Wednesday, November 21, 2007

 

The Grand Canyon Flights


The Grand Canyon certainly is one of the most impressive natural structures of this planet. It is situated in Northern Arizona and has an unbelievable length of 450 km, its width varying from 6 to 30 km. One distinguishes the higher North Rim, the South Rim and the Inner Canyon; the depth is up to 1.8 km and thus it is no wonder that on the way down through five different climatic zones both flora and fauna change significantly.
Natives already lived here some 3,000 years ago, but it wasn't until 1540 that a Spanish expedition (who else at that time!) first reached the South Rim – they were impressed and realized it was impossible to cross the canyon. So they left, and it took more than 300 years until the first serious explorers and cartographers came back to the area.

How did the Grand Canyon came to be? About 70 million years ago the Rocky Mountains were born and blocked the Colorado River which used to flow in south-eastern direction. So it changed its path in western direction, right across the newly formed Colorado Plateau. The rock there was comparatively loose and melted snow and ice from the Rockies let the Colorado grow into a mighty river; an unstoppable erosion process started, and here we are, 50 million years later, left breathless with such an incredible piece of nature.
Guess what – the UNESCO guys were also here! In 1979 the Grand Canyon was added to the list of world nature heritage. We really wonder when these guys will show up in our backyard at home …



After exchanging the main drive wheel of the Three Dee MP-XL I thought it was a good idea to do a quick test before flying it out over the Grand Canyon. Some guys who know me personally will smile now, but: With age comes wisdom …! ;-)
All kidding aside, the problem was that the whole area is densely covered with trees; except the roads and the parking lots in the Grand Canyon National Park there are no suitable spots for flying. We drove 25 miles through the park and finally found what appeared to be a former road into the woods. It was quite covered with trees, too, but at least reasonably firm soil so the heli wouldn't disappear in a cloud of dust during take-off and landing. I lifted off – nothing unusual. The gears were louder than normal but that's nothing uncommon with new gears. After 10 seconds I got bored and did a couple of precision flips between the trees. Everything seemed fine; very well then, back to the canyon!

It is until the very edge of the canyon that the terrain is completely covered with trees – one more step and the mighty canyon opens up before your eyes. Wow! – There is no words for this. One keeps looking in all possible directions, desperately trying to get this view under control; the sheer size and depth of the structure are just unbelievable. And now comes the problem …
The human eye and brain are a marvel that technology will never be able to hold a candle to. Capturing ultra-wide structures like the Grand Canyon is generally a big problem: The picture of any type of camera is limited! Granted, you could use special wide-angle lenses – but then the only way to create impressive scenes is to project them onto a large cinema screen. And even this leaves you with the danger of picturing just a plain "wallpaper" with not much of a depth perspective. Next issue when going for panoramic or full shots are the shadows. On the one hand they help you to add a third dimension to the scene – that's good! On the other hand this generates a high contrast situation – and that's very bad! Once again, other than the human eye film cameras – and especially digital video/photo cameras – have a very limited contrast range. Or in other words: If you don't want smaller details to break away in brighter spots the camera has to reduce the luminance of the picture. But this comes at a price: In the darker regions of the picture some objects will blend in with the background. So isn't it possible to brighten the picture just in the darker regions while not sacrificing details in overexposed spots? You'll guess the quick answer: No, you can't (you'd loose contrast!). It all boils down to increasing the dynamic range of the recording device, and like said before there is only so and so much that technology is capable of. Also think of videos of 3D aerobatic flying: When the sky is clouded and thus much light is reflected and the heli suddenly goes down and flies below the tree line it just disappears in the dark.

Okay, so we obviously have a problem – how can we fix it? Well, depending on what you actually want to express and to show with your pictures there is a number of things you can do. Even though it is very interesting to discuss such camera related problems, let's just focus on our very situation.
To add depth to still shots you will want to add "layers" to your picture. Find a bush for the foreground, then place the main object (person, heli, etc.) behind it, further in the background could be a distinct mountain, and only then follows the "wallpaper" far behind. Have a look at the shot below, it's quite three-dimensional.



Compared to still photography filming is always more difficult but at the same time greatly increases your possibilities. We wanted the viewer to first focus onto the helicopter and not to reveal the incredible backdrop at once. So at first the camera follows the heli with a close-up or at least a medium long shot while it is travelling towards us more or less along the edge of the canyon. At the point where it is closest the picture is almost fully open (heli still big!); the machine then dives down into the canyon, the camera zooming behind. It glides to the right and starts kind of a nose-in pie dish manoeuvre. The camera does not follow anymore but now opens the picture – wow! The vast size of the canyon becomes obvious while the heli gets smaller and smaller; the picture now slightly pans to follow the motion of the aircraft. When returning to the cameraman and pilot the picture again zooms in. Very impressive!
This simple kind of camera movement solves a couple of problems at the same time. First, the heli is presented to the viewer; his attraction is not torn between what the machine is doing and where it is flying. In addition, limiting the view quite effectively avoids bright and dark spots in the same picture; thus it is easy for the camera's automatic mode to light the scene correctly. Third, there's the "wow!" effect when the picture finally opens and the heli glides over the vast canyon structure.

