While the torsion test is an excellent tool, it would be useful to have a test that more directly relates to the sharpness of images coming out of the camera. I am going to duplicate the razor blade mtf test developed by Jim Kasson. This test takes an image of a single back-lit razor blade, […]
Read MoreMonth: January 2018
Deflection of Test of RRS TFC-14
In the last post I described how to make a deflection measurement on a tripod, and here we will do just that. I am going to test the same Really Right Stuff TFC-14 tripod used in the torsion spring frequency test, which will allow us to compare and contrast the two methods. The basic idea […]
Read MoreDeflection Testing
I have a series of posts going on using the vibration frequency of a tripod to measure the stiffness and damping characteristics. I am now going to lay the groundwork for a related but different type of test, the deflection test. I have found this test used, albeit somewhat dubiously, by one tripod manufacturer. The […]
Read MoreConsistency of the Torsion Test vs Inertia
In order for the torsion spring test described here to be meaningful, it must be both repeatable and applicable over a broad range of conditions. In this post, we will look at the results of stiffness and damping measurements over a range of inertial masses placed on top of the tripod. With more inertial mass, […]
Read MoreRadial Torsion Spring Test
In previous posts I described modeling a tripod as torsion spring, and demonstrated the validity of that approach. In those posts though, I was only looking at vibrations about the vertical axis, corresponding to the camera pointing left and right. Here I want to take those same methods and look at tripod rigidity about a […]
Read MoreMeasuring the Stiffness and Damping of a Tripod
In the previous post, I discussed the rationale behind modeling a tripod as a torsion spring. Here, I am going to measure the stiffness (spring constant) and damping of a tripod and discuss in detail the methods and assumptions made. As a warning, math will be involved for complete clarity of the procedure. It is […]
Read MoreThe Torsion Spring Framework
After some exploratory testing, it is clear to me that the route to repeatable and comparable testing of tripods runs through the damped torsional harmonic oscillator model. If you are curious on the details the wikipedia article on the subject is thorough. However, I do not intend to make differential equations a prerequisite for understanding the testing […]
Read MoreOrigins
The Center Column is my attempt to document the search for the ideal tripod. The internet is alive with well documented testing of cameras and lenses, but there is not a cohesive set of information on the performance of tripods and heads. In fact, I couldn’t find any set of repeatable measurements on the stiffness […]
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