13th April 2004
Hola,
A DP asked me if there's any ideas I had for shock mounting a HD camera in a car. The problem is the car is in an off road race. Think the Paris-Dakar Rally. The camera would be shooting out the window, the DP needs to be able to operate (most likely off a video tap) and obviously it needs to be as stable as possible. Any experiences or suggestions would be great. The other problem is that it's a HD cam, so I know the back focus is going to be a problem with all the bouncing around, anything else we can do beyond just the support rods for the lens? I know Chapman makes a vibration mount, but I can't find it on their web site.
Please pass on any web bound info you may know of.
Thanks much,
Paul Niccolls
Key Grip/NYC
Paul Niccolls wrote:
>Think the Paris-Dakar Rally. The camera would be shooting out the >window, the DP needs to be able to operate (most likely off a video tap) >and obviously it needs to be as stable as possible.
This is almost too funny. Ever been in a rally car? Not much space, but lots of "G" forces. I *don't think* there is a mount that will handle the forces present in this vehicle, much less allow for an operator to be with the camera and operate in anything that would be called "safe".
Diapers would clearly be a requirement for the operator.
Certainly is an interesting challenge. I'd love to hear what Mark W has to say about this.
Mark Smith
What you probably need is an isolation mount. We discussed this here several years ago, so there may be some info in the archive. It's essentially a platform suspended within a frame. Start with a large square of wood (2x4) or metal. At each corner run a short bungee cord to the centre. In the centre make a board onto which you mount the camera. Yo can also add a rear extension to the frame and run additional bungees to help keep the camera from moving forward/back (z-axis).
If you don't feel like building this or are unclear on it, I know that Visual Products has some for sale with pictures on their website.
Mitch Gross
NYC DP
Mmmmmmm...... rally cars.
You're in deep on this one. On a standard race car mount, you can expect shocks and loads of about 10- 11 g's; I've confirmed this with load cells bolted into test mounts. In a rally car, I would imagine forces similar to those a football player can expect, in the 45-60 g range.
That said, a custom mount is in order, with limited movement. Forget vibration isolators; they're too soft to take a car slamming into a dune at 110mph. Forget hotheads and wheels; if a navigator can barely hang onto a stopwatch and a map, there's no way you can operate the wheels or sticks smoothly. My suggestion…a couple of strong, dampened mounts placed strategically around the car that will hold 2-3 small Hd cam/lense combos. Batteries and accessories get hard mounted inside water/dust proof pelican cases, bolted to the roll cage.
Have the team mechanic weld some 5/8 steel studs around the car, based on preferred camera positions. Grab a set of 5/8 connectors from doggicam or from Seno at Modern studio. (the doggicam ones are fantastic) Your mount kit will include a selection of 5/8 steel tubing and fittings for your camera. Try welding joints when possible, you can grind them off later. Remember...if it is the Dakar you'll have about 1 1/2 hours a day to rig the chassis, probably at 2 am.
I've used 5/8 mounts on 500cc motocross stadium bikes, Snowcross snowmobiles, Niagara river jet boats, Pitts Special and Antropov aerobatic planes and an Austin Martin Vanquish for a Hype Williams music video(Ashanti-"rain on me"). In all of these cases the mount held a 435 or Movicam with a 400 ft load and a primo.
My mounting philosophy is simple; the mount saves the camera at all costs, and must be able to survive my best boy's test, which we ordained the "Give me a sledgehammer and 3 minutes....test."
Patrick Thompson
Key Grip, Toronto
Mitch Gross :
>What you probably need is an isolation mount.
Fellow list members :
Have you ever observed the camera in lets say a Wescam while it was operating from a vehicle at even low speed on a paved road? The camera is 'jukin and 'jivin all over the place and the image is not. The camera itself may be going through vertical displacements of 8 inches and simultaneous pitch and yaw displacements. And this is driving on paved city streets at 13 miles an hour. In other words the camera mount wants to remain in the same place in space because of its combined physical and synthetic mass of the gyros. Everything else attached to the mount, from the base of the mount outward to the vehicle is actually producing the displacements.
