Reader Question: “how the weight of a ball head or geared head might correlate with stability of a tripod”
Related: Acratech, Brian K, exposure, gear, Jason W, long exposure, Novoflex, reader comment, Really Right Stuff, Roy P, tripods and support
It’s the last day of fishing season here in California and it’s been so wonderfully warm that I wish I were up at Saddlebag Lake catching Brook Trout like this one.
Anyway, onto the topic.
Reader Roy P writes:
I have a curiosity question on how the weight of a ball head or geared head might correlate with stability of a tripod. The old trick is to hang a backpack or some weight on the hook many tripods provide at the base of their apex or center column to improve stability. I have never found this to be a good solution in windy conditions, since the backpack ends up adding more surface meeting the wind, and can swing. But I suppose it would help if a truck drives past you while you’re doing a long exposure.
For example, what if you use a heavier head instead of a hanging backpack? With the same tripod, will a heavier head provide more stability? As an example, would a medium weight tripod like a RRS or Gitzo Series-2 be more stable with a ball head like the RRS BH-55 (1050 grams / 2.3 lb) than with a ball head like the RRS BH-40 (910 grams / 1.44 lb)?
A different example: The Novoflex PRO75 tripod weighs 3180 grams (7 lbs), and is very stable. I used to own one, and I’ve used it for long exposures of The Milky Way with a tracker, and the tripod was rock solid. What is interesting is, just the apex of the tripod, which Novoflex calls the TrioPod PRO75 Base, weighs 1300 grams (2.8 lbs). Novoflex uses a modular design, so you could use this apex with a set of thinner legs like the Novoflex QLEG C2844, which collectively weighs 975 grams (2.15 lbs), so you could have a lighter tripod that weighs a total of 2280 grams (5 lbs) that is potentially a good compromise between weight and stability?
Let me know what you think, or if you have experimented with something this.
DIGLLOYD: the dominant issue is not the weight of either the ballhead or the tripod, it’s the resonance. I spent a week or so looking into tripod and balhead behavior years ago. At a high level, the results showed clearly that tripod weight and/or ballhead weight had only a modest correlation.
It’s all about resonance—how vibrations and shocks propagate through the rig as a whole and in particular the support right under the camera. It means, for example, that wooden tripods might be quite a lot better than carbon fiber, but that would of course depend on the right type of wood and how it is used. And... wooden tripods are rare and expensive and heavy.
Avoid tripods with vertical columns; these jiggle if anything is going on eg light wind.
100% magnified Live View tells you almost all you need to know…. watch it with a fan going, or tap the lens lightly, or practically just puff on a long lens, trip a mechanical shutter, etc.
The tripod foot on super-teles is a lame-brain design—you can have a 500 pound tripod and 50 pound ballhead, and it won't matter because the lens is essentially a teeter-totter design. Compare the solid-block tripod foot abutting the lens barrel on the classic Nikon 50-300mm f/4.5 and it's a vastly superior design, one long abandonded for the modern see-saw teeter-totter anti-design of modern telephoto lenses.
Makes sense. There must be all kinds of acoustic refractions, reflections, total internal reflections at every metal-to-metal interface, like the tripod to the apex / top plate, apex to ball head, ball head to clamp, clamp to plate / bracket, then plate to camera, the finally, camera to lens. If a leveling base is used between the tripod and the head (e.g., geared head), that would be yet another interface. Even within the tripod, you have multiple segments and connectors. That’s an awful lot of mechanical connections.
Most of the tripod accessory products are advertised as using “aircraft grade aluminum” for even the cheapest Chinese products. So I don’t know if Aluminum-to-Aluminum joints improve resonance.
Perhaps it’s best to get a tripod and as many of the related components as possible from the same manufacturer – presumably, the products would have been tested interoperating with other components from the same manufacturer.
DIGLLOYD: I doubt that interoperability testing for resonance is a thing. Or any resonance testing at all, from what I can tell (lots of very poorly damped offerings out there).
See my tripods and ballheads wishlist and my Acratech and Really Right Stuff pages.
I have a dozen or so tripods and many tripod heads. My standard setup for hiking and general use, which I rarely switch-out unless other requirements exist, is the Acratech panoramic head on the Really Right Stuff TFC-24L.
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Jason W writes:
I merely dated a structural engineer so I'm talking out of my posterior, so please correct each of these statements according to your thinking...
Mass of a tripod is more relevant for strength, ie. there's no material we have to make a 1 lb tripod that can support a 100 lb Panavision camera. That being said, assuming you have a sufficiently strong tripod for your camera+head
If we're talking about tripod legs, you want a material with a high Young's Modulus which does not deform under stress. Ie. You wouldn't want the legs to be made of rubber.
But you still need damping, or else your rigid legs transfer your wind energy up the tripod and to the camera. The internal structure of the material, and all else being equal, more surface area of that material, usually in the form of wider diameter tripod legs, aids in dissipating the wind energy. Also having round legs that are aerodynamic moves air around the tripod so the environmental energy is never transferred to begin with.
I've never tested this theory, but with telescoping tripod legs, the leg sections get progressively thinner as they collapse. Therefore, my assumption is fewer sections are better for vibration reduction because it increases the relative sizes of your leg sections. Starting from the same top section, I assume a 3-section tripod is more stable than a 6-section with tiny legs at the bottom. That being said, I'm not sure how much damping the locking parts on each section add, and if it balances out the smaller sections with more locking points.
As for the heavy head or light head, it's probably not relevant for vibration because the head is ideally not the majority of the mass in a tripod configuration, otherwise you'd get a dangerous top heavy design.
DIGLLOYD: probably like what Hubert Nasse once said to me about optical design: “it is the sum of everything”.
A slight deformation might help damp vibration, I would think.
I found that larger diameter is not very helpful for vibration and that smaller tripod legs could damp better. But I am not claiming that as a general thing as it’s the sum of everything and a complex system.
My guess is that the joints probably dominate, not the legs eg what happens between one leg section to another.
With wind, I can feel all sizes of tripods vibrate in the wind. But I would tend to agree that larger/heavier legs generally do better in the wind. OTOH, they have a larger area, so much more force on them, so maybe not! But in any significant wind, 100% magnified Live View quickly shows that the image is not stable.
Assuming one has a head and camera in a stable configuration, my guess is that rubber leg wraps might help.
Brian K writes:
I read the reader email related to the weight of a tripod head and stability and wanted to share a tip with you.
I know many people will hang a bag or a weight from the hook under the apex of the tripod but as you pointed out that will tend to swing in the wind.
I do a lot of very long exposures so what I do instead is loop a bungee cord around the three legs and then hang another bungee cord from it that connects to all three centers between each leg of the looped bungee. This way all three legs will have equal tension applied to them. I then connect that hanging bungee to a sand bag or lead shot bag which sits on the ground. The hanging bungee is taut and creates downward pressure but also acts as a damper and is not affected by the wind.
The trick is to have the right amount of tension, you want it taut and creating downward pressure but not overly tight.
DIGLLOYD: interesting idea!
