Mavic Drone Photography – Post-Processing

With all digital cameras, my general practice is to capture RAW images instead of JPEG. Particularly when photographing with DJI Mavic 3 aerial drone, I not only capture RAW but additionally I frequently utilize exposure bracketing and HDR post-processing.

Portland Maine

The image shown here is the result of post-processing with Adobe Photoshop.

Having used the original DJI Mavic Pro, Mavic 2 pro, and Mavic 3, all have exhibited similar difficulty holding fine details in the highlights. This commonly occurs with architectural details under full sun; highlight details are easily lost. My solution is to use exposure bracketing and HDR post-processing; this means the original capture includes the best exposure, then two other exposures, one that is a bit brighter and one that is a bit darker. For the example, the photo here. I expected in advance that the highlights were at risk of getting lost; in retrospect, yes it was true.

The original three exposures are shown below. The best exposure is in the middle. As has been typical of Mavic 1,2, and 3, architectural details in white buildings have not been fully captured. The second problem is that the green trees are too dark. That second problem can be remedied in post-processing without much difficulty. However, if details in the highlights are blown out, recovering this can be difficult or impossible.

Initially, I perform basic adjustments in Adobe Lightroom and then open all three using “Open as layers in Photoshop”. That opens the three separate files as ProPhoto RGB (16-bit color depth) and with the adjustments made in Lightroom. Once opened in Photoshop, select all three layers and choose “Auto-align layers” in case the drone may have moved slightly between exposures. The best exposure I move to the bottom layer. From the other two exposures, I select specific parts of the image and these are overlayed over the bottom layer, effectively replacing problem areas.

Because the darkest exposure has retained all details in the highlights, I select the brightest areas from this exposure. Typically, this can be accomplished with either Photoshop’s built-in “Color range” selection. Once that selection is made, I often need to tweak it a bit, manually deselecting some areas that were selected but I don’t want those areas selected. Then feather the selection and convert it to a layer mask.

Using the brightest exposure, I similarly selected the green trees. That proved to be more difficult and I spent much time tweaking that selection. This selection is also converted to a layer mask. This replaces the overly dark trees in the base layer with a brighter version. Of course, you might use tools such as brightness or tone curve to lighten the trees in the base image, but the underexposed trees are more prone to luminance noise. Leveraging the brighter exposed trees does not suffer from noise, but is a bit more work to achieve.

There are alternative methods. I sometimes use Raya Pro by Jimmy McIntyre.

The final image is a composite assembled from three separate exposures of the same scene. I save this layered file as TIFF, but you can also save it as PSD (Photoshop format). I may merge all layers and export a JPEG file, but I keep the layered file. Commonly, I do return to this file and make further adjustments. For example, I may decide later that one or more of the exposures has noticeable noise or is not sufficiently sharp. The layered file allows me to make adjustments to the individual exposures.

Mavic 3 Photo Quality vs. Mavic 2 Pro

Mavic 3 Photo Quality vs. Mavic 2 Pro

Although the Mavic 3 includes some groundbreaking new features, many reviewers will render their opinions about such things and I will not do so here.  I am only analyzing the photo quality from Mavic 3 with comparison to the predecessor Mavic 2 Pro.

Mavic 3 includes two cameras.  I am comparing the main camera to the camera of Mavic 2 Pro. The Mavic 3 main camera has a fixed-focal-length lens, 4/3 image sensor, and variable aperture.

The Mavic 3 supports capturing photos in either JPEG format or JPEG & RAW. While I almost always capture photos in RAW format and I do not need a JPEG, the initial release of MAVIC 3 will always save a JPEG.  That could possibly change in a future firmware update.

See the end of this post for a link to my 2018 comparison of Mavic 2 Pro image quality, compared to original Mavic Pro.

Testing the Mavic 3 at sunset … f\3.2, ISO 100

The main camera of Mavic 3 uses a 4/3 image sensor; this has implications.

  • The image rectangle has an aspect ratio of 4:3, which is same as Mavic 2 Zoom but is different than Mavic 2 Pro and Mavic Air.  For me personally, this implies that I must crop each image and discard some pixels to obtain a final image of 3:2 aspect ratio.
  • Four-thirds and Micro Four Thirds (MFT) are established standards. The diagonal measure of a 4/3 sensor can vary but is typically around 22mm.  Compare this to Mavic 2 Pro and Mavic Air 2S, which each have image sensors with diagonal measure around 16 mm.
  • A larger sensor can allow for either more pixels or larger pixels.  The Mavic 3 pixel resolution is not significantly different than Mavic 2 Pro.  Likely the individual dot elements (pixels) are larger.  Potentially that might translate to better ability to gather light, potentially reducing the signal-to-noise ratio.  But that is theoretical.  As the old saying goes, the proof is in the pudding. 

