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Night time mapping

Hello Guys ! I have a job to make a night time map of a Moscow city district. Architects need it to understand how they can approve the lighting conditions in this area. Does anyone have this type of experience and what about the quality? I have a DJI P3P. Maybe you attach any of your night time maps ? Thanks in advance.

Nikita Maru

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We have had quite a few people (almost all in Europe for some reason) attempt night time mapping and we are always shocked at how well it turns out. We don't have any public examples that we can share but the regular lighting along the streets and shorter buildings actually turn out pretty well. There isn't a lot of detail in the blocks between the you can see things on the streets and the model turns out OK too.

Elizabeth
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Hello Ryan. So yesterday i had an attempt and i cant say that it came out what i expected it to be) 

So to make you understand what i am trying to do. Here is a plot that i need to make a night map of.

I need to cover only the streets (highlighted in red) unfortunately the application dont give me a way to exclude the unnecessary zone in the centre> so i made a flight plan like this.

Unfortunately i had to cover this huge zones that are unnecessary. This could really work> but when there was a weak signal the drone didnt make any photos. I have already read about this problem (after i came back). I was quite sure that the drone would folow the plan and make photos even when he loses the RC signal.(I think it would be really great feature of the app> i bought this app mostly, because i thought it would work like this.) I was wrong(* 

That is what i got from my night flight 

So i think the camera settings (i switched it to shutter priority 1/200) was my mistake. 

 

 

Please guys help me. Ive been already paid for this job and i just have to do it correct. 

How do i make the optimal flight plan? What should the camera settings and  drone settings be to get the maximum possible quality for night time shots (Dji Phantom 3 Pro) 

Maybe it is better for me to make the photos with the dji Go app manually (making a drone stop for every photo) Covering all the streets needed and then processing them all together in one time ?   Or is it better to make several flight plans and then unite them on your web ? 

I am really looking forward for your help ! 

Thanks

 

Nikita Maru 0 votes
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You definitely want to be using the automatic setting. Mapping at night is going to be a very light starved and dynamic situation and a fixed exposure time is not going to get the job done.

If there isn't enough light there is little you can do about it though. The other night maps that were done were near Paris and in Berlin where there was a lot of street lighting at regular intervals.

The DJI SDK does not currently support a failover mode that defaults to taking regular images. Our app is optimize to create the most accurate data possible and taking images at a fixed interval will result in substandard results.

 

Elizabeth 0 votes
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Well it's good to see a nighttime phogrammetry project isn't something new.

Here's mine! Now that tech support got my Mavic 2E's firmware problems rectified and the aircraft flying with Map Pilot, I need to get serious about flying this mission. The client wants on orthomosaic of this downtown area where they will do a complete overhaul of streetlights. So they want "before and after" images. I would appreciate advice on how high to fly, overlap, and best estimate of number of batteries, and camera settings. The plan is to fly during new moon. Thanks! 

Curt Meyer 0 votes
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Curt: Sounds like a cool project. Nighttime stuff with plenty of street lights actually seems to turn out pretty well as long as you aren't flying too low. Probably at least 60 meters. People do it pretty frequently and I am always surprised how well it works. 

Zane 0 votes
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https://yadi.sk/d/wJW3igp5oY8JDw 

The Best result i got at the hight of 100 meters and i did everything manually. You need your copter to be as stable as it possible at the shot, so, the best way is to do this mapping on a hight 100-higher. And do it with your hands. I was also shooting the situation with lighting by the way. For the project of new park "Zariadie" near Kremlin. This worked well ! The result is on the link !

https://yadi.sk/d/wJW3igp5oY8JDw 

Nikita Maru 0 votes
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One other question:  3D is not of interest for this project, but elsewhere I read that taking a photo before takeoff was recommended to improve the accuracy of elevation in outputs. If we stick to 2D, is there any reason to include an on-the-ground photo in post-processing?

Currently we plan to have the GCS on the roof of the tallest building within the project area.

Curt Meyer 0 votes
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Nikita - thanks for the response; it's great to see results from someone else's work. I had been planning to fly around 60m, or perhaps even a little lower, but from what you have said I may change my mind and fly higher than 60m. Since you manually controlled your camera, I was curious if you hovered at each point that you activated the shutter? Thanks!

Curt Meyer 0 votes
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Yes Curt . The main thing is to hover as stable as you can on every shot, to get the best result. Because the low light shooting needs more shutter speed. I advise you to take some test shots on different altitude and with different shutter speed and iso. Not to waste your time on shooting all the plot with the wrong settings. 

Nikita Maru 0 votes
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So once again. (IN My Case)

The best way to get the night time lightning plan was 

1.Manual control

2.Shooting from a hight 100+

3. Hovering on every shot

4.used PTGUI full version for stitching the  shots.

Nikita Maru 0 votes
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I'll be getting test flights and images during the next couple of nights with a Mavic 2E, but I am looking for an estimate of how many batteries I will need (in case I cannot fly due to winter weather conditions).

MME's Map Pilot app estimates 5 batteries when flying at 70 m (230 feet), but I know my average speed will be drastically lower than 4.3 m/s (9.7 mph) since this is a nighttime mission and each image-capture will take seconds (not fractions of a second). 

Anyone have advice on estimating my battery demand? Thanks 

Curt Meyer 0 votes
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The number of images will likely be the same and but the time to execute each will be longer. You will just have to do some testing. Map Pilot does not support stop to image flights. The minimum speed supported for waypoint flight is 2 m/s. 

It sounds like you will need to expose for longer than that so you might be on your own for just manually flying the path that Map Pilot designs. We have a bunch of people that use it this way.

Zane 0 votes
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Zane,

I wanted to reiterate an earlier question about including a photo taken while the UA is on the ground -- if my home point is on a building rooftop (~10m AGL), should my "ground" photo be taken on the home point, or on the actual surface of the ground? 

Will I have potential processing problems if I do all my battery changes during the mission on the rooftop? 

Curt Meyer 0 votes
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Curt: please ask this in another thread since this is off topic here. 

Zane 0 votes
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