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December 19th, 2009, 11:40 PM | #1 |
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Vibration dampening for your video tripod
I've spent a couple of long days shooting video of the sawmilling process - from cutting down the trees to the finished timber (lumber) at a hardware store.
At the sawmill itself, a lot of the shots were taken from the gangways that are used to move around between the various processing areas. Invariably, these walkways are attached to the side of the machinery and vibrate constantly, with extra thumps every time a log goes past. This presents image stabilisation issues. I must say that the image stabilisation internal to my V1 (normal mode) has done a fantastic job, but every now and then the "log level" bumps make it through. My question is .... does anybody have suggestions as to how I can suppress the vibrations? I was thinking of having something to place under each of the tripod legs which would give a cushioning effect. Mini beanbags? Shock absorbers for tripod legs? Andrew |
December 19th, 2009, 11:53 PM | #2 |
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never tried or thought about this but borrowing from my audio engineering days...I used (and still use) thick neoprene pads under all my speakers in the studio and now they sell products specific for speaker dampening. For a tripod, you could make pads from layers of neoprene. I'd imagine you'd want them pretty thick (maybe 1-2") and large enough to not wobble.
Try this place: closed-cell foam, slow recovery memory foam, qualex foam, polyethylene, neoprene, polystyrene, EPS, Let us all know if this works!
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December 20th, 2009, 12:32 AM | #3 |
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same thing here, i glued a 1/4" premium ply boards on both sides of pillow foam, which is closed cell, then screwed in reciever cups into the center of the boards, the cups keep the wheels from falling out. . . . on my Bed :-) ok weird application but it isolated the bed from the floor, and by making a foam Sandwitch i had a way to get the castors from moving off the center. those were 1x1' size far bigger than you would need.
for a tripod in the conditions you mentioned i would probably go with softer foam, and not closed cell which maintains its shape longer. nor would i use memory foam as its main feature is to maintain its shape, you would want more give constantally/instantally. the Ideal foam weight and foam ammount of the foam sandwitch size, would be that the foam is 1/2 crushed at the standard weight that you have on it. that way any vibration up or down the coushin would be Mid the total throw, giving you the most range. if the sandwitch has to much lift, you could just bandsaw its size down till it had the right ammount of give. once you get the right combo, make 100 of them mark up the price $15,000 and you can sell them to video people world wide :-) we use 2x thick mouse pads glued together for floor mic stands, to keep foot clump out of the mics. just like the sandwitch having the fabric on both sides keeps the foam from falling apart inside.
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December 20th, 2009, 02:38 AM | #4 |
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Astronomy accessory
Serious amateur astronomers are concerned about vibration of their high-powered telescopes. Both Celestron and Meade make vibration-suppression pads to put under your tripod legs.
Celestron: Celestron | Vibration Suppression Pads | 93503 | B&H Photo Video Meade: Meade | Vibration Isolation Pads | 07368 | B&H Photo Video I think they're mostly for higher frequency vibration, but might work for "log level" bumps. Ken |
December 20th, 2009, 07:08 AM | #5 | |
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Quote:
I know that some CMOS cameras can have a real problem with high vibration situations -there's an example here : YouTube - CMOS vs 3CCD Heavy Vibration Test Hopefully Sony have a faster sensor scan speed than Canon - it would be nice to know that you can use CMOS sensor cameras successfully in this kind of situation, especially with CCD cameras becomong increasingly hard to find! |
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December 20th, 2009, 07:12 AM | #6 |
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This is all very interesting. Really valuing the feedback thus far.