Some online articles suggest that the larger image sensor “gives Mavic 3 higher resolution and dynamic range” but …. higher resolution is a dubious claim and higher dynamic range is theoretical.

DJI drones have historically employed Sony Exmore image sensors; DJI/Hasselblad cameras are no exception. I must guess that the Mavic 3 is using the Sony IMX472-AAJK, but I have not confirmed this.  That sensor can capture all 20 megapixels at 120 frames-per-second.  Notably, this sensor uses “stacked CMOS” technology and is the first ever stacked CMOS sensor in the 4/3 size.  This sensor diagonally measures 21.77 mm.

The Mavic 3 user guide (available online) includes this disturbing note: “Before shooting important photos or videos, shoot a few images to test the camera is operating correctly.”   I shudder to imagine what might have happened during initial product testing to warrant such a warning.

Pixel Resolution

If you want a final image to have3:2 aspect ratio, then any 3:4 image must be cropped and that includes Mavic 3. Technically, you end up with fewer pixels than Mavic 2 Pro and Mavic Air 2S.

Mavic Air 2S @ 3:2 aspect  ………………  5472×3648  = 19.9 million pixels
Mavic 2 @ 3:2 aspect  ……………………… 5464×3640 = 19.88 million pixels
Mavic 2 @ 4:3 aspect (crop from 3:2)… 4852×3640
Mavic 2 @ 16:9 aspect (crop)…………… 5464×3070
Mavic 3 @ 4:3 aspect  …………………….. 5280×3956 = 20.88 million pixels
Mavic 3 @ 3:2 aspect (crop from 4:3)… 5280×3520 = 18.58 million pixels
Mavic 3 @ 16:9 aspect (crop)…………….. 5280×2970

Color

Opening RAW images in Adobe lightroom, the color is a bit green. That’s correctable but really annoying; I’m guessing this problem is because Lightroom/Photoshop/CameraRAW do not yet include a camera profile for Mavic 3 (Hasselblad L2D-20c).

Looking at the JPEGs, the color looks good – not vibrant, but good.

Sharpness

Comparing images from Mavic 3 and Mavic 2 Pro, at aperture f\3.5 and f\4.0, the two are equally sharp at center of the lens.  However, away from center, toward the edges of the image, Mavic 3 exhibits improved sharpness over Mavic 2 Pro.

High-magnification crop from the original RAW image

Image noise

Considering all ISO 100 through 3200, Mavic 3 shows less luminance noise than Mavic 2 Pro. However, at any ISO, low light situations can result in considerable chroma noise in both shadows and midtones.  It is worst at IS0 800, 1600, 3200.  While it can usually be mitigated using noise-reduction in post-processing, the 4/3 image sensor should not exhibit this problem.  

As the camera saves both RAW and JPEG, I looked at the JPEGs.  Luminance noise is reasonably mitigated through ISO 1600; mitigation can be dicey at 3200.  Chroma noise is essentially eliminated. However, not surprising, this noise reduction comes at a price –  loss of sharpness.

Luminance noise in shadows … ISO 400, daylight with ND4 filter … N0te: ambient light and altitude are not identical

Mavic 3 … chroma noise in low light … ISO 1600

Chromatic aberration

In some situations with high-contrast fine detail, Mavic 3 can suffer from chromatic aberration similar to the first-generation Mavic Pro.  Although Mavic 2 Pro significantly reduced chromatic aberration, Mavic 3 is a step backward. This is observed with the clear DJI lens cover; I haven’t tried it yet with the naked lens.

Mavic 3 (RAW image) shows improved sharpness, but also shows chromatic aberration in railing balusters

Shadow detail

Considering detail in the darkest shadow areas, Mavic 3 has a slight advantage to reveal details that Mavic 2 Pro cannot. The difference is quite small.

DJI has stated that the Mavic 3 main camera has 12.8 stops of dynamic range, which is not significantly greater than Mavic Air 2S or Mavic 2 Pro.

Highlight detail

Both the original Mavic Pro and the successor Mavic 2 Pro often failed to resolve subtle detail in highlights. This commonly manifests in architectural details that are white,such as clapboard siding and trim mouldings.   Mavic 3 does shows a slight improvement.

