Bringing Photographers Closer to Their Natural World
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You should use a tripod most of the times that you expose by ambient (not strobe) light. When tripod use is prohibited or impractical, try to use a monopod, or a shoulder stock. There are image stabilization lenses available for some systems that allow the photographer to handhold his camera at slower speeds, but remember, that only adds about one to two (if you are really steady) stops. The slow films used by many for landscapes, such as Fujichrome Velvia, will be hard to hold steady even with image stabilization in many lighting conditions. Why is a tripod essential? Many believe that blur due to lens movement is inevitable at any shutter speed slower than 1/1000 sec. At very best, the general rule is that you might (depending on how steady you are) be able to handhold at a speed that is the reciprocal of the focal length of the lens you are using (i.e., 1/300 second with a 300 mm lens). Most of us do think that the use of a tripod also promotes greater care in composition. The purist may even say that handholding is strictly for dead photographers: a human pulse beat will cause 200 microns (about 0.008 inch) displacement for 1/10th second. Assuming a shutter speed of 1/250th sec., this movement alone will cause a 22% loss of resolution with a system that is otherwise capable of reproducing 100 lines-per-mm (lpm). And at a shutter speed of 1/125th sec., this performance would degrade to only 53 lpm—a 47% waste of what you purchased (refer John B. Williams: Image Clarity, page 191). However, we have all seen extremely sharp images made with image stabilization lenses and at faster speeds. In the end, you must judge for yourself how steady you are and what you consider sharp enough. Can I make rapid changes of position and composition when using a tripod? Once you have become accustomed to using the tripod and head you select, you should be able to move it quickly enough to follow animals and even to pan flying birds. Luckily, landscapes don't move around very quickly. If you are uncomfortable with setting up with the tripod, you can pick your location and viewpoint, and create your basic composition with the camera off the tripod head. You can then mount the camera on top of the tripod for final composition, “fine tuning” and focus. After you become comfortable with the tripod and head, this should seldom be necessary. Different heads afford different levels of ease of movement. We suggest you talk to your friends about the heads they use and their level of satisfaction with them. We generally use Bogen 3047 pan and tilt heads, which we find easy to manipulate and very sturdy. We also use Bogen 3021/3221 tripods, which will allow you to get almost to ground level or as high as 75"+ with the head attached. The 3021/3221 is very sturdy and a medium weight, so it won't wear most of us out on the hike. The combination of the Bogen 3221 tripod and Bogen 3047 head will generally cost about $160 to $200 if purchased from New York. It's cumbersome to attach and remove a camera from my tripod's head. Is there an easier way? Use of the common “screw on” method for attaching your equipment to the tripod head is tedious, insecure, and invites needless wear. Instead, nearly everyone will use a reliable quick-release system. A quick-release system consists of two basic pieces: a quick-release clamp, and a compatible mounting plate. The clamp is attached (permanently) to your tripod head, and the plate is screwed onto the base of any camera or lens that you intend to mount on the clamp. We normally leave the plates on our equipment, so we need several plates. The Bogen heads come with a quick release system including a plate and additional plates can be purchased. If you have a ball head system, we would encourage you to check out the mounting plates sold by Really Right Stuff (www.reallyrightstuff.com)-- we feel they are certainly some of the best available. |
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