Mapping with the Mavic 2 Pro and DJI Pilot

For some reason DJI decided to not make a profile in DJI Pilot for the Mavic 2 pro even though it works just fine, so here is our guide on how to use the aircraft with that application.

How To Remove the Green Lens Flair in Mavic 3 Videos and Photos

Most people with the Mavic 3 have been there, thinking they got the perfect shot, only to get back to the computer to edit and post the footage, and then see the dreaded green lens flairs on the photo or videos. It really detracts from the image, especially if there isn’t any green in the shot. Here are some examples.

As seen in the image to the right and below the sun there are 2 bright green dots, which are from the Lense flair.

How to remove the lens flare in photos

My method is to use Adobe Photoshop content-aware tool

Step 1, is to select the green dot with the lasso tool

Step 2, is to right-click in the area selected and select content-aware fill

Step 3, is to edit out any objects that could interfere with the aware fill.

Step 4, is to adjust any errors with either more content-aware fills or using the clone stamp tool.

How to remove the lens flare in Videos

This is a bit more complex, and I have only just started using Adobe Aftereffects.

Step 1. Import the clip into your adobe aftereffects timeline

Step 2. Zoom into the dot and create a mask around the green dots, change the mask setting from add to none

Step 3. Right-click the mask and select track mask, move frame by frame, and ensure that the mask stays around the green dots during the entire clip. Then set the mask to subtract

Step 4. Select the window on the navigation bar and ensure that content-aware fill is selected, then select it on the right-side panel. I generally use “object” and an alpha expansion of 5. Then click generate fill layer.

Step 5. Watchback video and make adjustments, these could be changing the mask size adding reference frames, or changing the content-aware fill type and alpha expansion, it is really dependent on the clip you are trying to edit.

Limitations

There are a handful of videos that are really challenging to remove the lens flairs with just the content-aware fill tools, these are generally where the lens flare

1. Crosses over multiple different surfaces

2. Hyperlapse videos with lots of motion

These can be combated by adding more reference frames in the process and editing them like removing a lens flare in the photos section describes.

How to Prevent the Green Dots

The easiest way to have a photo without the lens flare is just to take the image at angles where it does not develop. Looking directly at the sun with the camera is the highest issue for having the lens flare in the imagery. This can be a challenge when filming a sunset or sunrise, which is where the angles come into play.

Our Services

Here is what we are now offering for drone pilots without the Adobe Creative Cloud, we can remove the green dots from either your photos or videos both products are now listed on our website with either editing 5 photos for $25 or editing a 1-minute video for $80

Giveaway

We are giving away a 60-second video edit of lens flare removal for a Mavic 3 video as well as edited photos, one of our new subscribers to our newsletter and to our youtube channel.

Entry is done by subscribing to our newsletter. Entry opens on1/21/2022. Entry closes on 1/31/2022 11:59 Pm EST. Giveaway will be drawn on 2/1/2022, and the winner will be notified within 24 hours. NJH Aerial reserves the right to alter the contest at any time. Void where prohibited.

Door County Winter Drone Footage, & Prints Launch!

Green Bay freezing over quickly became my favorite subject that I have filmed with a drone, the shapes, textures changes and even the motion very interesting.

Photos

Egg Harbor Marina

Cana Island, Baileys Harbor

Door County Ice Push

Murphy Beach Ice Push

Murphy Beach Pier

Update

Also, products are now available on our new products page! Use the code PRINTSLAUNCH2022 to receive 25% off of any order, valid until January 22, 2022!

Next Week’s Blog

We have been editing the DJI Mavic 3 Photos and Videos and have noticed the green lens flares in a lot of them and they detract from the video. We are doing 2 things for this, launching a tutorial on how to use adobe creative software to remove them and offering a service to remove them from photos and video clips. Subscribe to the Newsletter to get notified when that goes live!

