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Evaluating Tripods

by Roger N. Clark

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Before I get into choosing a tripod, some imply one can't get a sharp image without a tripod. With today's digital cameras and image stabilized lenses, hand held photography can deliver images just as sharp as can be done on a tripod. Professional and advanced amateur photographers are even obtaining astounding, tack-sharp images with super telephoto lenses hand held, even at focal lengths of 500, 600, 800,1000 mm and more. I do more and more photography these days hand held, especially action images with telephotos.

A key is understanding when you need a tripod. With fast exposure times, hand held is fine. The 1/focal length guide is reasonable and can be pushed several more stops with image stabilized lenses.

The 1/focal length guide was developed for film. Digital with small pixels need to consider pixel size (crop factor is not the correct metric). My equation for digital cameras:

hand-held exposure guide: 1/(8 * focal length in mm / pixel size in microns)

For example, a Canon 30D with 6.4 micron pixels has the factor in the denominator = 1/(8 * focal length /6.4) = 1/(1.25 * focal length) so a 50 mm lens should have an exposure time of 1/60 second or faster. With an image stabilized lens, one can be 3 to 4 stops slower, or 1/7th to about 1/4 second. Cameras like the Canon 7D and T2i have 4.3 micron pixels the 8/pixel size is 1.9 or about 2.

However, as light levels fall, or one needs to stop down for high depth of field, a tripod can certainly make a difference. And certainly people's abilities to hold a camera steady varies, so modify the above equation to your ability. If you shake more, increase the number (the 8) to a larger value.

When choosing a tripod, extend the legs, grab the head and twist. Note how much twist in each one. Put a big camera with big lens on it and tap the legs and watch and feel the vibration. Most tripods are pretty poor. The carbon fiber will be the best. Test a Bogen 3001, and 3021 for reference. A 3001 is kind of the bottom in my opinion for a quality tripod and with a consumer DSLR such as a Canon 20D, 30D, 40D, 50D, etc and a 70-200L lens might show some shake, and definitely will at slower shutter speeds with with a 2x extender on it. Then test a carbon fiber (CF) tripod, like a Gitzo 1228 and it is an amazing difference. The carbon fiber rapidly dampens vibrations.

When choosing a tripod, understand that a tube design is the best. Square, rectangular, and open (e.g. U-shaped) legs are less stable, with the open design the worst. I will only consider tripods with telescoping tubes for the legs.

One needs to understand tripod vibrations. Set up your tripod before sunset and take an image of the same scene in aperture priority mode where you keep the aperture the same and only the shutter speed varies. Best to set the aperture to about f/8 and an ISO that gives an exposure time faster than the hand-held exposure guide value. Image every few minutes until exposure times are a few seconds or more. Examine the results. You will likely find there is an exposure range, (usually in the 1/20 to 1 second or so) that are less sharp than other exposure times. Try this again on another night only do mirror lockup first before each exposure and a cable release. The range, if any, of less sharp images will be much smaller. Then simply avoid those times when you image. Or buy a better tripod.

A better tripod, including CF tripods, will have a narrower range where sharpness is compromised. But change lenses, (e.g. telephoto versus wide angle) and the situation changes and you need to test all over again.

For very long exposure (seconds) or fast exposure (faster than the guide: 1/8*focal length/pixel size) even low cost tripods can perform well. But I will conclude that CF tripods dampen vibration faster than aluminum tripods and are worth the cost if you work in the 1/20 to 1 second range a lot (and a little faster with telephoto lenses).

In the 1990s. when I started getting drum scans of my slides, I was seeing blur in the scanned images. I analyzed what did it and it turned out to be the tripod. I upgraded to Bogen 3001, then 3021, then carbon fiber. The CF was a big jump in stability, but at a much higher price.

I found I can do better with a Gitzo 1228 CF than I can with a Bogen 3021 aluminum tripod. Metal 3021 legs vibrate. The 3021 (8 lbs, 3.6 Kg) has an 11 pound load capacity while the Gitzo 1228 weighs 3.8 lbs (1.7 Kg), and has a load capacity of 17.6 pounds. I have both, and the 1228 is much more stable at half the weight. Just an example.

The Gitzo 1228 and Bogen 3021 are now out of production but newer models are equivalent in performance. The 3021 equivalent now appears to be the Bogen Manfrotto 055XPROB Black Pro Tripod. The Gitzo GK2580 series seems to be somewhat equivalent to the 1228.

Key in buying cheap light tripods is throwing away the cheap plastic head and putting on a better head. Better, though, is buying carbon fiber legs and a good head.

For a head, be sure it has a quick release plate system, and one that if you release the clamp, the camera will not slide off or fall out of the clamp. This is VERY important. After going through several clamp systems, there are only two I like: the arca-swiss style that Wimberly puts out that has screw stops to prevent sliding out, and a Bogen 329 head (Manfrotto 3410). The 329 head has the highest camera load/head weight ratio in the Bogen line of pan/tilt heads (the last time I checked) and has a quick release with a safety stop. For big telephotos, I use the Wimberly heads (sidekick for up to 300mm, full Wimberly for 500mm f/4).

For a super light but amazingly sturdy ball head is a Giotto MH 1302. Only 12.5 ounces, yet hold a havy pro DSLR and big fast lenses like 35 mm f/1.4.

It all comes down to understanding your equipment and working around any limitations.

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First Published August 14, 2011
Last updated September 14, 2012