Cinematography Mailing List - CML
    advanced

Tri-image Aerial

I have a request to mount three cameras underneath a helicopter to shoot dynamic, cost effective, multi screen aerials of a country in the Indian subcontinent for corporate presentation on a wide screen. The requested format was BetaCam, (but not necessarily so) I have both time and budget pressures and am wondering if anyone has any previous experience of transportable rigs or mounts which can be shipped there and which might do the job.

I have considered shooting with Cineflex on only one HD 16:9 camera and letter-boxing it to make it look narrower and "wider" but a Canon 4.7mm lens will still only give me 91*. The biggest problem I face actually mounting three cameras under the helicopter is vibration and most of the solutions are very expensive.

Any ideas or cost effective solutions out there guys (and girls)?

Kindest Regards

LAURIE K GILBERT s.o.c.
Motion Picture Director of Photography
HD Cinematographer

L'IMAGE CINEMATOGRAPHY - Based in Asia - Filming the world
www.limage.tv


Laurie Gilbert writes :

>I have a request to mount three cameras underneath a helicopter to >shoot dynamic, cost effective, multi screen aerials of a country in the >Indian subcontinent for corporate presentation on a wide screen

I have done something very similar. We used the Tyler Belly Mount on a Bell Long Ranger with three Betacams on a plate designed to fit the Belly Mount. The standard nose mount will not accommodate the weight, unfortunately the plate has been cannibalised for other jobs since then. However, it wasn't very difficult to make. The difficult part is to level and align the three cameras to each other to make a seamless semi-circle. We used a variation of a "Winter Mount", which is an instrumentation camera mount. They are veryeasy to adjust in roll pitch and yaw, but are not cheap.

>The biggest problem I face actually mounting three cameras under the >helicopter is vibration and most of the solutions are very expensive. >Any ideas or cost effective solutions out there guys (and girls)?

Yes, sort of. The mounting plate we made had a second plate like a roof over the three cameras. It was attached to the bottom plate with eight support arms. Once the Betacams were aligned to each other, they were secured to the top "roof" plate, and then to the eight support arms via the top handles. This eliminated any "intercamera" vibration. We put this rig on roller coasters, camera cars and a couple of other rigs and there was no intercamera vibration.

There was very little vibration transmitted from the helo to the cameras. However as you know, it is very important that the lenses are firmly supported. The new Tyler HD lens supports are terrific and much better than the old foam roller supports, but you'll need three.

I think I may have some Polaroids of the rig kicking around; if you like I might be able to email them to you.

Best of luck,

Brian Heller
IA 600 DP


>I think I may have some Polaroids of the rig kicking around; if you like I >might be able to email them to you

Thank you for that Brian - that would be appreciated. Currently we have no idea what sort of aircraft is on offer, what figure the client has in his budget, which side of the island the Tamil Tigers hold and whether they are taking pot shots at camera-ships...life as per usual then!

Kindest Regards

LAURIE K GILBERT s.o.c.
Motion Picture Director of Photography
HD Cinematographer


Brian Heller writes:

>There was very little vibration transmitted from the helo to the cameras.

It's been my experience that mounting cameras rigidly to vehicles can often be a very good way of eliminating vibration. The only kind of vibration that matters (at any significant distance from your subject, or when using a wide-angle lens) is *angular* vibration. -- linear vibration isn't much of a problem.

I recently had to shoot telephoto from a tripod placed on a large, rectangular wooden table whose legs were just loose enough to allow the tabletop to jiggle about 1/2 inch in all directions. But it was no problem (with or without stabilization turned on) because the jiggle was always parallel to the floor and created no angular motion at all. (Yes, I checked the legs first, and the table was safe to stand on!)

Dan "lucky" Drasin
Producer/DP
Marin County, CA


Hi Laurie

A single camera solution could be to shoot super-35 anamorphic. With the widest possible length you should be able to get quite a wide view that you then pan and scan to what you want. You could also shoot super-16 anamorphic, but I think you'll get less width (and less quality).

Check with your available rental houses what solution they can offer along the above lines, but I know the technique has been used quite successfully for VFX shots requiring a locked camera where a pan is added later.

Good luck

Roger Simonsz
DP/Operator
Paris


Laurie Gilbert writes :

> Thank you for that Brian - that would be appreciated. (polaroids of three >camera rig)

Sounds like an interesting place.

I won't be able to get the Polas out 'till Monday. As Mr. Kreines enjoys pointing out, I have limited computer facilities and faculties.

You might want to check with Tyler about what aircraft the Belly Mount will fit, if you chose to go that route. You'll definitely need high skids for the Belly Mount. If the local authorities will let you, you could probably just lash the whole business to the skids.

Seeing the Polaroids again reminded me that in order to get a seamless image, it was necessary for the outer cameras to shoot past the centre camera, that is, the right camera was shooting the left side of the image and the left camera was shooting the right side. The Betacams were simply too long to fit them any other way.

Brian Heller
IA 600 DP


I've used a fixed tiltable plate (not motorized) on an A star and Twinstar - it is the "multicam" plate which may or may not be on the Tyler website these days. There is also a motorized one that could take the weight and has a pinch down bar to push down on the cameras.

