I don't have the facilities to perform tests as in https://thecentercolumn.com/ but one can gain an impression of the comparitive rigidity of two or more tripods by performing a simple test.
Tripod rigidity plummets with increasing height, so adjust to identical field heights by adjusting only the bottom leg sections. This height can easily be reproduced if one marks the bottom legs with a soft pencil (graphite is a dry lubricant so will not cause any damage). The height should be your own height minus 30 cm for a straight scope or minus 50-60 cm for an angled scope.
Grab two legs about 30 cm below the apex and try to twist the tripod about the vertical axis (i.e. the centre column axis, if there is one). In most cases one can achieve a significant deflection.
For the record, my results were as follows:
1980s Aluminium Gitzo Series 4 with 37, 32 and 28 mm leg sections. No felt deflection and visibly perhaps around 1 mm in the middle of the legs.
Carbon fibre Sirui M-3204 with 32, 28, 25 and 22 mm leg sections. Very noticeable deflection compared to the big Gitzo.
Novoflex TrioPod with 2830 carbon fibre legs of 28, 25 and 22 mm diameter. Noticeable deflection but my impression was that it was somewhat less than the Sirui. This was surprising as I had to extend the 22 mm bottom leg sections further. Externally the tubes appear to be very similar and are probably also Chinese sourced.
Basalt fibre Gitzo GT2942L with 28, 24, 20 and 16 mm leg sections. This tripod is about the same weight as the Sirui but deflects two or three times as much under a similar load. Not surprising that Gitzo have now abandoned basalt fibre.
Damping can be observed through a mounted scope at higher magnification by rapping one of the tripod legs. However, I doubt that there would be significant differences between similar tripods of the same material. The trick of hanging the strap of a loaded bin bag over all three legs noticeably shortens vibration decay.
John
Tripod rigidity plummets with increasing height, so adjust to identical field heights by adjusting only the bottom leg sections. This height can easily be reproduced if one marks the bottom legs with a soft pencil (graphite is a dry lubricant so will not cause any damage). The height should be your own height minus 30 cm for a straight scope or minus 50-60 cm for an angled scope.
Grab two legs about 30 cm below the apex and try to twist the tripod about the vertical axis (i.e. the centre column axis, if there is one). In most cases one can achieve a significant deflection.
For the record, my results were as follows:
1980s Aluminium Gitzo Series 4 with 37, 32 and 28 mm leg sections. No felt deflection and visibly perhaps around 1 mm in the middle of the legs.
Carbon fibre Sirui M-3204 with 32, 28, 25 and 22 mm leg sections. Very noticeable deflection compared to the big Gitzo.
Novoflex TrioPod with 2830 carbon fibre legs of 28, 25 and 22 mm diameter. Noticeable deflection but my impression was that it was somewhat less than the Sirui. This was surprising as I had to extend the 22 mm bottom leg sections further. Externally the tubes appear to be very similar and are probably also Chinese sourced.
Basalt fibre Gitzo GT2942L with 28, 24, 20 and 16 mm leg sections. This tripod is about the same weight as the Sirui but deflects two or three times as much under a similar load. Not surprising that Gitzo have now abandoned basalt fibre.
Damping can be observed through a mounted scope at higher magnification by rapping one of the tripod legs. However, I doubt that there would be significant differences between similar tripods of the same material. The trick of hanging the strap of a loaded bin bag over all three legs noticeably shortens vibration decay.
John
