STROBES FOR LONGER RANGE VISIBILITY
Small drones like the MavicPro and Phantom are pretty hard to spot more than 1000ft in anything less than optimum conditions, and the flashing green LEDs are not much help at that distance. . . so adding a high power LED Strobe Light is a way of extending that when it's grey overcast skies or darker backgrounds with trees or deep shadows. I've tried a few and none are really outstanding, so I bought a few high powered flashlights and tore them apart to see if I could do better. First though I just strapped one of them to the side of my Phantom4 and went flying at dusk today. It was just after sunset but not that dark really. Check the video
These things are really bright in your face but at a distance . . no so much.
At 500feet away and 295ft AGL this is what it looked like (VIDEO RIGHT) in the evening sky. Actually it seemed brighter and real life and it certainly stood out, and caught your attention at least but not as bright as expected. I just strapped it on at about 35-40deg down angle and it was on full zoom so I may not have been actually in the center of the beam, but it gives me an idea. Next I'm going to tear it apart and miniaturize it, and take away the lens so it's not a beam just a flasher. I tried that already with this ALL IN ONE strobe (below). Not nearly as bright as this one so I think I really need a 700-800 lumen FLASH that is more like a camera flash to get any good range so next step is to build that and try it after sunset.
Actually, I take it back on this one below. Not great beyond 500-800 feet in bright sky but I took another crack at it this evening and quite visible at a mile . . and still good at 7500ft (~1.4miles) just after sunset. Not easy to follow unless there is a larger reference point, like a tree line a large building or a smoke stack to bring your eyes to the last place you saw it. Definitely, worth while in low-light with a dark or grey cloudy or treed horizon. That's a lot farther than you can normally follow a Phantom in daylight.
Here's another pair of brighter ones (BELOW). I'm going to try next $17 - 12v strobes for motorcycles. I found there is room on the sides of the MavicPro to leave a piece of velcro that these lights can be attached to without causing binding when the arms fold. That should allow good visibility of these flashers from all directions. .
I took Mavic for a spin today with a Strobon tacked to the stern and went off in dull cloudy weather. Against the sky at The video (below RIGHT) shows the Strobon is actually pretty good are helping keep track of a small drone during daylight at a distance of 1157ft.
The exposure in this video is a bit ropey as the camera man struggled to keep track of the disappearing strobing Mavic. It was 4deg C and about 20 mph wind. Pretty cold for his bare hands so not so steady on the camera.
Visually it was a somewhat easier to follow against the darker buildings in the background. See if you can keep track of the flash throught the entire sequence. It's there! Zoom to full screen for the best chance of seeing it moving. Try not to get distracted by the birds.
I don't think anything <700-1000 lumens will not do much in daylight but certainly should help at night or at least 30 min after sunset.
Above is 355 lumin strobing flashlight at 500ft distance and 295ft above the water
On the LEFT here is "STROBON", a $29CDN all-in-one strobe, battery with a flasher/charging circuit. It works fine, but in daylight no more useful than a black silhouette, at helping you keep track of your drone in a bright sky background.
Also I just flew my new Mavic (2nd flight, just got it yesterday) under exact same conditions and it's green forward flashers are not that easy to spot at 1000ft. If it's facing away from you the the RED LEDs on the back show more than twice that far at 2600 feet. . but barely. Still that's pretty good.
I bought this really expensive ($100) 10w Strobe from Larson Electronics (below) with a pretty sophisticated flash controller. If I strip out all the excess packaging and shorten all the wires I should be what I want during normal daylight and probably go 2miles + in low light/sunset,. We'll see. Will post that in a few days . . soon as I get it.
Got and tested the Larson stobe today. Definitely bright and versatile strobe patterns but too big for Mavic or Phantom really so it's probably going back. Also it's just not possible to easily shorten wires or strip away the excess packaging enough to further minaturize it like the pair on the LEFT ABOVE or the tiny STROBON. . . STROBON WINS! . . it's not as powerful as Larson's but virtually as good as the bulkier pair on the right, so I think that Strobon's the ticket. I can stick one on the rear leg of the Mavic with velcro when needed . . the velcro does not interfere with folding the arm at all. For greater coverage I can put a second one on the other rear arm . . .The Dec 2 VIDEO BELOW shows it quite visible at 1152ft especially against a dark background. It should be double that in the dark. No weight and balance issues and no interfering with the camera even in low light.