2022 Plan & DJI Mavic 3 Firmware Update

Baha’i Temple, Wilmette Illinois

As we begin 2022, I have set forth a few ambitious goals,

1. Fly Every Single Day

2. Continue Weekly Blogs with at least 1 how-to blog each month.

So far Goal 1 is off to a great start. Even with the challenges of flying during a blizzard on the 5th of January. Getting out and filming more has helped me generate more content for my social media and portfolio (Instagram @NJH_Aerial). This will also help enhance reviews and articles for the blog as the more time spent in the field flying the better the information on the topice will be. 2022 will definitely be an interesting year for the various NJH enterprises and there is a lot to come from NJH Aerial and NJH Tech.

During late December the DJI Mavic 3 had a firmware release, that included focus track, master shots, and time-lapse/hyper-lapse features. I used both the master shots and hyper-lapse a lot during this past week of flying, here are some examples of each.

Master shots

To use the master shot feature fly the drone select the target, and climb to your minimum obstacle-clearing altitude. From here run the master shot and the aircraft will fly an automated pattern around the target.

RAW master shot

This is the unedited footage of the house after selecting it in the DJI application as the subject

DJI Automated edit

Hyperlapse

A hyper-lapse is a motion time-lapse, I used these for a variety of flights, but this video was one of the most interesting ones. The main flights that I have used it for are where the sun is rising or setting and the ice on Greenbay is moving

2022 should be a big year for NJH Aerial, and we will have a lot of content to come. Some of the topics expected by the end of the month are, Filming the Freezing of Green Bay, Our Print Store! , Mobile workflow, and Fixing/modifying a drone created 3D model.

To get updates when we post new blogs & a discount code for our prints subscribe to our newsletter

DJI Consumer Drone Mapping Compairson

For this week we will be comparing the DJI Mavic 3, DJI Phantom 4 Pro v2, DJI Mavic 2 Pro, and DJI Mavic Pro in their ability to map a 3d structure.

For this test, all 4 drones were flown at the Tippecanoe County Amphitheater, on an oblique mapping mission. The DJI Mavic 3 was flown manually while all of the other drones were done through an autonomous mission using the Measure Ground control application. The Mavic 3 has not had a software development kit released for it yet so it is unable to fly automated mapping missions.

All aircraft were flown at 300 feet above the ground with 80% overlap and sidelap. Below are the 3d models generated by running each drone’s images through PIX4D.

DJI Mavic Pro Model

Created from 128 Photos

DJI Mavic 2 Pro Model

Created from 112 photos

DJI Phantom 4 Pro V2 Model

Created from 76 Photos

DJI Mavic 3 Model

Created from 145 Photos

Results

The Mavic 3 shows promise and could be a good mapping drone with extended flight times, but without the automated capability, it is being held back. Currently, if I were to go out and buy a drone for mapping it would be the Mavic 2 Pro or the Phantom 4 v2.

For the quality of the photo, the Mavic 2 Pro and the Phantom 4 have the same sensor size 1”, but the Mavic 2 Pro is a Hasselblad, and it looks better in my opinion. The Mavic 3 looks better than the Phantom 4 and the Mavic 3 even though it has the same 20mp file size, the full 4/3rds sensor provides a shaper and clearer photo. Overall, I would rank the Mavic 3 as the number one drone for capturing imagery, but I would rank the Mavic 2 as the top drone for all options right now.

DJI Mavic 3 First Impressions

I recently purchased the new DJI Mavic 3and had the opportunity to fly it around Indiana and Chicago. It has impressed me at every single location with its ability to capture unique images. In the first flight where the wind began to gust to over 40 mph yet, the Mavic stayed still in its position. During a drone class flight lab where we were able to use the zoom to capture images of campus and the airport miles away. There is truly something different about this drone.

My favorite feature from the first week of use has to be the redesigned aircraft cover, gone is the finicky plastic dome around the gimbal. The new cover is a quickly attachable protector that not only secures the gimbal but also secures the propellers in place. This redesigned cover also ensures that the obstacle avoidance, optical flow, and lidar sensors are protected as well. The new cover also allows for the aircraft to be set up and ready to shoot quickly with the props remaining on the aircraft in storage.

My other favorite feature is the zoom camera, I really haven’t been a fan of zoom cameras on drones. The ability to zoom in and grab the right shot with the Mavic 3 is fantastic, I usually find myself using around 7x or 14x zoom otherwise the shot ends up too soft at the 28 times zoom. Here are a few examples of what I have done with the zoom feature.

