The Sirui T-025X is one of the lightest and most compact travel tripods available. The whole thing folds up to less than a foot in length, including a ball head and weighs less than two pounds. This is better than most tabletop tripods. As expected though, the stiffness and damping characteristics suffer. This is a tripod where good technique and favorable conditions will be necessary to avoid inducing any vibrations.
| Name | Sirui T-025X |
|---|---|
| Class | Travel |
| Stiffness About Vertical Axis | 140 +/- 2 Nm/rad |
| Damping About Vertical Axis | 0.094 +/- 0.009 Js/rad |
| Stiffness About Radial Axis | 385 +/- 3 Nm/rad |
| Damping About Radial Axis | 0.257 +/- 0.026 Js/rad |
| Retail Price | $200 |
| Weight | 1.49 lbs (0.674 kgs) |
| Manufacturer weight rating | 13.2 lbs |
| Maximum Height | 37.2 in (94.5 cm) |
| Minimum Height | 4.0 in (10.2 cm) |
| Max Height with Center Column | 50.9 in (129.3 cm) |
| Center Column | Yes |
| Base Diameter | 1.4 in (3.6 cm) |
| Folded Length | 11.9 in (30.2 cm) |
| Folded Circumference | 9.9 in (25.1 cm) |
| Folded Volume | 93.0 cu. in. (1.5 liters) |
| Leg Material | Carbon Fiber |
| Leg Sections | 5 |
| Primary Leg Angle | 26.0 deg |
| Leg Locks | Twist |
| Top Tube Diameter | 22.0 mm |
| Second Tube Diameter | 19.0 mm |
| Third Tube Diameter | 16.0 mm |
| Fourth Tube Diameter | 13.0 mm |
| Fifth Tube Diameter | 10.0 mm |
| Exchangeable Feet | No |
| Foot Type | Rubber |
| Bottom Hook | Yes |
The stiffness and damping data are the averages of 10 trials for each measurement. The reported error is the standard error, except in the case of the damping data. I have set the error in the damping at 10% as the standard error metric does not appropriately capture the error in fitting to the data. All of the reported specifications are measured, with the exception of the weight rating. The tripod is measured at full height, with the center column down.
Special note for this tripod: The center column is removable and weighs 69 grams. The stiffness measurement was made without the center column attached, but the reported weight includes the center column. The tripod also comes with a small ballhead. These data are measured without the ballhead to provide a more direct comparison with other tripod legs.
Example data for oscillations about the vertical axis of the tripod:
Data doesn’t get much nicer than that. We are very clearly getting a clean resonance. But both the stiffness and damping are poor.
Example data for oscillations about the radial axis of the tripod:
This is more of a mess. The frequency fit is initally good, but then clearly not so much as the oscillations die down. This is a clear example of some non-linear behavior in the system. It appears as we are underestimating the damping some as well at the larger oscillations.
Also a mess. But it appears we are getting the right line right around 9.6 Hz.