Cal Club Autocross Forums

I just sprung for a cheapo wireless video cam (Oregon Scientific ATC 3K) and it has a variety of mounting options. From experimenting, the one that seems to work best is velcro-strapping it to my driver's side mirror. Would this setup pass tech? The camera mount has a rubber foot, so the camera stays very tight and secure against the surface of the mirror.

I think it would be fine... Your SSS experience may yield conflicting outcomes.

The main things we look for are NO handheld cameras.

And we look for a tether for the normal screw in the bottom mounts. Why? Because under autocross loads, that little screw hole will rip out of the bottom of your shiny new camera.

under autocross loads, that little screw hole will rip out of the bottom of your shiny new camera

Somehow I doubt that. Maybe I have a totally wrong impression of g-force but I don't think we pull several Gs out there unless we hit a pole. To rip a metal screw out I think it would take more force than 2 or 3 times the weight of the camera. If you can give it a good tug and nothing budges, you're fine. The biggest problems come from vibration - stuff has a way of coming loose. Again, just make sure everything is tight. If the camera is like most of those I've seen, a good wad of chewing gum would do the trick. (jk)

t

Its not a theory. It has happened in SCCA autocross. That is why the word went out to require tethers. It might be a metal screw, but often its mounted in some cheap thin brittle plastic.

the word went out to require tethers

More useless nanny-state regulations. The same physics applies to the entire car. How many feet/pounds of torque will the unit withstand? Since it's only in contact with one surface (not bridging two), it's easy to figure out because it only has its own mass to act as a force multiplier. Do we pull more than 2 Gs out there? Its pretty easy to replicate in Tech that much force or more over something of so little weight. ;)

You're making false assumptions Tom. What are you going to figure out? Do we have the failure limit documented of a plastic upright Acme HD Pocket Recorder from Guangzhou? And inside the car if it fails its a missile at the driver.

I didn't pull it out my ass. It happened. It seems you're thinking about load limits of metal screws. Sorry. The metal doesn't fail. The body of the camera breaks. The threaded nut/receiver stays nicely attached to the screw of the tripod mount. No failure there. The camera has just moved on.

data-

Certain cameras such as the Aiptek which use a threaded insert in a plastic body, do have a tendency to fail at this point. What makes it worse is that a large part of the camera, even if small and light, is sticking up a bit high from the mounting point (high center of gravity... longer moment arm).

Small bullet style cameras do not typically have this problem.

Oregon Scientific cameras tend to jump off of cars and commit suicide because of their video quality.

Tom Tanquary wrote:

The biggest problems come from vibration - stuff has a way of coming loose.

That could contribute to the issue. I don't think it is a metal failure issue. Probably the 'nut' piece pulling out of the camera body.

Nevermind. I see this was covered in later posts. Got to read to the bottom.

Newer cameras, other than pro equipment, come with plastic tripod-screw fittings that don't look suitable for anything other than static condition. The old solid metal design has gone the way of film except in high-end gear. If it's not metal and is made of some kind of composite, like Zytel nylon, that's good as long as it's solidly anchored to the camera body. But those questions aren't easily answered pre-failure.

Isn't Tom saying that these cameras have so little mass that they don't generate much force ... so that their seemingly weak 1/4 20 mounts are hardly stressed. I would be more suspect of poorly designed or implemented attachment devices. We seemingly allow all manners of cameras and attachment hardware. I hardly ever see any leashes being used.

I think the weight of the camera is part of it, but poor design is the, uh, undoing of the cheaper gear.

Poor Design? Probably pretty perfectly designed for it's normal intended use and end user. Who wants a fairly inexpensive digi device that is built like a tank and designed to last "forever," when something better is around the corner. I rather pay less so I can buy a new better one a few years down the road.

In a recent interview with the head of Canon, the gentleman was asked which of their cameras is the "Best." He said the latest one, because technology is changing so quickly.

Mako Koiwai wrote:Poor Design? Probably pretty perfectly designed for it's normal intended use and end user. Who wants a fairly inexpensive digi device that is built like a tank and designed to last "forever," when something better is around the corner. I rather pay less so I can buy a new better one a few years down the road.

In a recent interview with the head of Canon, the gentleman was asked which of their cameras is the "Best." He said the latest one, because technology is changing so quickly.

There's a big difference between the design of my 8mp point-and-shoot Canon, with a likely life of about 2 years, and the 1D. For the money the 1D better include an adequately designed tripod mount. I'd bet the average low-end digi user rarely, if ever, uses a tripod.

The head of Canon said what every CEO will always say: Our newest product is the best.

But the point is that not every consumer-quality camera's tripod mount is created equal. Therein lies the difference between adequate and poor design.

OK, I'll try again..... First of all we are talking about cameras that weigh ounces, not pounds. And I believe the camera in question here is more of the bullet style which doesn't have any real high CG issues. Next, the screw isn't (or shouldn't be) the load point - the attaching surface is unless the load force is perfectly parallel with the screw. If the only contact with the car or mount is the screw threads, you do indeed have a problem - the camera is not properly mounted (just like having loose lug nuts). Anything resembling a camera mount has a surface through which a screw is used to attach the camera to that surface. That area is now the connection and the force is spread across that surface. The moment arm is not the screw interface with the camera unless the camera has come loose from the mounting surface. And still I'd like to know where all this force comes from. If I grab that camera in tech and apply say 10 pounds of rapid acceleration on it (which would be more than several Gs for its mass), where on course would it receive as much unless it gets hit with a cone? If it doesn't break in tech, why would it break on course? I know I only went 2 years in engineering before changing majors, but I don't think this is that difficult. Just because someone somewhere didn't have a camera mounted correctly (or at all, it would seem), the entire world of structural engineering is thrown into question? Maybe we should use welds instead of lug nuts because someone's wheel came off once.