Trying to rig an isolation mount inside a vehicle would mean that the camera theoretically would be moving wildly in all the dimensions it was free to move in, probably destroying itself in the confined space of the rally car and harming occupants in the process. Occupants of these vehicles have to be well strapped in otherwise they'd be bouncing into roll cages and hard parts of the vehicle interior. It goes without saying that isn't very much space in the vehicle to begin with.
I think you'd be better off rigging the smallest HD camera on a remote control pan and tilt head solidly mounted to the car chassis. Transmit the signal from the competition vehicle to a chase vehicle were it could be recorded and the camera could be controlled from as well.
Bring four times the amount of gear for one rig so that you have some spares to handle crashes dust storms and what have you, and be prepared to have everything break sort of frequently.
Consider any equipment brought to this endeavour a total write off before the car leaves the starting line. I spent more than a few years racing and there is really no way to put a pretty face on the hardware situation.
No one said it would be easy.
Mark Smith
To the excellent advice from Patrick Thompson and Mark Smith, I would add that you will have to have the camera "hardened".
Standard HD cameras are not really designed for the kind of incredible shock loads that will be encountered in an off-road rally situation.
I'm not aware of any off the shelf HD tape transports that can withstand that type of abuse. You might want to think about up rezing a standard deft lipstick cam or something along those lines.
Brian Heller
IA 600 DP
Brian Heller wrote:
>I'm not aware of any off the shelf HD tape transports that can withstand >that type of abuse. You might want to think about up rezing a standard >deft lipstick cam or something along those lines.
A while back, I rigged an HDWF900 HDCam to the outside of a NASCAR car, looking forward down the side. It lasted half a lap at speed at California Speedway. Just the sound of the un-muffled engine, reflecting off the outside concrete barrier wall of the track, caused the camera's tape transport to stop recording during the first half of the warm up lap a low speed, let along the eyeball-jarring vibration from the rock hard suspension at 170 MPH. The sad part of that was, even though I was viewing the images from inside the car with a monitor, and watching amazing and expensive smashes and crashes that were being choreographed for the benefit of the camera, I had no indication that the camera had stopped recording, until about the 5th lap at speed where the camera died entirely and I lost the image on the monitor.
I'm doing a job in a couple of weeks, shooting an IRL open wheel car on the same track, this time with speeds approaching 200mph. Even though the TV commercial is primarily being shot in Super 35mm, the rig shots are going to be done with a Super-16, Photosonics 1VN camera. Due to the mil-spec instrumentation origin of these cameras, your body, or even the vehicle, will cry "uncle" long before the camera stops making images. With these newly released film stocks from Eastman Kodak, 7212 and 7217, Super-16 will yield absolutely grainless results that are indistinguishable from Super-35, in SD or HD.
http://www.photosonics.com/Rental/1VN.html
If you feel you need the resolution of 35mm for the large cinema screen, use the "big brother" of the 1VN, called the 4ML, also absolutely bullet proof, though larger and heaver.
http://www.photosonics.com/Rental/4ML.html
Sometimes the simplest solutions are best.
Bill Bennett
DoP
Los Angeles, CA, USA
>I'd love to hear what Mark W has
Not much to add - Mark Smith and Patrick Thompson have pretty much covered the issues.
I would split this challenge into three categories
A. A mount that can hold the camera safely
B. A way to operate it
C. A camera that can survive the environment
As to A, offhand, I do not know of an isolation type mount that could handle the combination of low frequency high amplitude stuff.
An undamped spring/bungy/airbag/sort of arrangement will result in a camera ping-ponging wildly around independent of the vehicle but also not smooth with regard to the outside world - think of one of those paddles with a piece of elastic and a rubber ball on it - the car is the paddle.