Now for items that could be improved, DJI Fly. The app feels unfinished to me. For example, it only shows the battery percentage and does not allow for the battery voltage to be displayed. I think the redesign menus and simplification have really hurt the application experience. The original DJI Go and DJI Go 4 feel much more complete and customizable in the settings that the user can change.

The standard controller for the Mavic 3, coming from a DJI Inspire 1 and DJI M600 focused pilot, I loved the screen being on top of the controller. This makes the most sense to me as a pilot because you can quickly glance down at the screen without looking across the controller then back up to the drone. I never liked how the Mavic 2’s remote worked with the phone being in the bottom. That’s where the love ends with this controller, the rest feels like they tried to get away with as few buttons and controls as possible. The lack of control for aperture/iso is really inconvenient when flying, and I miss the c1/c2 buttons as I use those all the time when flying any other DJI aircraft. The lack of features on the standard controller feels like an attempt from DJI to upsell most advanced users to the DJI Procontroller.

Below are a variety of photos I have taken with the Mavic 3, they all turned out really well. The second photo received over 300 upvotes in the R/Purdue Reddit!

To summarize although the Mavic 3 feels a little unfinished without SDK and the intelligent features missing until January at the earliest, I am still happy with my purchase.

Next Fridays' blog, 12/10/2021 will be a comparison between the Phantom 4 Pro V2, Mavic 3, Mavic 2, and Mavic Pro when used for mapping with PIX4D. Subscribe to get notified about our weekly blogs

Thrust Reversing Setup on the Anaconda Platform

To begin here is a quick demo of the thrust reversing in action so you can see the uses for it.

What does the thrust reversing solve you might ask?

Well, I was having an issue with the aircraft remaining on the runway during landing as it would roll off the end of the 200’ runway every time. I had a few options for slowing down then aircraft, they were adding servo or magnetic breaks to the landing gear, adding a drag parachute to deploy upon touchdown, or setting up some kind of arrestor hook system, and the thrust reversing. After looking at each option I weighed the benefits and drawbacks. Breaks would help with takeoff and landing as you could set them then throttle up and release them to get an accelerated takeoff. The drawback of the breaks is weight and more electronic systems running, so I looked at the other options. The parachute idea is neat, but based on my experience with the c-astral Bramor platform the complexity of a parachute system usually outweighs the benefits. And for the arrestor hook, it would be lightweight and would help slow down the aircraft in a shorter distance than the rest of the options, but it would take time to set up every time prior to flight.

For all the drawbacks to the other options, the reverse thrust was the only logical solution. This could be done with the Tekko32 F3 Metal ESC (65A) I had in the aircraft after flashing the latest BLheli 32 and changing the settings.

The results of adding the thrust reversing were slowing down the landing distance from 225’ feet to 150 feet. The data from the flight controller shows this.

From the image above you can see the one U-turn that is off the right end of the runway, that was from a landing without reversing the thrust, the 2 U-turns right of the circle are from reverse thrust landings. Below is a side-by-side video of the landings.

So how does one go about adding reversing to an ESC? Well, I used BLHeli 32 Suite, which can be downloaded from BLHeli/BLHeli_32 ARM at master · bitdump/BLHeli · GitHub. I attempted to follow the Ardupilot pass-through for BLHeli, but I didn’t have any luck with it being able to read the ESC settings, it could still control the ESC through. So I wired up a servo extension lead to a spare flight controller I had and put the latest betaflight on the FC. Then the pass-through to BLheli worked flawlessly. The most important change is the motor direction setting, as you want to change it from Normal to Bidirectional Soft. That adds the 3D ability to the ESC, allowing the motor to spin in either direction. Then I changed the center throttle to 1100 from 1500 so I have higher resolution in normal flight as I don’t need high resolution in the reverse/beta range. The seting that I used in BLHeli is below.

