Three Section Tripods vs. Four Section Tripods

[ben_johnson10]

I was curious about the commonly used rule of thumb, that given all other characteristics are the same,

that a three leg section tripod is sturdier than a four leg section tripod.

 

I wonder if this rule is still applicable to the modern line of Gitzo 6X CF tripods with the G-Lock feature?

 

Has anyone seen any reports or tests of the new G-Lock comparing a three section to a four section

tripod?

 

I wonder if folks continue to use this rule of thumb simply because "it's always been done this way"?

 

Just curious.

[brucecahn]

And a two section sturdier than a three. Also less affected by vibration.

[gdanmitchell]

The "sturdiness" issue is one thing to think about. Another is that it adds a bit of extr work

to setup when you have to release, adjust, and lock three additional sections.

 

One section legs would probably be ideal, except that reality gets in the way. Most of us

couldn't carry around such huge tripods. Sometimes we want the camera to be lower to

the ground. So we compromise. In many cases where small

packed size isn't critical, three-section legs provide a good solution.

 

My main tripod is three section, but I also have a smaller 4 section unit for travel and

backpacking.

 

Dan

[pvp]

Fewer sections mean fewer leg joints to wobble, hence the odds are that a tripod with fewer sections will be sturdier. More sections might be more wobbly and will certainly take longer to set up and take down, but will also fit into a smaller space. Everything is a tradeoff...

[craig_gillette]

When you look at the fit and tightness of the overlap in Gitzo's, one might wonder, absent real testing, if the 4th joint actually improves vibration damping - the different cross sections and section lengths will almost certainly have different responses to different types of vibration. Of course all of this is supposition short of doing real testing in a lab with a variety of frequencies and amplitudes. The smaller diameter 3 section tripods may perform worse than the larger 4 section tripods even with the same loads.

[ben_johnson10]

My thought was that the old rule of thumb for "less joints= less wobbly tripod" came

about because many of the older designs of tripod leg joints, were/are very loose designs

so the old rule of thumb makes sense.

 

However, eventually some clever manufacturer will come up with a design that is so

mechanically secure, such that there would be no difference between a continuous leg

design and a multi-joint design.

 

I was wondering if the Gitzo G-Lock was such a design; I'm not sure if anyone's done any

testing already.

 

Do we automatically say to ourselves "less joints= less wobbly tripod" just because "that's

the way it's always been", or should we challenge this and re-evaluate it?

 

I'm beginning to wonder if this old adage has outlived its usefulness?

[images_in_light_north_west]

Less joints is better

[pvp]

<I>Don't Bogart that joint, my friend...</I>

[Ed_Ingold]

Gitzo tripods already have a joint design which is nearly wobble-free. Each leg section is a close fit with the upper section, and has two "piston rings" with a clearance of about 0.003 inches. There is no noticeable wobble in a fully extended leg even before the collar is tightened. The tubing is hard-drawn and machined to dimension, about 1.5mm thick.

 

The smallest leg section in a tripod determines the stiffness for a Gitzo tripod. I find that a 4-section, series 2 aluminum tripod (G-1226) is too wobbly for a 200mm lens in a light breeze, whereas a 3-section version (G-1224) is more than adequate. A 3-section CF G-1227 is about as stiff as an aluminum 3-section G-1340.

 

For comparison, a Bogen/Manfrotto tripod depends almost entirely on the locking mechanism for stiffness, and the tubing is soft and much thinner than for a Gitzo. You really get what you pay for.

[ben_johnson10]

Edward: I thought the modulus of elasticity of carbon fiber was much greater than that of

say, 6061-T6 aluminum? Isn't the stiffness of composites what is always touted by

manufacturers using them in aerospace, recreational, auto racing etc. industries?

 

I'm not sure about the cross-sectional differences in the aluminum vs. the carbon fiber

tubes, but all dimensions being equal, I would think the carbon fiber tube would be stiffer

due to its higher modulus of elasticity?

 

If the G-Lock joint design effectively makes all the leg segments behave as a single leg

segment, and the superior stiffness of the carbon fiber is utilized, I would think the old

adage of "more joints = wobbly tripod" is no longer applicable.