Are LEDs visible at 3km?

Questions & Answers
1

Having trouble seeing my Mini 2 SE in daylight at more than about 50m, and am thinking about attaching some LED lighting. The ones I am looking at on Amazon are 4 in a pack and 0.6g each, so even with all 4 on the drone I will be under 250g, and they can be attached by gluepad/velcro or rubber strap. The 'zon blurb claims they are visible up to 3km.

I’m fairly certain this will solve my problem in poor light and at night, but paradoxically in bright daylight I suspect I’m still going to be in trouble seeing the drone at any sort of distance, even silhouetted against the sky. My problem is a familiar one, trying to quickly locate the drone by VLOS when I’ve glanced at the fpv screen I am coming to the conclusion that the only way I’ll be able to fly reasonably safely is to rely on the fpv and the map and supplement that with VLOS. Things can happen fast when you’re flying and time spent looking for the exact location of the drone, and even then not being guaranteed to see it, cannot really be afforded.

I’ve been practicing by watching pigeons. They fly over on their way back to roost in the evenings in fairly straight lines, and are not much bulkier than my drone, so seem like a fair comparison. The game is to keep eyes on them until they are too small in my fov to be seen, and estimate how far away that is. 70 or 80m seems typical, less if you are looking ‘into the light’ and having to cope with glare. Not encouraging; I have eyes on the birds and do not have to locate them like I do the drone.

I am not sure a skin would help, though it’s worth trying; dayglo orange would be the way to go I think. It’s probably academic against the light in silhouette anyway. How much difference do LEDs make in full daylight. Are they visible at all at the sorts of distances I’ve been talking about?

Pretty certain Cree strobes would take me over the 250g. I’ve been experimenting earlier with a bicycle LED headlight but have not found a reasonably secure way of fixing it and in any case I’m fairly certain it weighs more than 4g, though haven’t confirmed this.

2

The Strobon Cree standalone LED from Flytron can be seen from quite a distance in daylight. I couldn’t possibly comment on exactly how far though :wink: But Windswept Robert done a test at night and managed over 8000ft. And remember you can get a discount as a GADC member. As for mounting them? You can go with Dual Lock Fasteners, ask over in our 3D printing section where we have some great guys that may be able to make some clips for the legs, or contact one of our members @ash2020 who also sells them on ebay. Not sure if he is still doing them, but they’re great!!! I have both rear facing and downward facing, I find the downward facing ones more useful.
As for skins, you said in a different post you didn’t think they would make any difference. You’ll just have to trust me that the dayglo orange on my mini 2 really helps me. But I fly out in the open where there are a lot of hills that are green in the summer, and brown the rest of the time. The orange really stands out against these backgrounds, but also the grey skies I mostly encounter.
Once you have some more flying time under your belt, you will automatically be able to locate your drone after taking the eyes away. Your brain will start associating landmarks with the drones location, so just get more flying time in and try to stop overthinking, it will get easier with time!

5 Likes
3

These are the best and made for drones.

Don’t waste your cash with the Amazon stuff

2 Likes
4

Thanks Darren, yeah, still sell a few, although I’m not bang up to date with the models. It used to take about a day to do a design from scratch and probably 3 or 4 iterations to get the fit just right. You have to sell a lot of clips at £3 profit to make that back. Nice as a hobby but not as a business. Cheers.

1 Like
7

I did try Strobon Cree for awhile, yes they were good but to be honest, I was one of those who wasted their cash on Amazon stuff and actually found it much better.

3 Likes
8

Strobon Cree looks good; 4g takes me right up to the weight limit, but not over, so I’d only be able to fit one. How directional is it, I mean does the drone have to be pretty much directly overhead (with it mounted underneath) or is it clearly visible at a stand-off angle?

The Amazon cheapo 4-in-a-pack leds would give greater colour and positioning flexibility, but I think I need to go for cree brightness here. Order going in next pension day (Wednesday). Also for prop clamps; how annoying are they flippyflopping about when you’re trying to pack the drone away, can’t be doing with it!

1 Like
9

The one I purchased via Amazon I found gave me a greater visual of the drone at a distance at night than the Strobon LED. That’s just me though, the Strobon might work better for others. I’m not knocking Strobon at all but I just found the other suited me much better.