A hard mount could work, depending on whether or not you could tune the chassis vibrations out of it, but you would get a locked off violent ride from the frame of reference of the car. I agree with Patrick - this is something that you attempt with the team's chassis guy's active participation - if he can weld 5/8" spuds on, the clamps Patrick is talking about have as good a chance of working as anything.
I go about those sorts of mounts a slightly different way, but more of my rigs were built for lightness and absolute security for aerial work or motorcycle work or IMAX work and were correspondingly slower to construct and slower to adjust - as a friend of mine has pointed out, "When what you have in your hand is a hammer, all your problems look like nails."
I tend to build things the way I build them because that's the way I developed to build things that I build. Either approach could be used to build safe secure mounts to hold the camera to the car... you could even use a worm or chain-driven low profile rotator to have a little bit of pan so you could electrically re-frame during a left of the race...though I would not recommend this. I have built hybrid mounts where I have made essentially a hard mount but included an extremely highly compressed piece of open-cell foam between two large aluminium plates to provide a "catastrophic G-load reducer" - used this on some bikes, a stunt go-kart, and a steel-wheel roller-coaster. I don't think it would work here very well, but something could be developed and tested.
B. Operating - other than an electrical pan rotator or tilt rotator, I would say NOPE and that rotator would not be applicable for any camera larger than a few pounds or longer than a foot.
C. I think that the chances of 3 chip HD camera with on-board tape transport surviving in this environment, let alone getting usable pictures out of the lens/chip/electronics combo is pretty slim. I would be thinking small film cameras
Of course, these are observations based on very little information - show us the track, show us the course, let us go for a ride and feel what the accelerations are going to be, etc etc etc...but the main point I would make is that this not something to be undertaken lightly - there are so many different kinds of things that can kick your butt on a job like this, from temp, to dust, to electrical interference from the vehicle's ignition system (no radio spark suppressors on race engines) to dirt on the lens, to lenses trying to snap out of their mounts, to tape transports giving up completely (from the drum getting bounced out of its bearings) I would not try this with any HD video equipment that is expected to be returned to anyone.
The biggest problem is that you can't design the mount and system for the probable conditions - you have to design it for the worst conditions, which include the vehicle rolling over on the camera side or hitting something hard enough to be stopped cold - At that point, you can kiss the camera good-bye, but you need to do what you can to eliminate the chances of the camera or mount's injuring the occupants of the car or of another car. Imagine an HD camera hitting your windshield while you are going down the road at 40 MPH.
The Chapman vibration mount is kinda cool little device - I have never seen anyone actually successfully use it for damping vibrations - but they get used now and again when you want a "shaky cam" because you can bang the camera head and it will bounce around a bit.
In the case of the sorts of vibrations you will encounter here, it would be worse than useless.
This is a major undertaking - it would be really fun to engineer the solutions to these problems in order to get the shots, but it is not something to attempt lightly or without deep pockets
Mark Weingartner
LA based
Paul,
I would recommend using the Ultra Camera Mounts-Hood/Door and More Mount Kit along with our UCM Ultra clamps to grab onto the roll bars. This is a very rugged and stable car mounting kit. I only have two concerns :
1. When I have mounted HD cameras on roller coasters at Universal Studios we had a significant problem with digital break up due to the G-forces involved. The tape was actually lifting off of the heads and when we called Sony they couldn't give us a solution beside.
2. The second is being able to operate the camera. I have been rigging cameras on cars for years and I am unaware of any head that is strong and stable enough to be reliable in a Rally Race environment. A vibration isolator will only enhance and add to the bounciness of the camera. I would suggest a hard mount using our products and simply hope for the best as far as operating I don't think that it's really on option. I would we be glad have our product developer speak to you about how we can possibly help. Just give us a call.
Sincerely,
Shiloh Eck
UCM-Director of Sales and Technical Assistance
www.ultracameramounts.com
Patrick,
If you like doggicams connectors.
