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carleton
29-Oct-2010, 02:51
I need to take a long exposure (2-5 mins) from a steel gantry in a factory but the movement of cranes etc makes the entire building - and gantry - vibrate. The frequency and extent of the vibrations is not uniform and varies according to the particular movements of plant. Does anyone know how to counteract the vibrations? One idea is to adapt snow shoes for the tripod feet and place these on large bags filled with polystyrene chips etc as vibration bafflers. Any suggestions, please?

Walter Calahan
29-Oct-2010, 04:21
A wood tripod is also part of the solution for its superior damping, but I like your ideas to add a buffer to the bottom of the tripod legs so long as stability is not compromised.

neil poulsen
29-Oct-2010, 18:36
I took photographs for a company of targets along a river bank from a small tugboat. It was a fun project.

Of course, the engine vibrated the entire boat. So, I made three vibration absorbers, one for each leg of the tripod. Each was about 4"x6" and consisted of four layers. The top three layers were of a moderately stiff, half-inch thick foam rubber. The top layer of foam rubber had about a 2" hole for the tripod foot. The bottom layer of the four was a thick piece of shag carpet. I glued all four layers together. The three layers of foam were glued onto the back of the shag carpet, so that the shag interfaced with the boat's deck.

This worked great for this application. The photos came out very sharp.

But, I wonder if this approach would work for your situation? I was dealing with high frequency, low amplitude vibration through the metal floor. Your situation sounds more like low frequency vibration at possibly high amplitude.

argos33
29-Oct-2010, 19:14
I remember reading in a macro photography book that an inner tube with a heavy slab/surface on top makes an excellent vibration dampener. Perhaps you can find a wide bike tire, and put a 1" thick piece of MDF or something on top. Then put the tripod on top of that?

Frank Petronio
29-Oct-2010, 22:52
Four old CAR tires and a 4x8x3/4 plywood on top. Add concrete blocks for weight to the plywood to "tune" it until you can't feel any vibration.

IanG
30-Oct-2010, 04:39
You asked the same question last month and had plenty of answers :D

Ian

GPS
30-Oct-2010, 04:42
You asked the same question last month and had plenty of answers :D

Ian

It was a test...;)

Robert Hughes
2-Nov-2010, 11:53
Four old CAR tires and a 4x8x3/4 plywood on top. Add concrete blocks for weight to the plywood to "tune" it until you can't feel any vibration.
That trick's similar to how they used to make audio recording studios in the 1940's. Those old Conway Twitty records were done in studios with floating floors like this.