stability or free standing capability, you need a tripod or something else that will hold the camera and not just stabilize it.

There are three kinds of tripods; inexpensive heavy stable ones, expensive light stable ones, and unstable ones.  The key thing to remember about tripods is that, like monopods, you probably don't want to be bent double to use them.  That means the tripod has to stand tall, which means that either it has to be made of very light strong material like carbon fiber (expensive), of thick tubing of something heavier like aluminum, or of something thin and jittery.

To size a tripod, measure your height to eye level and subtract the height of your tripod head (assume about 3 inches if you aren't sure) and the distance between the camera bottom and the viewfinder (assume about 2 inches if it's too much trouble to measure).  The result is how high your tripod should extend without cranking up any center post.  Center post extensions are OK for light camera/lens combinations, but if you stick a big telephoto on one, you'll get shake.

If you're much more than about five and a half feet tall, you'll probably need a three-section tripod, meaning that the legs consist of three concentric tubes that collapse into each other.  Four-section tripods fold up smaller, but they get whippy if they're too high so most manufacturers make them shorter.  I think that if you really plan to carry the tripod around in the wild, you need carbon fiber.  It will cost about double the aluminum models, but the weight advantage will be considerable.  For indoor studio use, get a big aluminum beast and forget it!

Now for the tripod head.  There are three kinds of heads widely used, pan, ball, and gimbal:

• The pan head has one or two levers sticking out that let you loosen or tighten the head to hold it into place.  Usually, you can unlock the pan dimension separately, so you end up with a "tilt-and-pan" kind of motion.  This kind of tripod is often used with video cameras because it lets you move the camera laterally as needed and it's pretty easy to set up and use.
• A ball head is just what it sounds like; a metal ball-and-socket joint with something to clamp the joint down when you get it adjusted.  Ball heads are small, more adjustable, but harder for most people to get into position.  They can tend to flop around a lot.  There are advocates of both.  Take your choice, but it might be a good idea to watch users of each type to get an idea of what would be ideal for your own style.
• The gimbal head is made for long telephoto lenses (400mm and up).  This head looks like a kind of "C" with the bottom attached to a tripod in the usual way and the top holding a clamp to which the lens is attached.  Most of these gadgets have a lens clamp that's rotated 90 degrees from the usual orientation, and this type will generally only work if you have a rotating ring on the lens.  The gimbal head will let you move the lens like a fork mount in a telescope, and it will lock in any position.  If you're going to do a lot of telephoto shooting from your tripod, get this kind of mount.

You probably won't need a head on the monopod you get as long as you can fit it with a quick release adapter.  You'll also need a quick release plate for the camera and/or lens, and an adapter for the head.  Most tripod heads will be compatible with the Swiss Arca style quick-release, and it's easy to get the plates for this style to match both lenses and cameras.  For long (over 140mm) lenses, you'll want to mount the plate on the lens rather than on the camera to keep the rig from being unbalanced.  Be sure your lenses have the rotating collar for a tripod mount, of course.

My own choices in this space have been hard-a-coming, so to speak.  I've owned about four tripods, so I've obviously thrown three of them away.  My current tripod (and, I hope, my last) is a Gitzo 1227 carbon fiber tripod.  I've added the Acratech ball head, which is more than capable of holding up a digital camera with a reasonable zoom lens.  I have a Kirk King Cobra gimbal head for my D2X and the Sigma 500mm telephoto.  I've used this combination on three major outdoor trips (Yellowstone in the winter, Churchill in the winter, and coastal British Columbia in the spring), and I like the result.  On a recent Yellowstone trip, I got serviceable shots of a bear feeding on a bison with the ASA on the D2X cranked all the way up and still getting only a 1/100th shutter speed with a 500mm lens! Gimbal heads work!

