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Old Nov 11, 2011, 03:56 PM
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United States, MA, Walpole
Joined Dec 2003
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Quote:
Originally Posted by Simcop View Post
Tom, yes I was referring to the "jello" effect... Kinda trippy...At first I thought I was the cam loosing frames, because it seemed to only happen on the horizon, watching closer I figgured out it was just the tape that I used an an expeditious mount hadware buffeting in the wind...kind of like the later half of a flag in strong wind, causing my image wobble. I'm still dealing with the engine vibration throughout the fuselage though...any ideas on how to dampen that? I read somewhere about a "moon jelly"...Right now I just have one layer of foam taped underneath my cam, which helps but I can't test fly two layers on account of wind...Thanks for the help
The first thing you must do is balance your prop (or rotor if a heli). After that, some vibration will almost always remain (e.g. electric motor rotating parts aren't perfectly balanced, and IC engines are much worse than electric motors.). IC engines can benefit from things like rubber washers to isolate them a bit from the airframe, but I don't fly these any more, so have no detailed suggestions.

There is no one solution for a camera mounting method that works on every aircraft to isolate the camera from vibrations. The size, shape (rigidity) and mass of the airframe, where the camera is mounted on it, and the vibration frequency and amplitude are all factors.

One other thing you have big control over is the frequency and amplitude of vibration by virtue of the throttle setting. You can find those spots by mounting your camera on your aircraft as you will when flying, then shoot a video while very lightly restraining your plane so as to minimize as much as possible dampening the kind of vibration it will normally have when flying unrestrained. Then, if your throttle has a spring with detents, advance it one "click" at a time and shout the number of the click so it can be heard in the video. I do this all the way from full off to WOT, then back down, stopping at each click for several seconds so you can analyze the video vibration at each click stop. That can often show a few throttle points where camera vibration artifacts are minimized if not eliminated. You can then (hopefully) fly at those points (if not with throttle full off) for best results. If your throttle spring has no detents, it's tougher, but might still be done by referencing the approximate position of the throttle stick audibly in the video.

What seems to work best for me is using an isolation pad of some sort between camera and airframe (I used small bubble wrap padding or soft EPP foam padding I've salvaged from shipping container packing), then compressing the camera against that very firmly (e.g. tight wrap of tape, tightly stretched rubber bands, etc.) Other methods work for other people... you just have to use trial and error to find what works best for you, and that may not work from one of your planes to the next! Good luck finding your best solution.
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Last edited by Tom Frank; Nov 11, 2011 at 04:06 PM.