Images captured with Mavic 2 Pro – particularly images that include architecture – have commonly required a great deal of effort to safeguard highlight details. At the time of capture, exposure bracketing saves an additional exposure wherein the highlights are rendered with reduced brightness.  In post-processing, that exposure is developed carefully and specifically for hightlight details.  Then those highlights are manually blended into the other exposure.  Only time will tell if Mavic 3 eliminates the need for that extra work.

Remote control

Apart from the camera itself, I must mention the remote control.  With the Mavic 2 Pro, I have very commonly used the camera control dial under the right index finger.  With Mavic 3, the RC-N1 remote controller has no such control dial; exposure settings can only be controlled via touch-screen. The expensive RC Pro controller includes a dial for right index finger, which I vaguely believe controls camera zoom and I do not know if it can be used for exposure purposes.  I did not spend the extra $1000 to get an RC Pro.

Mavic 3 … , daylight with ND4 filter, f\4.0, ISO 400


Here is my investigation of the Mavic 2 Pro, back when that was released in 2018:

Geofencing -The Difficulty of DJI Drones

On multiple occasions, my intended drone flight was defeated because my DJI drone refused to spin-up the propellers.  Although the flight is authorized by the FAA, the drone refuses to launch.  With proper planning, this problem is avoidable.

DJI drones include a safety feature known as Geofencing, which is intended to prevent flying in areas that are could be unsafe, particularly near airports. There are different systems of understanding the airspace and the DJI system is entirely different that the system employed by the FAA. 

Local airport facility grid

Anywhere around controlled airspace, maximum flight altitude is determined a grid layered across a map; each grid-square indicates maximum altitude.  As this is local to the facility/airport, it is commonly referred to as the facility grid. 

A flight plan that does not exceed the stated maximum altitude can often be approved in seconds by a computer, without need for review by a person. This is made possible by a computerize system called LAANC (low altitude authorization). Submit your flight plan via a mobile app that supports LAANC. If you succeed in receiving authorization, you may need to export that information and then submit it to DJI to unlock your drone.

For years, I used a LAANC-enabled app called AirMap. Recently, that failed (and I found some rumors online why that might be true). Ultimately, I was forced to switch to a different LAANC-enabled app and I now use Aloft (https://www.aloft.ai/), formerly known as Kittyhawk.

If your drone is locked and will not launch, flight authorization from the FAA – by itself – does not unlock a DJI drone.

DJI Geofencing

Based upon the current GPS location, the drone automatically is aware of local flight restrictions. Potentially, it can refuse to take off.  In some cases you may be able to unlock it from your flight controller; this is called self-unlocking.  In other cases, self-unlocking is not allowed and you must request unlocking DJI Fly Safe (https://www.dji.com/flysafe). FAA flight authorization is a prerequisite.

In advance of your flight, always check the DJI Fly-Safe geofencing map.  If you’re flight is either fully or partly in a blue zone or red zone, you will need to manually unlock the drone.  DJI GEO system shows approach paths to airport runways and it is these areas that are likely to be considered no-fly zones. DJI did not invent this system; it is based upon LATAS (Low Altitude Traffic and Airspace Safety), which I have read was pioneered by PrecisionHawk.

Do not wait until you arrive at your launch location before checking that your drone will be able to launch.  Research in advance: weather, FAA controlled-airspace restrictions, NOTAMs, and DJI GEO restrictions. 

In specific geographic locations, your drone controller may display “NFZ”, which means “No-fly Zone”. When locked due to a NFZ, the drone can only be unlocked via the DJI Flysafe website; it cannot be unlocked via self-unlocking. 

(I remember a conversation with a police officer in Boston when he asked to check my flight authorization. When I told him the drone would not launch in a specific location, he suggested that the pilot can simply unlock it and I told him that is not always true.  Clearly this guy does not have personal experience flying DJI drones within the class-B airspace of Boston Logan airport.)

On mobile devices (e.g. smartphone), the Fly-Safe website reports that unlocking is not supported on the mobile website.  The solution is to use a full-screen computer.  Do this at home before you drive off to your launch site.

For custom unlocking via the DJI Flysafe web page, you probably need a computer.

Upon submitting your request, two things happen.  You will receive an email that states “Unlock application is created.”  The web site shows you that the request is “Pending review.”

If all goes well, two things will happen.  You will receive a subsequent email  within less than 10 minutes stating “Unlock application is accepted.”  The website shows you that the request is “Accepted.”