In the monopod area I have two options.  First, I have a Bogen 682B monopod, on which I keep the Acra ballhead.  This guy has little detachable legs that add to stability but don't contribute much weight.  They won't safely support the camera if free-standing, though.  My hope is that the monopod will serve in applications where there'd be no time to set up a tripod or where the space to do that would be hard to come by.  I've been field testing the Bogen and so far I love it.  It's especially good for shooting where you can't set up a tripod quickly or at all.  I did a trip to Churchill in November 2003 and for some incredibly dumb reason decided I didn't need both monopod and tripod, so I took the latter.  I'd have been better off with the monopod.  On a tundra buggy, you can set a tripod up on the back deck but you'll annoy the dickens out of everyone traveling with you, and if it's too cold or windy (it was -4F and 50 mph winds at one point) you can't go outside at all.  For shooting out of a vehicle, a monopod is great.] I've made the "no-monopod" decision a couple of times more in later trips (apparently never destined to learn my lesson) and each time I've regretted it. I'm going to try to learn discipline now!

The problem with the Bogen is that it's still kind of heavy, so I added a Gitzo 1566 monopod, which folds down really small (about 18 inches) and is much lighter.  This is what I tend to use where I have to hike around.  With this, and the Bogen too, you can attach the camera (being sure it's tight in the quick release mount!) and put the thing over your shoulder while walking.

As I moved to the D2X (with 2x crop mode) and got the Nikon 80-400 VR, I've stopped taking the 500 mm on trips except where I have a vehicle to haul things.  I've also stopped using a tripod, and have been finding myself increasingly relying on the Gitzo monopod and VR.  That works most of the time, but there are still times when you'll risk whacking your companions.

Which brings us to some other camera platform options:

   1. Table-top tripods.  These are little portable guys you can sling into a pack or pocket to provide emergency support.  If you're shooting a lens of relatively short focal length, they may save a couple of shots if you have some place you can set them up on, but unless you like crawling on your belly they demand some higher object to rest on.  They will also tip over frontward if you put on a long lens.  If you have a little instamatic-type camera or a small digital camera, you might find these OK for things like setting up on a picnic table for self-portraits.  In general…forget them.
   2. Clamp-pods.  These are tripod heads with a clamp attachment, letting you latch the thing onto a tree, pipe, etc., or mount it in a car window.  I think a small clamp head is a better idea than a table-top tripod, and if you're taking a photo-trip by car (or in that Churchill tundra buggy) it might be nice to have the window mount.  It's just a question of personal style.  There are no general comments I can make about how stable these would be; it depends on how stable the clamp is, how the camera itself is mounted, and how stable the thing you're clamping it to might be.  If you take a lot of pictures out of a car, or if you normally have time to clamp something to a nearby object, you may want to check this idea out.  Remember, though, that you can damage things with the clamp so be very careful.
   3. "Gunstock" tripods.  These are shoulder rigs that let you hold the camera like a gun to shoot a picture.  I've tried these a couple of times and didn't like them, and I'm also nervous about carrying something that looks like a gunstock through airport security.  My personal opinion-pass.
   4. Beanbags. This is essentially a soft-ish pad filled with something granular (often actual beans) that can be used to steady a camera, providing you have something to rest it on. The problem with beanbags is that it's frequently not all that easy to find such a stable resting place. Imagine yourself in a safari jeep, with the bag resting on the window. You shift your camera, and boom...some African animal has beans for dinner and you lose your camera support.

I acquired a beanbag and I liked the result, but unfortunately I ended up losing the thing while on a trip.  The big advantage for one is on a cruise, where you can use the beanbag to steady the camera on a rail or flat surface to shoot.  If I can't find the darn thing I'll buy another!

If it's at all possible, you should have a tripod or monopod with you for every photo shoot, and on any complicated shoot you take both.  There is no picture that will not benefit from the additional stability they'll give you.  At the very least, even a monopod is good for two to three f-stops, which means better depth of field if you need it.  It can also let you shoot at lower ASA, which means less digital noise.  I know they're a pain to carry, and I know there's no way to look cool or fashionable with a bunch of photo gear hanging off you, but hey, you'll probably never see any of the other people you meet on photo trips again and you'll be stuck with the pictures you take forever. I have carried a monopod on some hikes in the arctic that were tough enough to negotiate with no gear at all, and I got shots that made the effort worthwhile.

Easy choice.  Get used to the extra load a tripod or monopod represents!