Tripod stability
I usually use a tripod as a light stand at an outdoor shooting (*1). The wind is my biggest enemy because it knocks down the tripod as soon as I attach a light diffuser (like an umbrella) to the flash. What I didn't understand was why the tripod seems to topple over no matter how much weight I add to the sandbag.
The hook for the sandbag is usually on the tripod's center column. I thought attaching the weight at the end of each leg would lower the center of gravity and make it more stable.
In the pictures below, I'm pulling the top of the tripod to the right (as the wind would do) with a luggage weight scale. [Left] has three water bottles hanging on the center column. In [Right], I attached one bottle to the end of each leg using hook and loop, how much more force does it take in [Right]?
The answer may surprise you ;)
If you want to feel "OMG! I used to be able to do math in highschool!" like I did, please give it a try yourself (see Appendix below).
Then I realized the difference is in the work required for the wind to tilt the tripod up to the tipping point. As you can see the tripod can tilt much more in [Right] before it starts to topple. So the solution is to attach a weight to the end of each leg using a tape or hook and loop. You can use wrist weights, canopy weights, etc. as well.
When doing that, you have to make sure the tripod stays open when it is tilted. The tripds with struts like this are fine. Otherwise you have to add your own struts. (In the pictures above, you see my white 3D-printed spacer that is keeping the tripod open.)
My ultimate solution was to use
rebar with hook and loops at each end.
They are heavy but they fit in my tripod bag.
With those rebars attached, my tripod never even tilted during a shoot at the very windy beach :)
(*2)
Notes: (*1) Regular light stand cannot be used on an uneven terrain. C-stands are heavier and only folds into a big "L" shape which won't fit into my tripod bag.