Your login username must match: Flysafe web site & the mobile app.

Import the unlock certificate to the aircraft

What happens next is not entirely obvious and requires a bit of care.  You launch the app for piloting (e.g. DJI Go 4 or DJI Fly) and find the menu item “Unlocking License” (DJI Go 4 app) or “Unlock GEO Zone” (DJI Fly app).  The app retrieves any unlocking authorizations via the Internet.  This requires two things.  You must be connected to Internet data (e.g. Wi-Fi or cellular data network).  Whenever you launch the app, you must be logged-in and the username must match the username that you used when requesting the unlock.  (I have once stumbled because I had inadvertently used a different login, the unlocking license could not be found, and my intended flight did not happen until after I solved the mystery.)

If all goes well, your unlocking authorization will be listed.  You’re not quite done yet; there are two more steps to unlock the drone. Though the license is recognized by the remote controls, the license must be copied to the drone.  Look for “Import to Aircraft”.  Do that and the app will then show that the drone has the license and it appears with a on-screen enable/disable switch.  As the default is “disabled”, you must slide it to “enable” before the drone will finally unlock the NFZ. The display on remote controller will change from “NFZ” to “Ready”.

NOTAMs (Notice to AirMen)

Mobile apps that support LAANC will show you both the boundaries of controlled airspace (class-B, class-C, class-D, class-E ground level) and all local facility grids. However, most of these apps do not show active NOTAMs. To see active NOTAMs, simply look at Skyvector.com. Active NOTAMs appear as red circles.

Schooner at Gloucester Harbor

In addition to visiting Gloucester this weekend, I also ported all my photography and tools to a new computer. As I imported new images from a camera drone, I took the new computer on a test drive to verify that my tools were all in good order.

This scene had both very bright highlights and very dark shadows; I doubted that a single exposure could contain both the highlights and shadows. As you likely know, such situations are known as high dynamic range (HDR). I captured a bracket of three exposures. In retrospect, it was a wise choice. The middle exposure was spot on, however the foreground was nearly black and some background highlights were blown out – white boats and white buildings. The darker exposure provided correction for the blown-out highlights. The lightest exposure was used to replace the black foreground water with dark-blue water.

Initially, I processed each of the three in Lightroom and then combined them together using Photoshop. From Lightroom, open the three images using “Edit In” -> “Open As Layers In Photoshop”. Once opened in Photoshop, select all three layers and choose “Edit” -> “Auto-Align layers”. Here, there are six Projection options; I chose “Reposition” because the three images were identical composition that varied only by exposure.

A selection of the highlights was applied as a layer mask on the darkest layer, such that only the highlights are used from that layer. A selection of the foreground dark water was applied as a layer mask to the brightest layer such that the foreground is lightened. The resulting image is shown here on the right.

From there, I applied three image filters by Alien Skin. First was Bokeh, to blur the image – except for the schooner. Then I used two different variations of Snap-Art. All this was done through Photoshop. Upon saving all of this (TIFF file), I was back in Lightroom. Judicious use of brightness, clarity, and color saturation enhanced the simulated brush strokes. The end result is shown here on the left.

One Year After The Fire

One Year After The Fire

October 23, 2018; 10:20 A.M.

Mid-October 2018, I photographed Wakefield Massachusetts using an aerial drone.  As the autumn colors were not well developed yet, I returned a week later to make the same photo again.  That’s the first photo here, October 23, 2018.

Some renovation work was in progress that day. You can see scaffolding against the steeple and one of the tall windows is laying on the grass.

In the evening later that day, a lightning storm passed through the area and this presumably sparked the fire that destroyed the First Baptist Church. The next day, I again put the drone in the air to photograph the aftermath of the fire.

Today is the one-year anniversary of that fire, so I returned to again make the same photograph, but without the church.

October 23, 2019; 10:30 A.M.

Outdoor Photography – chasing mother nature

Outdoor Photography – chasing mother nature

Rumney Marsh photographed with an aerial drone (sUAS)

I first visited Rumney Marsh in the month of May.  Although I discovered some great photo compositions, the marsh was mostly brown.  Presuming that the grasses would fully transform the landscape into a greener palate, I vaguely planned to return some weeks later. Shown here below is my first image from the May visit:

Rumney Marsh in the month of May

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This year, spring in New England has featured more rain than normal. Dry days are a bit like currency – have to spend them judiciously.  Five or six weeks later I returned to the marsh on a dry day and found the green grasses covered the land, as expected. Unexpectedly, coastal clouds were lingering and the water reflected white sky (not blue sky).

