ow. quit it. ow. quit it.

The background images of PAIN
Tags: , ,

GPS confusion

  
37 46' 15.5" N 122 24' 41.9" W +50'
Since the site went up, the DNA Lounge Directions page has had a little map on it, with the ICBM coordinates of the club below it. I got these numbers by digging them out of the URL of some mapping site or other (I no longer remember which.) Well, the other day I got mail from someone who said that he had punched my coordinates into his GPS box and:

Bart Smit wrote:
I discovered the following:

As no datum (geodetic reference system) is given, one is tempted to interpret these coordinates as WGS84 (the standard datum for gps). However, this would let the DNA Lounge sit on Harrisson towards 10th, which is more than 90 meters off.

If I assume that the coordinates are referred to the North American Datum of 1927 (NAD27), which has been the standard datum for USGS maps for a long time, and then plot the position of the DNA lounge on a map, the result looks much more plausible. See attached image, which is a small section of a scan of the SF North Quadrangle map from USGS's 7.5 minute series. The circles represent the margin of error of a GPS receiver.

Perhaps you could clarify on the web site that the given coordinates are NAD27 (are they?), or else use the WGS84 coordinates, 37 46.252' N, 122 24.761' W

A "geoditic reference system" is apparently a way of mapping the spherical coordinates (latitude and longitude) to points on the surface of the earth: this is not a 1:1 mapping since the earth is not a sphere. It seems there are a number of different "geoids" used for doing this, and different maps use different ones.

So I'm trying to figure out what the "right" ICBM address for the club is. GeoURL lists a few ways to find your coordinates. You can find yourself in Yahoo Maps or Tiger Maps and dig the lat/long out of the resulting URL; or you can go to Poskanzer's super cool ACME Mapper which uses the TerraServer data, and lets you type in lat/long, among other things.

I found DNA's coordinates in various places, plus netik brought his GPS down and got numbers from that. These numbers are (well, I want to say "all over the map,", ha ha, but actually are just) slightly off.

  • When looking at these numbers in the ACME Mapper, Yahoo and Tiger are in agreement with ACME, so presumably they all use the same system. Is this NAD27?
  • My old numbers and netik's GPS numbers are pretty close to each other, and both put show up in the middle of the CostCo parking lot down the street.

  • Bart's numbers, which he says are WGS84, show up basically next door (inside the glass block place.)

I am confused about A) what the "right" reference system to use is, and B) about what reference system is being used by the various mapping sites. Is it the case that the mapping sites use a different reference system than GPS receivers use? That would be pretty silly, if true...

  Source:   Lat (dec):   Long (dec):   Lat (deg):   Long (deg):   Via ACME:
Bart 37.7709 -122.4127 37 46' 15.24" -122 24' 45.72" Glass Block
Netik 37.771008 -122.411750 37 46' 15.629" -122 24' 42.3" CostCo
jwz 37.77097 -122.41164 37 46' 15.5" -122 24' 41.9" CostCo
Yahoo 37.770960 -122.412794 37 46' 15.456" -122 24' 46.058" DNA
Tiger 37.7710686 -122.4127808 37 46' 15.847" -122 24' 46.011" DNA
ACME 37.771019 -122.41273 37 46' 15.668" -122 24' 45.828" DNA

(See also RFC 1876, where you can include your lat/long in DNS, to make tools like XTraceRoute work better!)

________________________________________

Update:

Dan Egnor wrote:

TIGER (since 1995) uses NAD83, not NAD27 (except for Hawaii and Pacific islands). Many commercial mapping data suppliers (such as those which the likes of Yahoo Maps use) start with TIGER data. The Census Bureau point out that the "likely coordinate shift between NAD83 and WGS84 is much smaller than the nominal accuracy of the TIGER/Line files".

Based on my experience TIGER/Line and commercial mapping engines intended for casual use (as opposed to professional GIS, or USGS maps) are simply not very accurate -- I mean, why bother sweating the small stuff as long as the map looks OK? I suspect that's the cost of most of the variance you're seeing, not datum mismatches.