The above sounds simple – and that's what it is in principle. However, good timing is required to create the "magical" scene we were looking for. It took us 2.5 battery packs to achieve an acceptable result. This means there was not much airtime left for still shots; so unfortunately we had to compromise a little on those.



Flying over the Grand Canyon was different from all other flights before. To get rid of the trees in the foreground and avoid disturbance by other visitors of the national park we had to climb down a couple of meters into the canyon. Not so easy with a helicopter, transmitter, battery packs, cameras and a tripod; one wrong step and you may end up on the rocks a kilometer beneath you! Same problem while flying and filming: You focus so much on the heli and the camera picture that the reference around you for keeping the balance is somehow missing. It feels somewhat like standing on top of a ladder while looking up into the sky; only the drop is a little longer … Now does this mean you have to stand directly at the edge?! Yes of course, how else could you fly and film down?! :-)



Crashing into a river, the sea or also into difficult terrain like at the Great Wall of China means the heli is completely lost – no way to get it back. But it was never more obvious then when flying over the Grand Canyon; the heli flies out and dives down until it is a mere speck in the sky, soundless, somehow lost in an unbelievably wide environment, gliding 1.5 km over the ground. I nearly got a heart attack when all of a sudden the tail swung around!
Emergency landing. Hell, what was that?! I had a very close look at the whole helicopter but couldn't find anything. After watching the situation on the video a couple of times I decided it was an RPM problem. Now how's that possible?

A couple of people have noticed (and asked by email) we sometimes use Kontronik's Power Jazz 63 V as electronic speed controller, and some other times the big Schulze ESC. The governor mode of Kontronik ESCs is legendary, and we use Kontronik equipment in pretty much most of our electric machines. However, when flying with throttle curves rather than flat lines (i.e. governor mode) we often prefer the Schulze controller. At the Grand Canyon site we wanted the heli to dive down into the depth as smoothly as possible. It looks best if you do not force it down in 3D mode or with constant RPM, but if you actually let it autorotate; in other words a throttle curve will work best in this case. Again this comes at a price: You cannot fly fast backward autos and/or do pirouettes forever. There is a point when the tail comes round and the machine "locks" into forward flight. That's what caught me a little by surprise, so … phew!

The 800 km drive back to LA was smoother than expected, and we had half a day left for visiting the Universal Studios; as cool as always. Personally I'm pretty sure that if I started my life again, I'd become a filmmaker. Isn't HeliGraphix moving more and more towards filming anyway? That's true; still there is a significant difference to Hollywood (at least up to now): HeliGraphix is NO special effects! Every second of film footage you see is REAL! Real people, real stunts, real adventures, real helicopters, real challenges, real crashes in a real world! Our life is no different from yours – that's what makes HeliGraphix so exciting, so tangible, so cool. And so insane … ;-)


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# posted by hg/tuw @ 21:00
Comments:
Wooooooow!!! Amazing pictures... :-) Amazing action :-) Insanity at a whole new level ;-)

I just have one problem: I can't use the pictures as a desktop wallpaper... My Screen ist too big... (nobody has 1024x786 anymore) :-)
It would be really really great if you could upload some high-resolution Wallpapers on the Heligraphix-Page :-)

Greetings from cold gray old Switzerland... :-)

Sam
# posted by Anonymous Anonymous : November 22, 2007 at 10:40:00 AM GMT+1
 
Good point Sam! I also streched the small pictures on my 1680x1050 22" widescreen and it looks... well, not good! :P I liked the Ayers Rock & Grand Canyon most so far and I would appreciate higher res. pics on the HG site too :)

@ Tobias & Saskia - may the force be with you!

Greets from Southern Germany,
Marc - the Interpreter
# posted by Anonymous Anonymous : November 22, 2007 at 4:58:00 PM GMT+1
 
Thanks for the great comments - and no worries, we'll work on the desktop wallpaper issue after finishing this part of the WSF - also for those of you using 20 million x 16 million pixels. ;-)
The pictures for the blog need to have a more or less universal size for all the different resolutions out there in the world.

Regarding all the other comments and emails so far, we'll probably come up with a Q&A post when we find the time (hmmm ...). :-)
# posted by Blogger hg/tuw : November 24, 2007 at 7:43:00 AM GMT+1
 
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