Rumney Marsh (June) under cloudy skies

While that is a nice image, … I had imagined the water reflecting a blue sky. So, I returned later that same day after the clouds cleared away. That final image is shown at the top of this article.

In all three instances, the image required post-processing for HDR, particularly because the buildings on the horizon were too bright. So each of these three instances is a combination of multiple exposures, simply to control the dynamic range of light.

Image Quality : Mavic 2 Pro vs. (original) Mavic Pro

Image Quality : Mavic 2 Pro vs. (original) Mavic Pro

Mavic 2 Pro and the original Mavic Pro

 

The day of the new Mavic 2 release one week ago, numerous sites and YouTube channels already had reviews prepared. DJI had judiciously provided new Mavic 2 drones to people who would do these reviews. I have no intention of rehashing that stuff. I am interested specifically in the camera performance.  Because I am largely interested in image quality, we’re talking about the Mavic 2 Pro, not the Mavic 2 Zoom.  As for video quality, we’ll have to leave that for another day.

For high-quality images, DJI now provides this choice: Phantom 4 Pro, Mavic 2 Pro, Inspire 2 with Zenmuse X5s, Inspire 2 with Zenmuse X7.  The unique value proposition of any Mavic is that it folds down to a size that can fit in a camera bag. A Mavic drone and remote controller requires physical space similar to a DSLR camera body and a zoom lens.

For photographers, is the upgrade worth it, from Mavic Pro to Mavic 2 Pro?
Yes, after brief testing this morning, there is no doubt in my mind.

With the advent of Mavic 2 Pro, the camera difference between Mavic and Phantom has been erased. Both the variable aperture (f/2.8 to f/11) and the sensor resolution (5472×3648) are on par with the pre-existing Phantom 4 Pro and superior to the original Mavic Pro.  Note that this is a 2:3 aspect ratio compared to a 3:4 aspect ratio of Mavic Pro, Mavic 2 Zoom, and Zenmuse X5s.

Note that camera is new and not exactly the same as P4P. DJI bought a majority stake in Hasselblad a couple years ago and this apparently is the first fruits of that partnership. (Yes, DJI essentially owns the legendary Hasselblad company.)

According to the numbers, the angle of view is a bit different, though I did not notice during actual use.  Mavic 2 Pro provides a FOV equivalent to 28mm lens on a full-frame camera. This is narrower than the original Mavic Pro’s equivalent 26mm and narrower than the Phantom 4 Pro’s equivalent 24mm. Despite being less wide angle, vertical lines can still keystone strongly and you may choose to correct for that in post processing.

Here are the problems with Mavic Pro that I hope are improved with Mavic 2 Pro.

  • Dynamic range in the Mavic Pro was not very good. In high-contrast scenes, highlights can easily blow out and/or the shadows block up. To mitigate this, I have sometimes captured multiple RAW exposures and then post-processed for HDR.
  • Using RAW capture, if the highlights do not blow out entirely, the camera still fails to resolve details in the highlights. For example, houses with clapboard siding in full sun – the separation of the clapboards may be entirely absent in the image. This seems surprising to me … if the story is true that the RGB color space has finer granularity in the highlight range compared to the shadow range.
  • Image noise, particularly in shadows. To mitigate this, I have relied upon heavy-handed post-processing. While noise reduction in Adobe Lightroom is very good, there is a price to pay – higher levels of noise reduction can deteriorate details throughout the brightness range.
  • With high magnification, images lack sharpness. In post-processing, I have found it necessary to apply twice as much sharpening compared to my hand-held cameras.
  • Color from RAW images is typically worse than any other camera I have used (except perhaps GoPro Hero3) and the images require heavy-handed post-processing. Of course, RAW images from any camera will always require some degree of post-processing.
  • Blue/red chromatic aberrations. I commonly see this around white baluster railings. Lightroom’s ability to mitigate chromatic aberration typically fails to resolve the problem.

In summary, the Mavic 2 Pro does achieve small improvements in all of these problem areas. So let’s look at some actual images from the new Mavic 2 Pro compared to the original Mavic Pro.

Harbor photographed with both drones

In high-contrast situations such as this scene with white boats and white houses, Mavic 2 Pro still has difficulty retaining detail in the highlights, but is not so bad that it requires HDR techniques to overcome it.  It is still necessary to reduce the exposure by 1/3 stop to protect the highlights (this does not jeopardize shadow details) and also apply highlight reduction in post-processing.