Camera mounting physics? Must be a holiday weekend.

Yes it is. I'm trying to clean my office and I'm bored to tears.

ROTFLMAO...boy did I start a $hitstorm!

Okay, I'll address 'em in order...

And we look for a tether for the normal screw in the bottom mounts

This puppy is cheap. Ain't no screw (or much metal at all on this camera...that stuff's too expensive); it's a plastic shoe that snaps in.

Do we pull more than 2 Gs out there?

My car certainly doesn't The camera weighs less than a half pound, so even if we exerted F1-type g forces, we're still not talking about much.

I didn't pull it out my ass.

True, but you could probably could have, as the camera looks like a sawed-off "marital aid." Yes, it is indeed bullet shaped.

Oregon Scientific cameras tend to jump off of cars and commit suicide because of their video quality.

What, they're just so ashamed at being POSs that they can't take it anymore? I drove around for about half an hour yesterday with the thing secured to my mirror, including a run on the freeway and a few full acceleration and emergency braking tests. Granted, I didn't exert anything near the amount of lateral Gs that I do autocrossing but the thing didn't move at all.

Probably pretty perfectly designed for it's normal intended use and end user.

Looks like it. It's designed for capturing action (aka "extreme") sports like kayaking, skateboarding, snowboarding mountain biking, etc. It's waterproof to 9' and shock resistant and comes with a variety of mounts, including those for handlebars, helmets and various assorted straps and rubber shoes for juryrigging your own mount.

If I grab that camera in tech and apply say 10 pounds of rapid acceleration on it (which would be more than several Gs for its mass), where on course would it receive as much unless it gets hit with a cone?

BIngo. BTW, where it's mounted, if it got hit by a cone, I'd be in some serious trouble, as it'd mean I was either on my side or being pursued by The Cone That Ate Tokyo.

BTW, thanks to everyone for their responses. Helpful as usual!

FWIW, the camera that fell off probably wasn't a bullet cam, but more likely a small camcorder or larger digicam. Also, most consumer tripods are nowhere near stiff enough in their mounts (if you mounted a mini-dv camera to mine, which was the stiffest I could find for under $80, it will move through about 30 degrees of deflection if pushed/pulled).

Whenever I have strapped a video camera in a car, I have used a tether to the tripod, and then also used a strap independent of the tripod (tied to the cameras handle), just in case the tripod itself failed.

Thanks, David. From the above discussion, that was the setup I was going to use: primary mounting with a secondary tether, just in case.

You guys can argue all you want. You can call it nanny stating (sorta find that funny coming from a leftist...Maybe Obama will restore personal responsibilty to society ;) ;) ;) ;) ;) ;) ;) ). But the SCCA has experienced failures of this type. There is a history. There is data. Camera mounts fail.

Are they bullet cameras??? I can't imagine that happening. But something has failed. Back say 5-6 years ago it was a big deal warning people to tether. Haven't heard much lately. Back then there were a lot more heavy mini DV video cameras out there than the sexy Chase Cam style mega cool bullets. I'd never hassle a bullet camera for a tether. But just about anything esle I would want to see a tether.

You can argue it. But if I'm the SSS I'm probably going to ask the event chair to pull you aside and ask you to correct. If you think I'm wrong please prove it by way of the SSC, DSSS, or God and I'll stand corrected---gladly....One less thing to hassle idiots about is always good in my book. I'd just as soon let Darwin police most things. I got better things to do than pick fights. I'm trying to provide information not opinion, not speculation, not rant. I'm trying to inform somebody who doesn't know what they might expect at an event in terms of safety hassle.



}:)

most consumer tripods are nowhere near stiff enough in their mounts

Ahh, there's the crux of it. A tripod is not a mounting device, it's made for holding a camera and not being attached to anything else including the ground (it sits on the ground), but especially not attached to something that's moving. So it turns out it's not the camera or the screw that's the problem - it's the mount. Which is probably why I've had a hard time understanding this discussion. Now it's a different story altogether. Yes, a really cheap tripod is a very bad way to mount a camera in a car. They aren't made for that. And, yes, I have failed cars in tech for doing that, at least not adequately securing it enough. If you use a camera mount in the car you will not have any problems or failures. And I don't have to speculate about this because I freaking do this for a living. Did common sense die in the same plane crash as irony?

Frickin' hopeless.

How many times do I have to tell you that cheap ass frickin cameras have had that damn threaded receiver rip right out of the bottom of the camera.

I know you're a camera professional. But in the real world crap has happened. Tripod mounts have failed too. I had one crack. But I'm talking nut ripped out of the bottom of the camera. Its not an argument its a fact. What do you want????


Done.

Gee...ya think I'm gonna get a little extra scrutiny at tech next event?

I'm thinking the white whale itself may need to be tethered.

Kurt Rahn wrote:Gee...ya think I'm gonna get a little extra scrutiny at tech next event?

I will personally direct Mr. Clements to don the rubber gloves and give you a once over.