The Autofocus Lock (AF Lock) is possibly one of the most useful additions to camera technology since, well, autofocus.  AF Lock allows you to focus on a subject and then reposition your camera in order to reframe the shot.  The use of Auto Focus Lock is fairly simple.  As always, you would center your subject within the focus area and press your shutter button half-way.  Autofocus will then determine an appropriate focus.  On most cameras, you then press-and-hold the AF Lock button and reposition your camera.

This is especially beneficial to those with consumer-level cameras that have fewer autofocus zones.  While higher-end cameras may provide more focus zones, the use of AF Lock will basically take the focus zone count out of your criteria when choosing a camera.

Why is it that everyone spends so much time and effort evaluating a SLR/DSLR camera when the lens is far more important. Don’t believe me? Then why is it that the best lenses available easily cost more than most of the SLR cameras on the market.

Let me ask the question a different way.  If a professional photographer had to give up either his lenses or his camera, which do you think he would choose?  He will choose to give up his camera.  Why?  Because any camera that will fit his lenses will still allow him to make beautiful shots.  But the kit lens will be limiting no matter what camera its mounted to.

So again I jump on my box and state what I often have stated: When you are buying a camera, you are buying into a system. So when you are considering a camera, consider all of the lenses available for that camera as well.  The interface and feel of one camera means nothing if you dont’ like the lenses available.  And once you drop a few thousand dollars on lenses for your camera, you likely aren’t going to switch brands.  So do your homework.

Tripods come in all sizes, and price ranges.  The expensive ones are definately worthwhile and as soon as you can justify the expense, they’re well worth the price tag.  But if you’re like me, you’d rather spend what little cash is available for your hobby on things like lenses and filters.  I truly believe it’s essential for every photographer to own a tripod, but it doesn’t need to cost you an arm and a leg.  Here’s a list of essential features that your tripod should have:

1. Strength - If the tripod can’t hold your equipment, it’s worthless.  It needs to be able to support all the weight of your gear and then-some.  The stronger your tripod is, the less it will be influenced by other forces.  Most of the time, this is the main reason for cost differences.
2. Control - You should be able to easily use your tripod’s head.  Most of the more inexpensive tripods include a Tilt/Pan head.  Ball heads are more expensive because of their larger range of motion but may be more difficult to use.  Get whatever you are comfortable with.  Note that when you can afford a more expensive tripod, the heads are often purchased separately.
3. Quick Release Plate - Many tripods, even cheaper ones, have a quick release feature where a plate is mounted to your camera and it snaps into the tripod with a lever.  This is very convenient, especially for landscape photographers who move their tripods regularly.
4. Quick Release Legs - Cheaper tripods will utilize some sort of screw mechanism for the legs.  This is slow and not often dependable.  Look for quick release levers or quarter-turn leg locks.  They’re well worth the price.
5. Gear Hooks - Yes, you can hang your gear on it, and I guess that’s convenient.  But the real reason you want a gear hook is stability.  If your tripod can handle all the weight, hang all your gear on that hook.  The weight makes the tripod more stable.

One last bit of advice:  The cost of a tripod may be somewhat intimidating.  You can literally spend hundreds of dollars on a tripod.  While that pill may be hard to swallow, keep in mind the value of the equipment it is supporting.  A $900 camera body (and that’s not even a professional camera)  with a $650 lens deserves a tripod worth a couple hundred dollars.

When taking long exposures (or even sometimes, mid-range exposures), you need to reduce the camera shake as much as possible.  A tripod helps, but knowing what can cause camera shake is beneficial to isolating, and addressing, a problem.  Here’s a short list of things that can cause your camera to shake, in no particular order.

1. Unsteady Hands - if you are not blessed with a steady hand, you may need to use a tripod much more often.
2. An undersized tripod - make sure your tripod can support the weight of your camera AND your lens and all other peripherals).
3. Mirror Shake - the mirror in your SLR camera slaps upward just before the shutter opens.  On long exposures, this won’t be noticeable.  But on the medium length exposures, it may be beneficial to utilize your camera’s “mirror lock-up” function.
4. Wind - Strong winds will move your camera just enough to blur your photo.  Shield the camera as much as possible, or try lowering the tripod or spreading it’s legs.
5. Bad Tripod Placement - Be very attentive to where you set up your tripod.  A wooden deck, for example, can potentially cause camera shake if people are moving around on it.  Soggy soils may heave if your weigh shifts nearby.  Consider a different location.
6. Pressing the Shutter Button - Any rifle instructor will tell you to “squeeze the trigger, not pull”.  Same goes for cameras.  Better yet, use a remote trigger and keep your hands away from the camera.
7. Sound - Yes, sound.  Sound, especially low frequency sound, compresses air.  It can shake everything near it, including your camera.  So if you plan on photographing in dimly lit conditions, such as at a dance club, you’ll want to invest in a remote flash and a diffuser so that you can get the shutter speed as high as possible.

This is, by no means, a complete list, but a good primer to help you become more aware of your environment when setting up for a photo shoot.  Feel free to add your own observations by leaving a comment below. 

Sometimes, you want to take a photo of something, but the lighting is poor and you’re without a good tripod. Say, for example, your tripod is in the car, and you would miss an opportunity if you left to grab it. If your camera is small enough, you can prop it on almost anything and set a timer and you’re set. A tripod would be ideal, of course, but there’s no reason to miss a shot because you don’t have your tripod with you. Use whatever is available. I’ve used plates, books, shot glasses, my camera bag, and the list goes on. If you have a heavy lens on the front of your camera, you will need a spacer of some sort. Use your lens cap or a filter case as a spacer.

Again, the idea is not to replace the tripod. But in a pinch, there’s always something you can use.