[Click on an image to see the full resolution.]
[Images shown here are all RAW and individually post-processed to the very best of my ability using Adobe Lightroom.]

Detail in highlight areas

Image sharpness

Noise reduction is still necessary but far less than with the original Mavic Pro.

Color of RAW images is much better, requires less correction.

Here’s an example (not a particularly good one) that shows Mavic Pro was unable to resolve the balusters and suffered chromatic aberration.  Mavic 2 Pro did not exhibit either of these problems.

Click on the image to see larger version

 

Finally, a few notes that do not regard image capture.

If you’ve ever fumbled with the gimbal clamp on the original Mavic Pro, or worse yet have forgotten to remove the clamp before powering on the drone, rest assured that the new Mavic 2 Pro does provide an improvement. The gimbal clamp is integrated into the protective dome cover – remove the dome necessarily removes the gimbal clamp.  See the photo below showing both the Mavic Pro and the Mavic 2 Pro.

Gimbal clamp

Unlike the original Mavic Pro, the Mavic 2 includes 8GB on-board memory in addition to a micro SD slot. To access this memory from another device, connect a USB cable (included) to the Mavic 2 USB-C port and turn on power to the Mavic 2. (Remember to remove the gimbal clamp before turning on the Mavic.) After having inserted a micro SD card, the DJI GO app prompted whether to use that instead of the on-board memory.  I am assuming that we must select one or the other and automatic switch-over is not supported, but I don’t know that for certain.

The transmission system between the drone and the controller is theoretically the most robust of any DJI product to date. Mavic 2 utilized second generation Occusync 2.0, while the Phantom line has yet to adopt the Occusync transmission system.  Although Occusync 2.0  reportedly can operate at distances up to five miles, I personally have no need of that.  Increased robustness of the signal is welcome, as I have seen unexplainable video signal loss when using the original Mavic Pro.

Mavic Pro Mavic 2 Pro
Diagonal Size
(Not including propellers)
335 mm 354 mm
Obstacle avoidance forward, downward forward, backward,
left, right,
downward, upward
Flight time on single
battery charge
27 min 31 min
Max speed 40 mph 72 kph
Built-in RAM 0 8GB
Cost (first released) $1,000 $1,450
Battery cost $90 $120
Mavic Pro Mavic 2 Pro
Photo ISO range 100-3200 100-6400
Video ISO range 100-1600 100-12800
Lens focal length Equivalent to 26 mm on 35mm full-frame camera Equivalent to 28 mm on 35mm full-frame camera
Lens aperature  f/2.8  f/2.8 – f/11
Max photo resolution 4000×3000 5472×3648
Max video resolution @ 30 fps 4K: 3840×2160 4K: 3840×2160
Max frame rate @ 1080 96 fps 120 fps
Max video bitrate 60 Mbps 100 Mbps
Video compression H.264 H.265
HDR video no yes

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The Latest Drone – DJI Does It Again

The Latest Drone – DJI Does It Again

DJI Mavic Air
DJI photo

January 23, 2018 – DJI officially announced the new Mavic Air, which again raises the bar for ease of use and safety for aerial drones. Having watched the announcement live this morning, here are the essential details I have noted (somewhat filtered according to what I find most interesting). So, for those interested in aerial drones or aerial photo/video with drones, here is what you need to know in 60 seconds.

Physical

  • Half the size of Mavic Pro and 41% lighter
  • Antennas concealed within the landing legs (away from the body)
  • 8GB internal storage + SD card slot
  • USB type C port
  • Controller is pocketable, removable control sticks
  • Available in black, white, or red

Camera

  • 1/2.3″ image sensor (same size as Mavic Pro and Phantom 3 Pro)
  • 4K video
  • 12MP still photos
  • HDR capture mode
  • 360-degree panorama, auto stitching up to 25 images
  • New 3-axis gimbal, improved vibration dampening, better image stabilization

Flight control

  • Intelligent flight modes, including improved auto-tracking moving subject and two new quick-shot modes
  • Controllable with hand gestures (up to 19 feet)
  • Advanced pilot assist can automatically go around obstacles
  • More stable, can withstand wind speeds up to 22 mph
  • Fly Safe geo system – information about airspace restrictions

Pricing

  • $799 complete
  • $999 with accessories (extra battery, extra propellers, carrying case, etc)

Availability

  • Shipping Jan.29, 2018.