Once the BLHeli is set up there are a few changes to be made in pixhawk cube to enable reversing. They can be made by following the ARDUPilots guide here Reverse Thrust Setup — Plane documentation (ardupilot.org) I set it up on stabilized mode with the momentary switch on my Radiomaster T16 acting as the trigger to switch the throttle from normal operation to reverse operation.

I did some further testing and after 4 takeoffs and reverse landings the ESC overheated and shut down, so I will be working on a cooling system for it as well as installing a better capacitor to help filter out the noise from switching the motor direction. Up next for the Anaconda is more autolanding, and this is a step forward towards precise autolandings for the platform. Hopefully, this was able to help you with setting up reversing on your fixed-wing uas, any feedback is appreciated

- Nicholas

An Ode to the Tricopter: The diversion of software and hardware.

Tricopters are a rare sight in 2021, they are as scarce as commercial flights are. This is because they are inferior in flight to quadcopters and other multirotors. It was not always this way though, as the tricopter used to be the premier drone for capturing aerial footage. The main issue with quadcopters is that they could not yaw quickly, this was due to a multitude of factors, but most of them were software-based.

This was the first tricopter that I built at age 10, as can be seen, it was an extreme fire hazard held together by tape, hot glue, and zip ties.

Quadcopters’ software problems were stifling their performance. A quadcopter yaws or turns about its Z-axis but changing the torque applied by the props, this is done by spinning up opposite sides of the drone’s motors and decreasing the other two. This change in torque applied rotates the drone.

Originally yaw on quadcopters was sluggish or would change the drone’s altitude drastically, this was due to software limitations on the flight controllers (FC), and electronic speed controllers (ESCs). The flight controllers could not compensate for other factors while yawing as there were not enough tuning parameters, the introduction of the Yaw-specific parameters allowed the aircraft to become more stable. It still could not yaw quickly, as the ESCs could not respond quickly enough. The original ESC’s used on multirotors were only capable of performing at a relatively slow rate. Then multishot firmware came out and began to increase the responsiveness of the motors. Both software solutions proved to be the effective way forward for multirotors.

What about tricopters? Well, this was the hardware approach, instead of fighting the escs and flight controllers for quicker response times, they go about vectoring the thrust of the rear motor with a servo to yaw. This was initially superior to quads when the ESC and FC response was slow, as vectoring the thrust gave a direct force that could push the tail about without decreasing and increasing the throttle significantly. This hardware-based solution made the best of what was available at the time, but it was quickly passed up and even suffered from faster software being developed. The improved speeds of modern ESC’s have worsened the tricopters ability, as there a distinct yaw wiggle, as the servo tilting the tail motor cannot respond to the flight controller fast enough. This is really challenging to tune out, and most of the time that it is tuned out, the tricopter feels lose and the tail can skid about.

A modern quad is a superior aircraft, but is there still a place for tricopters? There are still a few unique situations that a tricopter is better suited for. One of these is endurance, as an RCexplorer LR tricopter can fly for over an hour, as they are more efficient than quadcopters. With 3 motors, and one servo you can fit larger props and lower kV motors in the same frame base as a quadcopter. Tricopters also are generally quieter than quads as the motors are not fighting each other as much like a quad when yawing. While tricopters are currently down in the fight for the superior multirotor, I wouldn’t count them out yet.

A Bit About Me

Hi, fellow drone & tech enthusiast. Let me introduce myself, my name is Nicholas Hansen, I have been messing around with drones since 2010. Since then, I have started studying drones at Purdue University in 2018 and have worked as a Part 107 drone operator for a variety of fields of work. That happened to be literal fields working for precision agriculture operations flying DJI M600s last summer. I also began working on my private pilot’s certificate in a Cessna 172, and hope to finish up by my graduation from Purdue. I do not just focus on the commercial aspect of drones though, I am thoroughly invested in drone racing, specifically fixed wing racing. My current focus is developing drones and looking for that edge, whether it is a faster racing wing, a VTOL that is lighter and can fly longer, or if it is an RC airplane with a custom brake kit to take off and land shorter than before, you will see it here. Thanks for joining me on this journey, let’s see your designs in the skies!

Me after my first solo, photo take at Lafayette Airport, Solo flight was at White County airport