Instead of a sunset here is a Turkey Vulture who had enough of me tonight:
360 degree panorama of the End of the Ash River Trail: (click on it for a larger image)
If you have been following me at all concerning my adventures into multi-rotor platforms for photography you may already know that I was pursuing a rock steady stable platform from which to take aerial photography shots from. Videography is definitely a back burner issue with me, my main interest is with still photography.
My initial disappointment was with the DJI Phantom 2 Vision in that the camera was rather poor quality, at least when measured against professional photographic equipment. The dynamic range was low, the lens was too wide an angle, the fisheye aspects were unacceptable, and worse the images from this camera were difficult at best to correct for image distortion.
I almost immediately sought out alternatives, the Go-Pro was also unacceptable to me since it also has a pronounced fisheye look to its images. Initially I adapted my Nikon J1 camera to the Phantom but found that it was simply too heavy to be safely flown with the Phantom. After exploring other avenues I found that I would have to spend over five grand to get a decent platform that could safely lift my Nikon J1, let alone my intended camera, my Nikon D800.
I was searching for a cost friendly alternative so I first built a quad using DJI’s E800 motor/ESC combination but found that these motors don’t come close to their advertised thrust in their “Tuned Propulsion System” it should, in all honesty, be called the Detuned Propulsion System. So I set out to build my hexacopter.
I was having troubles tuning the necessary vibration isolators to prevent the inevitable resolution robbing vibrations away from the camera. I was even looking to scrap my drone program entirely in favor of a balloon based system which has very little or no vibrations at all.
Then it dawned on me after a test flight. I have used tie cord as a safety backup in case the vibration isolators would become separated from the camera platform and after a previous hard landing all four indeed became detached. The next flight I forgot to reattach the isolators so the platform was hanging by the tie cord loops. The four tie cord loops were not all equal in length so the camera was flown at a ten degree, or so, tilt angle. After landing and giving my self a Homer Simpson DUH! I decided to download the flashcard and see what I got.
To my surprise the sharpest images that I have taken to this day from any aerial platform! That was the key! For the first time I was able to stitch a decent ten image panorama together! The problem with fisheye lenses is that they don’t stitch into decent quality images very well. Even though the camera was tilted and the copter wavered around due to both the normal GPS wondering and well as the ten to twenty MPH gusty breezes my stitching program, PtGui Pro, was able to easily stitch the ten images together. The other main problem with this particular panorama is that I did not take the images with enough overlap. While there are some areas of the image that certainly need improvement it is the IMAGE RESOLUTION that beats all previous images taken from any ariel platform, at least by myself!
Next to stabilize it even more I will be looking into a downward facing stabilization camera to supplement the GPS for position hold as well as an ultrasonic range finder to supplement the altitude hold function. Using vibration isolators between the camera platform and then suspending the gimbal from the airframe with tie cord is a perfect answer for total vibration isolation for still imagery, while this is obviously not a very good solution for videography – well I really don’t care that much about moving pictures anyway 😉
Update: I may have spoken too soon when suggesting that tie cord may not work for video, here is a video taken with the exact same setup as was used for my stitched pano:
You can clearly see the difficulties in taking a series of still images to stitch together for a pano, the copter is flailing around in the wind. Most of the jitteriness seen in the above video would be minimized when a two axis stabilizing gimbal is utilized. Note that the video from the Nikon J1 is not very good to begin with, compared to the D800, slow panning on a stationary tripod results in marked loss of resolution, not seen at all in this video. I am becoming convinced that a third axis gimbal motor may be necessary due to the unreliably unstable rotation control of the hexacopter is around the z-axis, especially when windy. Yup, retractable landing gear and a third axis gimbal motor may ultimately be necessary.
Well here it is, my first incarnation prototype for a HexCopter. I have to say that a hex handles so much nicer than a quad, much more stable and predictable. This version weighs about 11 lb. (5 kg) or about 830 g/motor or just 30 g above DJI’s recommended 800 g/motor. The total maximum flight time, with an 10,000 mAh battery, was just under 20 min. with the final battery voltage of 21.35 Volts. The DJI ESC’s started giving yellow LED signals with a rapid loss of altitude afterwords. Using a Return To Launch (RTL) voltage of 22.2V should give ample reserve RTL time for a useful flight time of about fifteen minutes. Update: My battery charger reported that it took 10,325 mAh to recharge the battery.
There are several areas where weight can be shaved to allow for the additional weight for my Nikon D800. I am still fine tuning the vibration isolators for my Nikon J1 camera, there is no gimbal motors used at this time. If you look closely at the video the Nikon J1 is having severe problems with the autofocus, I’m probably going to have to give up and simply set the focus manually to infinity, as well as resort to using manual or aperture exposure modes, and forget about 360 degree pano shots, especially near sunrise or sunsets.
I’m not yet sure if I need to reduce the number of isolators, I’m currently using six DJI phantom isolators. I bought isolators for DJI larger gimbals but I found that these were way too stiff for the Nikon J1, although those are probably the ones I will need to use for my D800.