(I am guessing that demand will be high for this product and it will take some time for DJI to fulfill all the orders.)

A Flying Camera – DJI Mavic Pro

A Flying Camera – DJI Mavic Pro

If you are a photographer or videographer and you are interested in the Mavic Pro drone primarily as a flying camera, then this article is for you. This is a run-down of camera controls and options, without discussing flight controls.
Documentation included with the Mavic Pro is minimal and help for the DJI Go app is non-existent.

First of all, let’s point out the obvious. The Mavic Pro has unmatched portability; it folds to a size that can fit in a large coat pocket. The gimbal that stabilizes the camera is probably the smallest in the world.

This drone can be flown using using the hand-held controller alone, or in conjunction wtih a smart-phone and the DJI Go app. You do need the Go app for access to numerous configurable options, but after configuring what you need, it is possible to fly with just the controller and no app. During flight, the Go app gives you a live video feed and camera exposure information, but you may not need to interact with the app except maybe to set the focus.

Not all available features shown here.  These are just some features I wish to point out.

The Remote Controller

The hand-held controller includes quite a few camera controls, independent of any smartphone app.

  • Photo trigger (shutter button)
  • Start/stop video recording
  • Camera tilt
  • Exposure compensation
  • Custom button left (e.g. center focus)
  • Custom button right (e.g. AE lock)
  • 5D button – up, down, left, right each has a different meaning that is configurable.
    (For example, zoom in/out. It is a 2x digital zoom; there is no optical zoom.)

DJI GO app

The app shows real-time video and provides in-flight camera exposure information.

  • Real-time image view
  • Exposure histogram
  • Current exposure compensation setting (1/3 ev increments)
  • Over-exposure zebra stripes during video recording
  • Camera: ISO, shutter speed, white balance, remaining SD card number of photos
  • Video: resolution, FPS, remaining SD card recording time

The app provides extensive camera configuration options.

  • auto/manual exposure
  • ISO (100 to 6400)
  • shutter (up to 1/8000)
  • AE lock
  • touch screen for AF spot
  • touch screen for exposure spot

video menu ___

  • NTSC or PAL
  • size&fps (e.g. 720p @ 120fps, 4K @24fps)
  • White balance (auto, sun, cloud, custom, etc)
  • Style (brightness, contrast, tint)
  • Color (none, D-cinelike, D-log, Art, Vivid, etc)

photo menu ___

  • Aspect ratio (4:3, 16:9)
  • Image format (jpeg, raw, jpeg+raw)
  • Photo drive (single shot, AEB-3, AEB-5, HDR, interval)
  • White balance (auto, sun, cloud, custom, etc)
  • Style (sharpness, contrast, saturation)

options menu ___

  • show real-time histogram
  • orientation (portrait/landscape)
  • lock gimbal when capture
  • over exposure warning
  • anti-flicker (50Hz, 60Hz, auto)
  • format SD card

The app alerts you if a firmware update is available. The update can be applied with a simple touch; the download comes via your wi-fi, through the phone, down to the drone. The time to complete the upgrade was more than ten minutes and consumed about 18% of the drone battery charge.

Bearskin Neck
Bearskin Neck

Compare JPEG to RAW
Compare JPEG to RAW

Photo Quality

For photos, you can shoot RAW, JPEG, or RAW+JPEG. Of course, I recommend either RAW or RAW+JPEG.

I shot the photo above (Bearskin Neck, Rockport MA) recently with the Mavic Pro set to record both JPEG and RAW.  The second photo is a 200% crop from the center, comparing the original JPEG to the RAW file processed as I normally would in Adobe Lightroom.  Overall, the JPEG is good.  I think it is a bit green, looking at the short stone wall.  Signs on the buildings are not legible in either case, but the JPEG is slightly worse than RAW.

With only a half dozen flights thus far, I have observed a couple specific image quality problems.  For still photos, the very small image sensor is no match for a larger DSLR or MFT camera.  I have read that the image sensor is Sony Exmore (wikipedia.org/wiki/Exmor), but I cannot confirm that. The maximum resolution is a respectable 12 megapixels, in 4×3 aspect ratio (4000×3000). You can choose to capture 16×9 ratio, but that is a crop down to 9 megapixels (I personally tested that just now; that’s real, not a guess.).