So this means that the truthful answer would be to use the coordinates we got from the GPS, which are in WGS84, even though those coordinates show us to be almost 90M east when fed into the ACME, Yahoo, and Tiger sites.

Kinda lame!

Tags: , , , , ,

GeoURL ICBM Address Server

GeoURL is a location-to-URL reverse directory. This will allow you to find URLs by their proximity to a given location. Find your neighbor's blog, perhaps, or the web page of the restaurants near you. Add yourself to the database.

For an example, check for sites near New York City and San Francisco.

Tags:

TV Ads Say S.U.V. Owners Support Terrorists


RealVideo here
, but "the RealServer has reached its capacity, try again later."
TV Ads Say S.U.V. Owners Support Terrorists

WASHINGTON, Jan. 7 -- Ratcheting up the debate over sport utility vehicles, new television commercials suggest that people who buy the vehicles are supporting terrorists. The commercials are so provocative that some television stations are refusing to run them.

Patterned after the commercials that try to discourage drug use by suggesting that profits from illegal drugs go to terrorists, the new commercials say that money for gas needed for S.U.V.'s goes to terrorists.

"This is George," a girl's voice says of an oblivious man at a gas station. "This is the gas that George bought for his S.U.V." The screen then shows a map of the Middle East. "These are the countries where the executives bought the oil that made the gas that George bought for his S.U.V." The picture switches to a scene of armed terrorists in a desert. "And these are the terrorists who get money from those countries every time George fills up his S.U.V."

A second commercial depicts a series of ordinary Americans saying things like: "I helped hijack an airplane"; "I gave money to a terrorist training camp in a foreign country"; "What if I need to go off-road?"

At the close, the screen is filled with the words: "What is your S.U.V. doing to our national security?"

<LJ-CUT text=" --More--(40%) ">

The two 30-second commercials are the brainchild of the author and columnist Arianna Huffington. Her target audience, she said, is Detroit and Congress, especially the Republicans and Democrats who last year voted against a bill, sponsored by Senators John McCain, Republican of Arizona, and John Kerry, Democrat of Massachusetts, that would have raised fuel-efficiency standards.

Spokesmen for the automakers dismissed the commercials.

Eron Shosteck, a spokesman for the Alliance of Automobile Manufacturers, said of Ms. Huffington, "Her opinion is out-voted every year by Americans who buy S.U.V.'s for their safety, comfort and versatility." He said that S.U.V.'s now account for 21 percent of the market.

In an interview, Senator Kerry distanced himself from the commercials. He said that rather than oppose S.U.V.'s outright, he believed they should be more efficient.

"I haven't seen these commercials," he said, "but anybody can drive as large an S.U.V. as they want, though it can be more efficient than it is today."

Ms. Huffington's group, which calls itself the Detroit Project, has bought almost $200,000 of air time for the commercials, to run from Sunday to Thursday. While the group may lose some viewers if stations refuse to run the advertisements, the message is attracting attention through news coverage.

The advertisements are to be broadcast on "Meet The Press," "Face the Nation" and "This Week With George Stephanopoulos" in Detroit, Los Angeles, New York and Washington.

But some local affiliates say they will not run them. At the ABC affiliate in New York, Art Moore, director of programming, said, "There were a lot of statements being made that were not backed up, and they're talking about hot-button issues."

Ms. Huffington said she got the idea for the commercials while watching the antidrug commercials, sponsored by the Bush administration. In her syndicated column, she asked readers if they would be willing to pay for "a people's ad campaign to jolt our leaders into reality."

She said she received 5,000 e-mail messages and eventually raised $50,000 from the public. Bigger contributors included Steve Bing, the film producer; Larry David, the comedian and "Seinfeld" co-creator; and Norman Lear, the television producer.

Katharine Q. Seelye

Tags: , , , , , ,

Female or Shemale?

Female or Shemale?

I only got 10/16!

Tags: