Untitled - Eric Cheng

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Can you put a large-sensor camera on a DJI Phantom? Hobbyists have been trying to bolt large cameras onto DJI Phantom quadcopters since it came out. Mostly, the efforts have been fruitless, with flying times of just a few minutes and a lot of risk involved in putting such a heavy payload on a quadcopter not designed for heavy lifting.

I’ve long thought the Ricoh GR compact APS-C camera would be a great camera for aerial photography. The Ricoh GR features a 16.2MP APS-C CMOS sensor and a 18.5mm (28mm-equivalent) lens. It shoots in DNG, and has a built-in intervalometer and 2-stop ND filter. The camera has come down in price since it came out, and is available right now for $639 on Amazon.

The best thing about the Ricoh is that is weighs only 245 grams, including batteries. This is light as a feather, when you’re talking about cameras with such a large sensor in them.

For reference, the GoPro HERO3 is 76 grams with battery installed (no mounts or gimbal), and 163 grams with underwater housing (the HERO3+ uses a lighter underwater housing, and weighs in at 135 grams). Sony announced the A5000 at CES, which they market as being the lightest APS-C interchangeable-lens camera. It weighs 269 grams, including battery. Sony’s 16mm/2.8 lens weighs 67 grams, so we’re talking 336 grams for the body and lens. The Ricoh is nearly 30% lighter, but of course, has a fixed 18.5mm lens. The Canon Rebel SL1, the lightest APS-C SLR, weighs 407 grams without a lens, which definitely puts us in large quadcopter or hexacopter territory.

In terms of field of view, Ricoh offers the GW-2 21mm wide-angle conversion lens, which is $150, and converts the lens to a 21mm-equivalent lens. I’m not sure how much it weighs.

I was excited when DJI announced the Phantom 2 because it has a giant battery for its size (5200 mAh). Combined with its larger, more-efficient propellers, it seemed like a possible platform for flying the Ricoh camera. Mounting the Ricoh to the Phantom 2 is a challenge, and will require some DIY chops. For quick-‘n-dirty testing, I used the GoPro mount from the original Phantom, which I mounted to the quadcopter using a segment of plastic cutting board (see pictures). On the camera side, I used a GoPro tripod mount and ¼"-20 screw segment, which I cut from a rod using a hacksaw. To extend the Phantom’s landing gear, I used chopsticks and zip ties. It’s pretty ugly, but it works.

During the first flight, the Phantom 2 flew for 15 minutes, 20 seconds. It started to auto-land (15% battery) at 15:10, and the battery hit 25% after 13:20 (I set my first warning for 25% instead of 30%). Immediately after the flight, the two front motors were hot to the touch, and the rear motors were warm. My mounted camera makes the quadcopter front heavy, so this makes sense.

I set the camera to Aperture Priority at f/11, which yielded pictures at ISO 100 with shutter speeds ranging from 1/80 to 1/180. This was definitely not fast enough for the application, and most shots are blurry (no brushless gimbal, here!). In the future, I will likely shoot in full daylight at f/10 and ISO 400 to guarantee high shutter speeds. I also need to balance the propellers and build a vibration-isolation mount, which really are required to get sharp results in aerial photography using quadcopters. I’ll likely use the upper damping bracket from the DJI Phantom 2 Vision (available for $3) and use a custom bottom bracket from a design given to me by Keri Wilk of Rotorpixel, who is currently building a great brushless gimbal for the Vision.

The gentWIRE-videoUSB cable is designed to talk to the UC-E6 connector, featuring a video signal for real-time FPV and a remote release interface compatible with RC receivers. I ordered one, but can’t get it to work. I’m in touch with the manufacturer, and will hopefully have it working, soon. I’ll also replace the receiver in the Phantom 2 with a Futaba receiver so I can see voltage telemetry and use the nice spring-loaded control to fire the camera’s shutter. For FPV, I’ll use a Boscam 5.8Ghz transmitter.

Finally, if weight allows, a servo-driven pitch gimbal for flexibility in composition would add a lot to the platform.

If all goes well, this will be a large-sensor flying camera that can easily be crammed into a single case that fits in overhead bin space on an airplane. A few days ago, a United Airlines gate agent asked to see if my Nanuk 940 case fit the carry-on baggage size tester. Luckily, it fit. 🙂