Photos can exhibit some amount of digital image noise at just about any ISO. Images shot during the low-light of dusk, around ISO 1600, exhibit a high amount of chroma noise.  Samples are shown here below.  For stills, Adobe Lightroom has the best noise reduction I know. While the JPEG processing in the Mavic does a reasonably good job of smoothing large areas, there is loss of detail inside the bridge.  The Topaz Denoise plugin for Adobe is similar.  Processing via Lighroom’s built-in noise reduction allows better control and retains better detail inside the bridge.

Coping with low light

Video Quality

In good light, the video quality is probably on par with a GoPro Hero 3 or 4.  Moire problems may occur when scenery includes detailed patterns, but I have not tested this with different capture resolutions.  As with still photos, low light and high ISO exhibits a high amount of chroma noise.   A product called Neat Video can do a good job of mitigating noise.

The video clip of the snowy mill (at the beginning of this article) was captured at 1080 without a problem.  However, on a separate shoot, I did see a problem.   Several people contributing to on-line forums have reported that 1080 does have problems, including a “pastel effect” which seems an apt description of the problem I saw. People experiencing problems at 1080 also report that the problem does not occur at higher 2.7K or 4K resolution. I have switched to shooting 2.7K and subsequently downsample to 1080 in post processing. However, the higher resolution does not support a frame rate faster than 30 fps; and downsampling does require additional compute time.

For video, I’ve been shooting the “None” color profile, modified with sharpness set to -1. Some pros are recommending two of the color profiles, DLOG (very flat) and ART (not as flat). Alternatively, some people have suggested color profile D-Cinelike and then customized to -2, -1, -1 (sharpness, contrast, saturation). All those suggestions create an intentionally flat result that necessitates some post-processing.

A clear plastic dome can optionally be used to protect the camera. Very first time I captured video with the Mavic Pro, I could see glare due to the plastic dome. Since then, I never fly with the dome attached. Potentially, I might use it if there some risk of water or dust in the air, for example, flying near a waterfall.

 

Pre-flight

Each time you fly, here’s the basic pre-flight steps:

1) Unfold the propeller arms and propellers
(Obviously, attach any propellers that you detached for transport/storage.)

2) Remove the camera gimbal clip

3) Optionally, connect your smart-phone to the hand-held controller

4) Turn on the controller and start the DJI Go app

5) Turn the antennae upwards, which is typically a 45-degree angle

6) Turn on the drone

7) To connect your phone with the drone, touch the “Camera” button on the DJI Go app

8) Check the aircraft status information, including available battery charge

9) If this is a different location than previous flight, calibrate the compass

10) Obviously, check your environment for obstacles or hazzards.
Make sure you are not in restricted airspace.

 

DJI includes a plastic clip to secure the camera gimbal when not in use. Always remove this clip BEFORE turning on the drone. If you fail to do so, the app warns of gimbal overload.

Initially, the Go app will display the “Aircraft Status”. Tap the “X” to close this display.

  • Overall status … Latest Firmware
  • IME … normal
  • Compass … normal
  • Motor ESC status … normal
  • Radio Channel Quality … good
  • Flight Mode
  • Remote Controller mode
  • Aircraft battery
  • Remote Controller battery
  • Remaining SD card capacity

 

The Next Phantom Quadcopter Drone – Phantom 3

Last October, I listed Drones for Under $2000.  A week later, DJI announced a new quadcopter drone, Inspire 1, which was notable, but far above the $2000 price point. This week, DJI announced the third incarnation of it’s original Phantom, which now incorporates some features from Inspire but retains the more affordable price tag of the Phantom line.  Here are the broad brush strokes.

Phantom 3 (DJI press release photo)

Phantom 3

  • Improved camera system supports video and stills. Phantom 3 “pro” supports 4K video resolution.
  • 3-axis gimbal, similar to Phanom 2 Vision
  • The new gimbal seems to pan, unlike its predecessor on the Phantom 2 Vision+
  • Digital video downlink sends live video feed to your mobile device on the ground (up to 720p)
  • Downward-facing visual and ultrasonic sensors allow position hold without GPS (indoors), like the Inspire 1
  • Improvements in motors and motor control provide better stability and longer battery life.

Phantom 3 vs Inspire 1

  • Inspire 1 is larger than Phantom and can fly faster
  • Inspire 1 allows unobstructed 360 degree camera rotation – retracting landing struts will not obstruct the view.
  • Inspire 1 supports dual pilot operation.
  • Phantom is theoretically much more durable than Inspire
  • Phantom costs far less than Inspire
  • Phantom provides a slightly longer flight time.

Not to be left behind, 3D Robotics will soon release their new quadcopter, currently known as SOLO.