Aerial photography -- remote wing mount

[Eric Muehling]

Next weekend I plan to do aerial photography with a Canon XH-A1.

I have a few questions. But first I'll explain the camera setup and how I will control the camera.

SETUP
1) I've welded a steel, U-shaped bracket that cradles my XH-A1.
The bracket attaches to the tripod screw, and it straps to the handle.
2) The steel bracket will be attached to the wing struts of a Piper Cub plane. The camera will be 8-feet out on the wing (well beyond the propeller). I'm confident the camera is secure and will be OK in 90 mile-per-hour winds. The pilot has approved the setup.
3) I have a remote control with an 8-foot cable: record/pause/zoom/focus. I will control the camera from inside the cab.
4) I have a portable DVD player with an 8-foot cable. This is my monitor inside the airplane. The camera's LCD will be closed.
5) The front-facing microphone will be covered with a plastic bag and duct taped to prevent damage from force of wind.
6) The plane has four hours of gas. I have an 8-hour battery in the XH-A1.

QUESTIONS
1) Should I use the image stabilizer? I'm leaning towards yes. This is a small airplane (fabric construction). I don't know if the wing vibrates.
2) Should I trust auto-focus, or leave the camera set on infinity? I'm leaning to setting at infinity. If the image is constantly moving, then the camera may have a difficult time acquiring edges to focus on. Right?
3) Shutter speed recommendation? What will look natural? What setting would you use?

Is there anything I'm forgettingg? Helpful suggestions would be appreciated. I only get one shot at this.

[Chris Hurd]

Hi Eric,

1. Yes, you'll want OIS on in this case, to dampen any vibration transmitted through the mount.

2. If the lens is left at full wide focal length, then the AF should suffice. What are you using for a remote control, specifically? The Canon ZR-2000 wired remote controller allows you to remotely toggle between AF and MF, giving you the best of both worlds.

3. Depends on the selected frame rate and how bright the day is, and what kind of look you want. Default shutter speeds are 1/60 in 60i, 1/30 in 30F and 1/48 in 24F. Shoot in Tv (shutter priority) mode and the camcorder will keep the shutter speed locked where you want it and it will find the proper exposure automatically.

[Eric Muehling]

Yes, I have the Canon ZR-2000 wired remote controller.
If the camera goes to 'sleep' during a period of inactivity, then I hope I can wake it up with my ZR-2000. But I haven't tested that yet.

The ground will (hopefully) be at least 100 feet away when filming.
So I'll focus on infinity with a fairly wide-angle lens setting.

As for shutter speed ... I have more experience with still photography.
I wouldn't shoot stills from an airplane at less than 1/125th of a second.
Does the same rule apply to video? Yes, I'll use image stabalization.
I expect mid-day sun and plenty of light. I'll set ND to 1/6, and I'm thinking
about a shutter speed around 1/125 to 1/500. Comments?

[Chris Hurd]

Originally Posted by Eric Muehling

If the camera goes to 'sleep' during a period of inactivity...

Just disable that function.

Menu > Customize > Custom Function > C.Fn1 > Tune > Item 16 (Power Save) > Option 2 (Off) > Apply

[Trevor Bray]

Eric
See Chris's post reply item 3.
SLR Shutter speeds on your camcorder will result in a staccato movement on your movie. Choose your frame rate and stick with default.

Trev

[Bob Hart]

The Piper Cub structure as I recall it is quite "live" in terms of vibration from its 4 cylinder engine at higher power settings but it has been a long while so my recollections may be faulty.

Try to avoid engine RPM settings which co-incide with or phase in and out of multiples or divisors of your camera's selected frame rate This gets a bit complex to calculate with 60fps and 24fps and pull-down and all the permutations and maybe too much fuss about nothing in any event.

Don't ride your pilot on this unless he is exceptionally experienced as he has enough workload to deal with and performance envelopes may be compromised if too much deviation from familiar power settings is involved.

Slightly richer mixture settings may smooth the engine vibration a little but again don't ride the pilot on this for the same safety reasons plus potential for plug fouling.

Structural compliance in the plastic casework of the AI will be a hidden enemy. This can be partially offset by having a generous baseplate to cover as much of the bottom of the camera as possible plus the added security over the handle you have already mentioned.

If it is possible to add tightly wedged dense foam in around the camera body inside of the "U" section and tape it in, this might be worhwhile as it will furthur dampen case compliance and dampen any vibration in the "U" section itself, keep cold air out, conferring some thermal insulation against the possibility of dewing after descent.

Highspeed tape or gaffer tape with the free ends facing downwind wrapped around the foam and frame might also help retain the camera in event of a tripod bolt working loose. Whilst a loosened bolt might not let the camera go, the camera may move about in the airflow and destroy itself otherwise.

Tape over the tape cassette door to prevent airflow into the enclosure and possible dewing when you come down from higher altitudes and colder air temps. Jets of airflow might also interfere with the tape transport.

Finally, the method you use to fasten the "U" section to the airframe. - Is this a clamping device around tubular sections near the wing to strut junction or does it fit to existing bolted fasteners.

Clamping metal-to-metal or metal-to-painted metal may set up surface or crush-deformation stress risers to fail much later down the track. Despite your pilot's assurances, I would be inclined to enquire with a licenced airframe engineer.

It would be a pity to inadvertantly damage one of these delightful aircraft. As I am sure you are already well aware, safety first and everything else is a bonus.

[Brian Drysdale]

I'm assuming you've got FAA or CAA clearance for your mount. You're not allowed to bolt mount anything onto an aircraft without their approval.

[Jim Michael]

Sounds like they're just taking their chances that an incident will not occur. Approval for their installation would be expensive to obtain if they are not using a camera mount with an STC for the aircraft model being used.

[Wade Hanchey]

I hope we get to see some of the footage!

[Bob Grant]

If you want to try deshaking the footage in post a faster shutter speed helps. Without it the motion leaves odd trails behind when the footage is stabilized.

[Peter Ralph]

FAA inspection/approval is required unless this is an experimental aircraft.

You could kill people if this thing shakes loose.

[Matthew Nayman]

You may also want a rain cover to protect from insects and debris. I have had my camera hanging out the sunroof of a car doing 100mph down a runway chasing an aircraft (experimental ornithopter in Toronto) and the lens got Covered in gooshy insects... great footage, though a dragonfly might even crack your lens :P

[Mats Frendahl]

Since US is the land of lawsuits it might be a good idea to secure it well. As to putting up a camera through the sunroof at 100 mph there might be similar considerations. If you did that on the German Autobahn I guess they'd throw you in jail on the spot.

Looking forward to some footage samples.

[Bob Hart]

A locust leg, speared 5mm into your elbow at 130km/h is not a fun accessory to your day either. I guess there was always a reason not to drive on a stinking hot day with the window down, elbow on door for cool breeze rolling past.

[Eric Muehling]

Thanks for all your comments about mounting to the plane:
1) I'm bracketing to the airplane at a location where the pilot usually mounts his snowshoes or rifle. We'll be flying over unpopulated areas.
2) I'm using brackets that do not not crush the plane's tubing.
3) The bolts I'm using are drilled-through and a wire will be threaded through the hole to prevent the nut from coming loose or backing out (this includes the tripod mounting hole).

Great suggestions for dampening the camera even more with foam rubber.
Yes, I'll provide a photo of the camera bracket and footage after the flight. I'll summarize the setup and the precautions taken in one final post.