10

If you’re going 3km the couple of grams is the least of your worries ;o)

10 Likes
11
2 Likes
12

Not so much night flying or 3km, the topic title is a bit misleading. I submitted it under ‘LED astray’, but the mods put it up as a question ‘Are LEDs visible at 3km’, which I quoted as the distance the Amazonian lights claimed to be visible from. My big problem is seeing the drone in daylight and I am sure any light would be an improvement in poor lighting or dusk, relevant as I intend to do quite a bit of golden hour stuff, but I’m concerned that a light might not be immedieately visible in bright daylight.

We are talking about what is apparently a common issue, looking for the drone in the sky after glancing at the fpv.; I know roughly where it oughta be, but if it’s more than about 70m away I have trouble picking it up. If I engage RTH, Mr.Drone comes home but even then I can hear him before I see him, but this time he’s about 30m away Perhaps I shouldn’t worry and I’m overthinking it; I am within the rules, having VLOS even if I can’t see what I’m looking at.

One gets into semantics about what is Visual Line of Sight. I could argue that I have Visual LOS to the Great Red Spot so long as I can see Jupiter, but I can’t make out the Great Red Spot with my naked eye, even wearing my glasses… If the drone is 100m away, and I can’t see it but I know where it is so I’m actually looking at something I can’t see, that’s not quite ‘eyes on’ but arguably conforms to the CAA requirement, because I can see any obstacloes in it’s vicinity or between me and it.

Had it up to the 120 limit the evening before last, and could just aboutemphasised text** make out a tiny ‘x’ against the blue sky background. It’s visual cross-section is arguably less if there is much horizontal stand-off, and of course if it is below the tress/buildings/hills skyline it disappears altogether anway. My previous cheapo Global Drone P8 had twin headlights that were pretty useful in this situation.

I have an impression that a Cree would be more visible in daylight conditions and still pretty good in dusk/nighttime flying. But I can see why there is a temptation to fly by fpv rather than VLOS; it feels safer whatever the CAA say and if I have an observer with me, he/she’ll have the same problem retaining visual on the drone as I do.

But, if I am reading this correctly, the CAA will be happy for me to glance at the screen for info so long as I keep eyes on the drone, which means being able to locate it immediatedly when I look up from the screen. I’m gonna need a light.

I’ve ordered a Strobon Cree. I’ll see how much spread it’s beam has before choosing a mounting position, but underneath angled a little forward sounds best.

2 Likes
13

It also mentions orientation don’t forget

4 Likes
14

Whaddaya mean Orientation, I’m not gonna be flying it as far as Leyton…

This would have been an advantage of the Amazon lights, red port green starboard, but of course once you start using colours you lose some of the distance visible. I have a 3W Cree torch so I know how bright they are!

1 Like
15

From CAP722

image
image2160×1525 413 KB

6 Likes
16

I don’t see how anyone who asks can you see your drone and it’s orientation can argue if you say yes I can see it and it’s heading that way , if they can’t see it that’s their problem not yours , as long as it’s within a reasonable distance then how can they prove you can’t see it .

1 Like
17

3km :wink:

3 Likes
18

Maybe a tad over reasonable lol

5 Likes
19

Hang on a sec. I never said I wanted to see a drone 3km away, though I did mention that the blurb for the Amazon lights I was looking out claimed that they could be seen at that distance. My heading for the topic was ‘LED astray’ (clever, huh?), which got lost somehow and the site substituted their own, possibly under the influence of an AI reader…

It would be presumably perfectly possible to fly that distance by fpv, so long as there was a direct LOS between the remote controller/smartphone and the drone. My Mini SE can fly at 38kph, at least that’s what the wind resistance specification is, and battery runtime is 30 minutes, so if that means that it can fly 19km, then it could accomplish an out-and-back journey of 9.5km at a push. Let’s say realistically 8km; nobody can see a drone 8km away, no matter how many times they ate up all their carrots like Catseyes Cunningham…

I would argue that provided the height was sufficient to safely clear any obstacles and that visibility was good enough to see any other traffic in the area, this would be perfectly safe. That doesn’t mean I’m going to try it; letting your drone out of your sight requires a huge amount of trust in the positioning and the control signal technology. This technology is astonishingly good, but £250 is a lot of moola to a poor pensioner, and I don’t trust it that much.

The CAA know more about using airspace than I do, and I assume they establish rules for good reasons. I can’t actually see a need to fly more than about 100m from base for my photographic purposes. I’m happy to go up to the 120m limit for a viewpoint, but that’s not the same as flying off into the wide blue yonder.

A lot of it is common sense, and some of it is advice and rules. Nesting birds and migrating flocks on rest stops are well known and easily avoided, and the migrants are not present for much of the year. I live close to the Severn Estuary, and am aware of the feeding migrants, mostly in autumn and winter.