Check out www.ultracameramounts.com
I think you will be impressed.
Sincerely,
Shiloh Eck
UCM-Director of Sales and Technical Assistance
So I did a little digging......
Here's a few rigging options to consider.
Use brackets made from engine mounts. They're available from most industrial supply companies perhaps you could try McMaster-Carr in Ohio ... www.mcmaster.com These mounts come in threaded and studded variations, various density rubber and sizes that could allow custom dampening levels, in directional tangents.
High grade 4130 chromoly tubing costs around $4 per linear foot. When built right, it could support the load of a vehicle in a non direct impact, ie in a rollover. Also, chromoly provides an excellent penetration base when welding, something to appease team mechanics when a quick rig is getting torched on.
For a simple pan/tilt try an Airtronics or Futaba R/C controller/receiver combo with a beefed up drive system to a simple head. I built one for a hydroplane race and it survived an impact and a 15min dunking; not to mention that it only cost about $900cdn (insert exchange rate joke here).
Check out Willy's Widgets( best known for their speed wheels and knock-off Fisher R/O) They could probably fab up a sweet little head for next to nothing(respectively) and give you at least an axis or two.
The 16 mm photosonics that Bill Bennett mentioned would be perfect, however, the problem is the dust during the frequent reloads, and with a max run time of 2-3 minutes and no tap, you would be loading every chance you had. The average fuel/service stop is about 7 minutes, every 3 hours, for every 12 hour Dakar stage - www.dakar.com That's not a lot of mag changes.
Finally, give Shelly Ward Enterprises a call. More than anyone, they are the gurus of vehicle mounts.
Give 'er
Patrick Thompson
Key Grip, Toronto
Shiloh wrote:
"If you like doggicams connectors. Check out www.ultracameramounts.com I think you will be impressed."
I'm both familiar and impressed with your products, they've got great versatility. However I do feel however that the doggicam swivel connectors are the best for 5/8 shaft applications. They can be locked in any position, at any angle, and can be added to an existing shaft rig because of the snap apart configuration.
I do like your ball head mount and the mini Dv plate. May I suggest adding an over/under clamp (I'll send you a DXF/IGES CAD drawing) and a couple of unibody-to-5/8 clamps to the car kits, for more advanced rigging.
Patrick Thompson
Key Grip, Toronto
Good advice on the motor mounts.
There is also a company that makes urethane isolation blocks for running pipes in Kindorf suspended situations - I have used them to clamp around tubes for low compliance vibration isolation. Look for Hydro-Zorb somewhere in Michigan. If you were to use these, you would have to design a mount that stays totally captive if the blocks slip.
Per Bill Bennett's post, I still think the weakest link is the HD part...
Mark Weingartner
LA
Mark H. Weingartner wrote :
>Per Bill Bennett's post, I still think the weakest link is the HD part..
One suggestion, get with the racing team because no doubt they have force-sphere accelerometer profiles of the cars at speed.
Picture a sphere with a point at the centre which represents the car at rest. plot vectors from the centre of the sphere out to the surface based on recorded g forces and these are the force vectors for x,y,z axis accelerations combined moment by moment. Race car guys do this stuff so they can speed the development of chassis components and understand what is happening to the vehicle , why it breaks etc. Road race guys use force circle diagrams because they don't have much z axis to consider compared to off road types.
If the race team will share that data with you, then you will really understand what you are up against in terms of forces acting on the camera. My seat of the pants sense of this is don't expect any HD camera to last very long. Besides not being able to record a image to tape, I would expect a zoom lens to cease functioning, but maybe not before it broke the lens mount off the optical block. Maybe on of the HD "block" cameras ?? and you still have to record the image some place.
Oh yeah, when I said before that it would be nice to see pictures of the solution(s) I meant to say before AND after pictures.
Mark Smith
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