Byte by Bite

Needs Headline

by Marv Dealy

First thing Tuesday, I opened up Google Earth to see the proximity of the fire and what natural barriers were between it and the greater metropolis of Big Oak Flat. I was pleased to see that new imaging data had been added since last I fiddled with Google Earth, and enough data were now present to zoom in on the buildings around Moccasin, Big Oak Flat and other south county towns that had previously not been well represented.

In fact, zooming in on Big Oak Flat, I could see my office along Highway 120, as well as the Big Oak Flat ball field, both quiet clearly.

Interestingly, the new satellite sweeps split Moccasin Peak down the middle, with the sweep to the west being a “lighter” image and that to the east being somewhat darker. Zooming in to an eye level of about 3,150 feet, just a little over 200 feet above the roofs of the couple of buildings visible on top of the peak, I could see tire tracks surrounding the buildings and the road to get there that branched off from Marshs Flat Road, back to the south and east and some 1100 feet lower, according to Google Earth.

I decided to fire up Microsoft’s Live Local to see what detail it showed for the same area and found color satellite photos when zoomed out to what the scale said was 1 mile (to an inch and three quarters on my ruler—what bizarre scale is that?) that switched to black and white upon zooming in any closer. At the closest zoom level, which the scale called 30 yards, no photos were available.

By contrast, Google Earth’s photos remained in color as I zoomed in to abut 200 feet above the old power house at Moccasin, about the point at which the picture begins to blur enough as to not be useful. The Google Earth tool that allows you to move from a straight down view to one looking more from the side—allowing for terrain features such as Moccasin Peak to be clearly visible in three dimensions—made it easy to see the natural features that would hopefully slow the Pedro fire’s movement toward the east.

From the 3D images, I could see that the fire would have to crest Moccasin Peak, cross both Hwy. 120/49 and Moccasin Creek, and move through Moccasin before it could begin the advance up Priest Grade toward Big Oak Flat.

There are other notable differences between Google Earth and Live Local—the “close up” pictures in suburban areas are best with Live Local, even if it’s not really live, real time. The photos of San Francisco, for example, are startlingly clear in the “bird’s eye” mode, taken from airplanes with what must be incredible cameras rather than from satellites. The ability to rotate around a subject of interest such as the arboretum in Golden Gate Park with such crisp imagery is incredible.

Google Earth, on the other hand, does a better job at letting you view topographical features, such as Half Dome from the above, or zoomed in and around from whatever direction you want to see the Dome. While exploring Moccasin Peak, I got sidetracked with Google Earth and ended up “flying” up the Tuolumne River canyon, stopping at Hetch Hetchy dam before jumping over to the Yosemite Valley where I virtually flew up and down the valley, below the canyon walls.

I zoomed over the Awahanee, and was able to rotate it so that I was looking down into the large lawn area behind the hotel and bar area; after being there so many times—including, I’m told, my very first summer while my parents were working at the park—it is quite something to see it from about 250 feet above the valley floor on my computer screen.

I took a break from Yosemite Valley and used Google Earth to “fly” down to San Francisco. The Ferry Building tower loomed large and the restored plaza where once was the double deck Embarcadero Freeway looked great. The distortion of the tall buildings when I used the tools to move from straight overhead to a sideways view, however, was disconcerting. I spun the picture around and zoomed up Market Street, heading west toward Twin Peaks. I zoomed in to about 50 feet above the street level, and used the pan and tilt tool to see the buildings, streets and vehicles pictures; they all looked flat and one dimensional, even with the shadows. Even the trees looked one-dimensional.

An odd effect happens when you turn on the “3D buildings” feature in Google Earth—all the buildings along Market Street suddenly spring up as computer-generated gray monoliths, each of which roughly describes the shape and height of a particular building.

For comparison, I used Live Local to look at the same San Francisco neighborhood. I located the tower on the Ferry Building one again, and the pictures were incredible this time—clear, amazing detail, etc. But, it wasn’t as easy to navigate around as it is in Google Earth. Here I was limited to four 90 degree choices on the compass, rather than panning around as I chose. And, there wasn’t any option to tilt the view as in Google Earth, and I had only one “zoom” option and couldn’t get virtually down between the buildings.

The imagery in Live Local is good enough however to see when the photo was taken. Looking from the west the clock on the Ferry Building tower was showing 15 minutes after 5, and from the shadows we can assume that was in the afternoon. Out of curiosity, I changed the view from looking from the west to looking from the north, and the clock showed 3 pm. From the south, it was 4 pm, and from the east, about 3 minutes after 5 pm. I don’t know if these pictures were taken the same day, although the lighting conditions were pretty similar.

Each of these programs has its benefits and draw backs—if you want to “fly” through a geographic area or city or whatever, you’ll need to use Google Earth. If you want to see startlingly clear photographs of major US cities—and as of this writing that doesn’t include Sacramento, much less Oakdale or Copper or Sonora or Murphys—use Live Local.

A warning is in order here—every time I show these tools to someone when I leave they’ve fallen into a black hole where time passes without noticing. Once you start poking around you’ll find you can see the Statue of Liberty in startling detail with Live Local, but with Google Earth you can “fly” around the statue. Another warning—you’ll be wishing you had a newer computer if you try this with an older one with a slow graphics card and processor and not to much RAM, and you’ll most certainly have time for lots of coffee breaks if you try these programs with a slow, barb-wire-fed Internet connection.

Live Local is a browser-based program; go to http://local.live.com, enter the address or name of the place you want to see in the search window and off you go. If it’s an area that has aerial photographs a “bird’s eye” view will be available with those spectacular close-up pictures, if not just road maps and satellite shots. Google Earth is a program you have to download and install—find it at http://earth.google.com.

And a Friday freebie—if you can’t get to Lake Tahoe this weekend, Google Earth has high resolution images that’ll make you wish you were there—you can see Fannette Island from a perspective previously only available to helicopter or airplane passengers. Apparently due to the angle of the satellite when the photos were taken, Vikingsholm is not visible in these images nor is the teahouse on Fannette Island particularly visible. For that, see a picture I took while in the vicinity last summer for a wedding at http://throck.com/jjwedding/LakeTahoe/pages/FannetteIsland2.htm