These will not go on Jet Rangers or Long Rangers.

I did this with 3 vista vision cameras, "crossing the streams" as Brian described : Re : lashing to the skids...

I would not recommend it without a lot of testing and a good deal of care - in the case of A Star and twin star skids, they deflect outwards a LOT when the ship's weight is on them...that constitutes the shock absorption of the landing skids...if you mount to the skids, you will want linear bearings on one side to allow for the flex.

In the early 80's, a nameless helicopter operator built a skid-mounted forward looking shelf for us for our Imax camera with which we shot the 4/5 scale Beach Starship prototype and the Voyager (before it had its "round the world" engines. He used linear bearings to handle the flex - that is how I learned about how much flex there was.

Mark Weingartner
LA based


Mark Weingartner writes:

>Re : lashing to the skids - I would not recommend it without a lot of >testing and a good deal of care ...if you mount to the skids, you will want >linear bearings on one >side to allow for the flex.

As usual, Mark has outstanding advice. Linear bearings and a custom mount is indeed an excellent solution, and probably the only way the FAA Inspectors would allow a rig like that to fly in the US these days. However, with the usual provisos, if you're operating in an area where there's a good chance people might be shooting at you, I would say that ramp inspections are the least of your worries, and a low tech approach might be a good, if not the only, solution.

In the days before an FAA approved Tyler Nose Mount existed and before video taps were developed, the "low tech" technique I have used more than once was a 2x12 piece of lumber firmly attached to one skid and lashed to the opposite skid with bungee cord. This took care of the skid spread. Moreover, there was ample room to mount a video camera which gave us a pretty good idea of what we were filming. This was a great improvement over the grease pencil frame lines on the helo windshield a la early Viet Nam Huey rocket sights.

In the later and more advanced 2x12 model, we used a two piece aluminium beam. We landed where we were shooting, attached the "mount", shot the shots, took off the mount put it back inside the ship and went home – with no one the wiser. We found out the hard way that we couldn't fit the 2x12 in the Jet Ranger, so we had to fly with it protruding from the window – so much for inconspicuous. We also used an Akeley head which we motorized in order to pan and tilt from inside. Pilots actually preferred this to the first Tyler nose mount which was a fixed shelf that sat over the nose of the helo in the pilot's line of vision. This early nose mount didn't tilt, so the Akeley was pressed back into service.

I also used the old reliable wooden 2x12 on "GI Jane", but as sort of a retractable mount inside/outside on a Huey. Our Huey was flying formation with the jump ship, so at times we were seen from the ground cameras. When we were clear, we slid the 2x12 out the doorway with a hi-hat and head screwed to it. The AC sat on the other end to hold the 2x12 in place. Yes, it was saftey'd -- and so were we. It worked pretty well.

Safety proviso :

We were operating over a military reservation and over water so that there were no people below us.

Brian Heller
IA 600 DP


Bungee on one side as Brian has used will solve the flex problem - linear bearings was a better solution for longish lens IMAX.

>This was a great improvement over the grease pencil frame lines on >the helo windshield a la early Vietnam Huey rocket sights.

We used gaffers tape inside the windshield so the pilot had something to frame with besides the little monitor

Wood is great stuff, by the way - they build trees out of it, you know. Just like certain audiophile turntables that used hardwood tone arms instead of metal, the 2x12 approach has the potential to damp vibrations that metal would transmit.

My late partner built a belly mount to carry an Arri 2c or a III out of wood. It used U bolts to attach to the front skids right under the belly and had a two by four boom which extended back and attached to the aft skid mount points with ubolts. It was aerodynamically smooth (and adjustable for Jet Rangers or Long Rangers). It had a tilt-adjustable front shelf

It was all bondo'd and sanded until it was all smooth and sexy, coated with a few coats of zinc Chromate primer (as used on aluminium) and then top coated with glossy gray paint/. Wherever the paint was scratched, you would see zinc chromate underneath. No one ever asked what it was made out of.

I do not believe it was ever used over populated areas - only wilderness.
Worked great...

Mark Weingartner
LA based


Mark Weingartner writes:

> It was all bondo'd and sanded until it was all smooth and sexy, coated >with a few coats of zinc Chromate primer (as used on aluminium) and >then top coated with glossy gray paint/.

That's wonderful. If they ask you can just tell them it's composite.

Brian Heller
IA 600 DP


Brian Heller wrote:

> We landed where we were shooting, attached the "mount", shot the >shots, took off the mount put it back inside the ship and went home -- >with no one the wiser.

So much for STLs!

Kreines/Coosada


>A single camera solution could be to shoot super-35 anamorphic. With >the widest possible length you should be able to get quite a wide view >that you then pan and scan to what you want.

I think this is strictly electronic because post has to be done pretty rapidly in Sri Lanka - but the idea is a good one.

Kindest Regards

LAURIE K GILBERT s.o.c.
Motion Picture Director of Photography
HD Cinematographer



Copyright © CML. All rights reserved.