FWIW, for "log level" you feel the jolts in your own legs, let alone the camera. Tend to visually notice it most when you are zoomed in on something. I'm wondering if I need to somehow invent the tripod equivalent of the shock-mount that is used in a microphone blimp. After all, I have a spare set of rubber rings (thanks to the generosity of those Rode guys) and that will be enough to cater for two legs. Might be able to politely ask them for more rings for the final leg. Then it would be just a matter of some items to string the rings between - a base and a leg holder / pivot thing. With the blimp you get a set of different sized mic holder things with a hook already attached for the rings. Those holder things are pretty much round-ish, and should do the job for having something to mount the tripod leg into. Just got to have a base. This could be the hard part. Any further suggestions? Andrew |
December 20th, 2009, 07:16 AM | #7 |
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Hi Roger,
Only just noticed your post. So far no jello-vision on the V1, with the possible exception of the really big "log level" thumps. But even a CCD would have a hickup with that sort of thing, I suspect. From memory, I had the shutter running at 25fps and shooting 1080 progressive (PAL). I'll have to register a second Vimeo account (for technical testing footage purposes) and upload some of the footage. Andrew |
December 21st, 2009, 01:28 AM | #8 | |
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I've had some success putting a sand bag under each leg of the tripod to stop a shaky floor ruining shots. |
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December 21st, 2009, 01:34 AM | #9 |
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Actually, I did have some thoughts of mini bean-bags under the tripod legs. It's a matter of what will absorb the right vibration frequency (and be able to handle the amplitude of the movement).
It's all very interesting. Andrew |
December 22nd, 2009, 01:21 PM | #10 |
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Andrew,
We are having a similar problem when zoomed in, but, our units are ceiling mounted, and when the HVAC is going, get a bag..... still working on this too.
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December 22nd, 2009, 05:51 PM | #11 | |
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they use the bungie rubber type stuff like a mic isolator. but would be for about 75Lbs each. If after you isolated the pod, you still are transferring shock from yourself , a pair of these (size 9 max shoe) would isolate yourself too :-) that would be so funny seeing a videographer walking in with a full isolation mount system DIYed i would want to see a video of it after. with Mics and cross rubber iso mounts, any Bounce induced wouldnt effect the audio, but putting rubber bounce on a video , would just change the shock from fast to slow and bouncey. Car shock adsorbers have the oil dampeners in them so spring like adaptions to the changes of the road dont turn into continual bounces. which brings back memory foam, memory foam would have the give and bounce, and of all the things it would Also have the oil dampners sort of. that might make it better than i originally thought.
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December 22nd, 2009, 11:33 PM | #12 |
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Even more so ... what would the client think of a video guy turning up in moon shoes???
The good news for the moment is that I mentioned the vibration issue and the client is fully understanding as he already knows that the whole building shakes with what is going on. Still, if it goes well, there are other company sawmills that need to be videoed. So I'll still be working on the vibration issue. Andrew |
December 23rd, 2009, 06:41 AM | #13 |
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Trying to stop vibration is not a trivial matter. Efforts to stop it can make it worse if the damping / suspension system is not critically dampened. The gent who had the Meade vibration pads gave me another example of some of those kinds of problems. Some of the tripods he sells for telescopes can resonate quite nicely as can some the telescope bodies.
I think the good news is if you can dampen the faster vibrations and limit the acceleration of the camera then the OIS has a good shot at handling the rest of the problem. |
December 23rd, 2009, 11:54 AM | #14 |
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there are not so many ways to stop vibrations:
inertia: use a 250Kg platform to put your tripod on. Pro: will work well Con: impossible to move it. variation: use a water bed, so you can fill it on location. isolation: use magnetic field to lift a platform, stabilize with some opto-electronic device. Pro : able to sustain any vibration Con: very hi-tech stuff , probably impossible to manage, require huge manetic field. Variation:can replace magnetic field with springs, but then it become even more difficult to manage. if the floor is vibrating, why not use the ceiling to suspend camera ? or wall ? You can also minimize vibration transmission, by setting the tripod on spikes, then spikes on some isolating rubber. |
December 23rd, 2009, 03:09 PM | #15 | |
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some crasy things got a lot of attention (be it good or bad) and of course displayed my great dedication to the job (not to mention my inability to purchace the right stuff)
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