Wildlife in general, if it’s used to human activity, probably mostly ignores drones, as do farm animals, but horses can be pretty easily spooked; I’d avoid them, especially if they have riders on them. The seagulls I was flying amongst on Tuesday evening pretty much took no notice of my drone; it left them alone and they left it alone, but they can be protective of nests and young and I could envisage them mobbing a drone. A common black backed is about four times the size of my drone, and a Greater twice that; don’t think Mr.Drone would come off well in a dogfight…

1 Like
20

I wouldn’t recommend it & you’d also have to have a spotter with you who has eyes ( without using visual aids ie binoculars ) that are as sharp as the Hubble telescope :smile:

21

Yes they all give these distances in a attempt to claim how bright their lights are , so if it can be seen at 3km it must be easy to see at 1km but actually it’s more about where the light is placed and angle between it and you that makes the difference, strobon Cree give guidance on each colour so white gives you the greatest distance and then this decreases through different colours but as I said so much is effected by where it is placed , angle between you and it and the natural light . If the drone is above you then it’s landing light works well if you model has one .
Personally I take VLOS rule less or more seriously depending on where I am flying , so for the most part I fly over farm land in my local area that I know very well but if I am flying in a area I don’t know well I keep it as best as I can in sight , the same as the under 250grms thing as the rule really makes no sense to me although I understand they have to have a cut off point but they are saying at 250grms it’s perfectly safe but at 251grms it’s a lethal killing machine that must be 50 metres away from everything so if I add a couple of the Cree lights to aid visibility if needed I don’t worry as I’ve never seen a plod with a set of calibrated scales in his pocket yet and as I fly in open countryside it’s really not a thing but it’s each to their own . Back to your point though these advertisements on distance are really just a sales pitch as where you place them and the angle between you and the drone and the natural light is more a factor.

1 Like
22

DJI are themselves not immune from using distance as a selling point; my Mini 2 SE claims to be able to pick up LOS signal from the controller and screen date from 4km, far further than the CAA or common sense would have you flying it. You could do it, but I wouldn’t; I lost my first cheapo drone to a flyaway after losing sight of it at about 80m below the treeline, which ‘informs’ my attitude to my £250 pride & joy.

Bright leds are usually powerful but only in one direction and in a fairly narrow beam (I’m familiar with this from bicycle lights). This is the thinking behind some of my questioning about seeing over distance in daylight; I’m fairly confident I can pick out a lit drone against a dark background at probably up to 1km if there are no other lights about if the light is pointing at me.

Nearly all my flying will probably be in highly-popuated areas where there are a lot of other lights, though; sometimes they will be the intended subject of my fliming.! So, as well as the ability to help me locate the drone visually in daylight, the drone light needs to be distinctive enough to stand out against a city centre a mile in the background, or the less dense lights of suburbia, or the floodlights of the big factories along the foreshore. This should be easy enough because I will be able to look for movement that I am controlling, or set to strobe.

I’m ambivalent about strobe, though. Certainly distinctive at range, but bloody annoying close up, and AFAIK there is no remote for them that works at range… The success of the Strobon will depend on the results of flying experiment and experience I’m hoping that the light will do what I want it to on steady or a slow flash, but if not, no biggie, I’ll ‘progress’ to fast flash or strobe if needed. Or learn that diffiernt steady/flash/strobe modes are suited to different conditions; I can imagine strobe being right for bright daylight! Mounting positions is as you say vital, and I need to take note of interference with the filiming. Underneath towards the back seems like a good idea, or on an arm pointing downwards. Much will depend on how wide the beam is.

I agree with your point about the 250g; there has to be a cutoff somewhere. Something like an Inspire or even a Phantom could cause a bit of damage if it dropped out the sky from 400’ or slammed into something/one at full speed! Perhaps the CAA’s thinking is based on that idea, and makes sense in that light, so your point that a 251g is not much more of a killing machine than a 250g is valid, but would be the same at 300, 400g, or more. The drone manufactureres, DJI included, have reacted to the restrictions here and in the US, in the same way as Japanese motorbike manufacturers in the 70s made 250cc models by sleeving the cylinders of otherwise 400cc engines for the UK market, or sleeving 250s to 125s for the later restrictions.

Order is on the way and might be here later today RM 24h Tracked, or Monday, so I’ll soon be able to conduct flying experiments. Got a PL lens and a pair of rotor blade clamps on the way as well.

1 Like