By artificially darkening the corners and edges of images we can direct the viewer’s eye toward the center. The trick is to not overdo it, but to have it be subtle. If you look at an image and think, ‘Oh, darkened corners,’ you’ve most likely gone too far. There are several points along the way where you can employ this trick, but my preference is in Photoshop, after the image has been cropped and the contrast adjusted.

My personal method involved the Quickmask tool and an Adjustment layer. On you image, enter Quickmask mode (Q key command) and select a round paint brush of appropriate size. Then simply mask the majority of the image. Remember this is a mask, not a selection, so the areas you paint will not be affected by the next step.

After you’ve masked the appropriate areas, exit Quickmask mode (Q key command again.) The areas you haven’t masked will now be selected. Add a Curves adjustment layer (Layer, New Adjustment Layer, Curves) and bring the mid-tones down to the appropriate point. I usually use 10% as a good starting point. This is the area where you can go too far if you’re not careful, so take your time.

The great thing about doing this on an adjustment layer as opposed to directly on the image is the ability to edit the curve as well as the layer mask after the fact.

Sometimes we simply have to go with the situation presented to us. Those situations don’t always allow for full control at the time we shoot. But using a number of little techniques and gimmicks can really help a shot pull through.

I got some questions over the weekend about the details of the  1/f rule and I thought I’d share some of my answers with you. It is a simple formula which allows photographers to roughly estimate how fast a shutter speed they’ll need to prevent camera motion from blurring an image.

The “1/f rule”  simply says that the longest shutter speed you can handhold a 35mm camera, with careful technique but without a tripod or other support, without getting blur from camera motion is about one second divided by the focal length of the lens (in millimeters). For a 100mm lens, the rule suggests that you’d have a shot at getting a sharp handheld shot at 1/100 of a second (or a 1/1000), but not a 1/10, or 1/50. This is fairly intuitive. Telephoto lenses magnify more, magnify motion more, than wide-angle lenses, and so you need a proportionally faster shutter speed to get a sharp image with the longer lens.

The rule is not  particularly  precise, though, and it is helpful to keep a few caveats in mind.  

The most important caveat is that photographers vary widely in their ability to consistently hold a camera steady, varying by at least a few stops. The only way to get a real sense of how well you can handhold is to take, under controlled conditions, a shot from a tripod (using good technique), and then take a a series of several shots at each shutter speed near the 1/f rule and critically compare the results. As a result, if you’re going to photograph handheld a bit, you should go do this experiment, yourself. (I have, I figure I’m a little worse at handholding than this rule would imply.)

The density (or “pitch”) of your image sensor is a factor. The smaller the sensor pixels, the more your camera will be able to notice small motions because of movement. If you can consistently handhold a 6MP full-frame camera at 1/100 and 100mm, you’ll need a whole additional stop (1/200 of a second) to keep it sharp on a 24MP camera. Because the real issue here is the size of the pixels themselves, an 8MP camera with a cropped sensor will need (more or less proportionately) faster shutter speeds than an 8MP camera with a full-frame sensor using the same lens. In other words, it may be easier (if you are comparing cameras with the same number of megapixels, but different-sized sensors) to think in terms of “effective focal length”, multiplying the focal length of the lens by the crop factor. Because digital cameras have much smaller pixel pitches than they used to, sharp handholding  is harder than it used to be. Because our cameras can resolve more detail they can also resolve more motion, we’ve gotten pickier about “sharp.”

Finally, the approximations to the lens equation that make this rule of thumb pretty darn good for most shots break down for wide-angle lenses and for macro shots–in both cases, making those types of shots a little harder than they might otherwise be. Think of it as a one-third stop penalty for very wide shots (17-24mm), and as much as a full-stop penalty for 1:1 macro shots.

Finally, image stabilization (also known as vibration reduction) can provide as much as a couple stops worth of assistance. These technologies are wonderful and I do recommend them, but in my experience the claims for how much they help can be just a little bit optimistic.

While this will seem like a lot to digest, with a little practice the  1/f rule  becomes second-nature and a valuable tool for handheld work.

One of the primary reasons we use tripods is stability. It is simply impossible to hold a camera steady enough for a critically sharp image as shutter speeds get longer and longer, and longer shutter speeds are often an inevitable requirement of smaller apertures and wider depth-of-field.

For maximum stability when shooting from a tripod, first set up your tripod in a position where the legs have a firm connection to the ground. This can be a challenge in wet sand or snow, in those conditions, if you can sink the tripod legs and reach solid ground do so. Make sure that the leg locks (particularly on the Gitzo-type leg locks) that the legs are solid, with a number of leg locks it’s surprisingly easy to leave one a little loose, which can lead to unpleasant surprises, I’ve made this costly mistake twice over the years. Make sure the tripod head is over the center of the legs. On level ground this is simple, you simply extend the legs evenly, but in steep slopes it can be easy to set up a tripod in a way that seems stable but is actually very close to tipping over. After setting up your tripod (and perhaps before putting your camera on it), simply push the tripod to make sure it’s stable. Make sure your tripod head is locked securely as well, and make sure that you haven’t extended your center column at all unless it’s absolutely required.

While I usually recommend not touching the camera or tripod while shooting, there is an exception. High winds often leave me in a position of shooting in conditions in which you’ll still feel the tripod “ringing” with movement. Pushing the the tripod down into the ground with your hand can reduce this vibration and increase stability.

In order to avoid touching the camera, you’ll want to use a remote or a cable release, as well as using the mirror lockup feature on your camera. In digital (and film) SLRs the internal mirror flips out of the way before shooting, but the motion of the mirror creates a vibration in the camera that’s most noticable in moderate shutter speeds (1 second down to maybe 1/50 second). With mirror lockup, you press the shutter release twice, the first press locks up the mirror, the second press triggers the shutter, allowing the vibration caused by the mirror to settle out before shooting.

Take a moment (if you have that moment) to look at what you’re about to shoot. Look at your composition for distracting elements near the edges, perhaps a small change in camera posiiton will leave you with a stronger result. Take time to choose the right focusing distance for your composition, you may want to estimate the hyperfocal distance if you’re trying to for maximum DOF. Now shoot!

After shooting, don’t (save for the most pressing changing conditions) immediately run to the next shot, take a very short moment to check your exposure using your camera’s histogram function. If you’ve blown out highlights you or have otherwised missed getting a good exposure it’ll usually be easty to quickly dial in an exposure compensation adjustment and reshoot.

With care and a few good habits, a tripod will raise your photography to a new level–now, go out and shoot!