For all of those paranoid morons who are chomping at the bit to shoot down a drone I added an example of just how close a typical drone used by an amateur photographer would have to be to get any meaningful images. All of you dipsticks should realize that only a multi-million dollar military grade drone will be able to count the pimples on your nude sunbathing girlfriend/wives butt-cheeks, and from an altitude higher than you will ever be able to see or hear it from, let alone, shoot it down from 😉
Many have criticized my image called Badlands Sunrise, taken just west of the Yellow Mounds viewpoint area, claiming that they had been there and it did not look like this. Asserting that I grossly over processed the image. I have to say no, the image was not over processed. This last trip I decided to do an actual color corrected image using a color correction card during a basically overcast sky at sunrise.
This is important because an overcast sky is basically natures gigantic light box giving very nearly uniform light with very few shadows. Taking the image at sunrise brings out a very important feature of the Badlands areas, that is that during the daytime lighting conditions, when most people simply drive through the park, the subtleties of color and texture are simply washed out by being overly lighted resulting in being overly bright and thus appearing washed out and bland.
I’ll bet that most of those still critical of my image simply have never experienced a spectacular sunrise or sunset in this park, too bad that they missed out on one of the most spectacular features of this park. Even this unspectacular overcast sunrise is still breathtaking in its overbearing subtitles that are simply lost nearly any other time of day.
Clearly you can see why this area is called Yellow Mounds, Just below the red layer the soil is yellow colored from the fossilized rain forrest and jungle compounds that existed during the era of the dinosaurs. In other words the colors are indeed already there, though very difficult to see during normal daylight.
My Badlands Sunrise image, that will be published by National Geographic this October, had some very unusual conditions that makes it rather rare, there were large areas of grass fires to the east in SW Minnesota, Iowa, eastern Dakotas and Kansas that gave an unusually reddish color to the sunrise. This brought out and enhanced the reddish compounds in the soil, while the yellow nature of any sunrise or sunset colorized the rest. Serendipitously very lucky on my part, right place, right time, incredible scene, awesome image.
While in the Badlands I was waiting for the next sunset I decided to get some close-ups of some prairie dogs using my 800mm lens setup. Unfortunately by sitting behind my tripod on my lens case I seemed to have frightened them and they never really popped out of their closest holes. They were chattering at me only from afar.
After about a half hour I looked over my shoulder and HOLY CRAP! A bull bison was crossing the road about ten feet away looking directly at me! I froze, I didn’t want to startle it so I very slowly moved around to the other side of my tripod, my heart was pounding violently! I was way too close so I had to remove my 2x teleconverter to reduce the lens focal length to 400mm and wallah!. Right in from of me he started kicking up a prairie dog mound and rolled in the dirt, it was so damn cool. He then slowly grazed his way away from me.
I was in the Badlands investigating some copyright infringements. I normally always use a visually non detectable Digimarc copyright watermarking, but I am now convinced that in addition to this, a very noticeable copyright watermark notice needs to also be included to address those idiot thieves who actually claim ignorance or stupidity.
I have eyed this spot for several years and it looked as if this trip was also going to be a complete bust for this site. The sky was almost a completely cloudless blue, forgoing a very boring sunset. BUT there was a layer of haze near the horizon as well as a few clouds that actually mucked things up by filtering most of the light from “lighting up” the ridge-line.
The unique thing that I love about the Badlands is that the formations are basically blank slates, or whitewashed canvases. That is that the formations generally take on the unique colors of every sunset or sunrise. Here a half hour before or after sunrises or sunsets generally makes the entire region washed out blandness and a whole lot of nothing, artistically speaking.
There was a hole, or a layer, in the cloud formation near the horizon while the Sun was about one minute from dropping below that horizon when, for less than one minute, the ridge line “lighted up.” I actually had to desaturate this image in order to make it believable. Enjoy, click on it for a larger view:
This was taken with a Nikon D800 and one of my favorite lenses, a Nikon 85mm f2.8 PCI tilt/shift architectural lens, my second favorite, especially found during this trip, is my newly acquired Nikon 24 mm PCI lens. The un-cropped image is 48 images stitched into an HDR 39744 x 7212 pixels image in size, or a whopping 20 x110 inches when printed at a very fine resolution of 360 pixels per inch fine art image, that is, it is NOT a ‘blown up” cheap poster image.
Note that this image does not represent an actually full quality printed image, the Moon here is merely a white disk, whereas, in the actual full quality print the Moon’s features, as well as many other features, are clearly quite visible and really quite breathtaking.
Here is a quick video with my first prototype two axis gimbal with my Nikon D800 with a 10mm DX fisheye lens attached. Note the heavily overloaded vibration dampers were actually being supported by zip ties, obviously not very effective. But you can see exactly when one of the motors hit maximum thrust, the ESC LED turned yellow, the drone started shaking and within a few seconds it no longer could maintain altitude. By about 30 seconds three of the four motors were maxed out and it became uncontrollable and flipped on crash landing at about 38 seconds, Nothing broke
The aircraft weighed exactly 12.0 lbs. or 5443 g. This means about 1360 g of thrust was needed per motor in order for it to hover. The DJI E800 could not supply this much thrust for more than twelve seconds, the motors were very, very warm after this 40 second flight. There was little or no control possible once the aircraft started loosing altitude. Post flight battery voltage was 24.91 V. So much for their 2100 g of thrust rating. Proof positive DJI does not live up to its own specifications.
By the way this copter worked spectacular with my lighter Nikon J1 weighing in at at only eight pounds or about 900 g thrust required per motor.