out, including each of a small group of players who seem to have the right answer nearly every day. Terdiman asked those players to share their techniques on identifying the images, and they did." credit="Daniel Terdiman/CNET" alt="" creditUrl="" targetUrl=""/>
What I never expected, though, was the tenacity of some readers in trying to identify each day's mystery photograph, nor the clever and often complex methods some employ in doing so.
If you haven't been following the Picture of the Day, I've been posting an image every day since June 7 and tasking readers with figuring out what it's a photograph of. Since then, I've gotten nearly 4,200 total submissions, and I've watched as a series of the same names come up with the right answer day after day.
To which, I must admit, I've been duly impressed. After all, as part of the series, I've posted quite a number of pictures that, if I hadn't taken them myself, I never, ever would have been able to pinpoint. But day in and day out, some of these folks have worked out the problem, and dutifully sent me their answers.
Some of the pictures, of course, have been simple. That's why, for example, 551 people knew that the June 27 image was of the U.S. Bullion Depository, otherwise known as Fort Knox. But sometimes, fewer than 20 people knew the answer. Once, with the July 12 photo of the StorageTek Automated Cartridge System located at the National Cryptologic Museum, just 17 people got it. But among those few were those same familiar names. And after watching them solve even the hardest ones, I knew I had to get them to spill the beans on how they were doing it.
So I asked three of them (and I do recognize the rest of the regulars' names), and even though it wasn't in their interest to do so, all three explained their methods.
"I start every Picture of the Day Challenge by making an initial guess as to what the picture is of," said Jeff Cousens, of Evanston, Ill., told me earlier this month. "For example, when I saw the picture for July 13 it instantly said cornerstone. I then look for distinguishing characteristics. For the 7/13 picture, the engraved '1930' is an obvious candidate. Finally, I try to narrow down the location, if I can. This has been a lot of guesswork, but...we know that...Road Trip 2010 started out in Washington, D.C., and has been to Virginia, Maryland, Pennsylvania, New Jersey, and New York. Looking at the 7/13 picture, you can see lots of tall buildings and crowds in the reflection. New York City seemed like a good starting point.
"I then formulate a query, type it into [Google Images] and look for something that resembles the picture. For 7/13, I got lucky. My first query was '1930 cornerstone nyc' (without the quotes). It just so happens that the first result is an almost identical shot on Flickr. If I'm not positive as to the result, I'll then use the presumed identity to search for more images. Fortunately this was a pretty good match, as there may not be another easily found image of the Empire State Building's cornerstone online."
Of course, the Empire State Building cornerstone wasn't all that hard. But Cousens was one of the eight people who got the Old City Hall in Richmond. Here's how he got that answer:
"Looking at the picture, many things stand out: The building appears to be older;...it appears to be Gothic architecture; it features an eight-story clock tower; it is asymmetric; the floors appear normal, so it is most likely an office or classroom building, rather than a church," Cousens explained. "And the setting is urban, but not densely populated. While that all seems very specific, nothing is enough to make this one obvious."
"I went through dozens of combinations of 'clock tower' and 'gothic' with [eastern state names]. I mixed in 'office building,' 'church,' and 'cathedral....I tried a few of the more obvious colleges...Nothing. Finally...I tried Bing [and] Bing's searches were returning fewer results, and they appeared to be better results. So I started over, [and] 'Gothic clock tower Virginia' was the winner, returning a mere 17 results on Bing...of which 3 results are of the Old City Hall, taken from a different angle. From there, it was just a matter of searching for 'old city hall Richmond' to confirm that this was, indeed, the Old City Hall in Richmond, Virginia."
Another reader Michael Moretti, broke his method down into five parts: first impressions; identify; context; search; and verify.
Assuming he doesn't instantly recognize the picture--which he said has almost never happened--he tries to determine the subject of the image. Then, he ventures some educated guesses. "In the Cryptologic Museum shot, my first hunch was that it was a sound isolation booth," Moretti said. "I soon discarded that when I saw all the lights inside and thought storage. The red line at the top reminded me of the markings on Agfa electronics which led me to think at one point that it might be one of their products, perhaps mass storage for a publishing application."
Moving on to context, Moretti continued: "With the StorageTek image, I noticed the aluminum railing and security camera (I use Photoshop often to lighten darker areas of an image)....So, I started searching technology museums, primarily those dealing with vintage super-computing, mainframes, etc. (and again, on the Northeastern coast)."
Getting closer, Moretti then turned to what seems to be one of the Picture of the Day challenge solver's best friends: Flickr. "Google image search is my friend, but Flickr is really where it's at," he said. "I searched there with the details that I had collected in preceding steps. A little tedious, but if I've educated myself well enough up to this point, it'll go quickly from here."
Interestingly, both Cousens and Moretti mentioned that there had previously been just one image on Flickr of the "1930" Empire State Building cornerstone.
But before sending in his answer, Moretti has one last step: looking for corroborating evidence from several other sites. In the case of the Empire State Building cornerstone, he turned to Google's Street View. "I could make out the blue Chase logo reflected on the building across the street from the Empire State Building," he said, "and it was easy to count the stories on that particular building which I could do on both the photo and using Google's Street View."
Christopher Peterson, too, is a fan of using Flickr to solve the daily challenge, and I will always listen to what he has to say about this. From the time I started doing the Picture of the Day challenge in the middle of Road Trip 2009 until the end, Peterson was the first person with the right answer six times.
"For the Assateague Lighthouse, I went straight to Flickr," he said. Since "I knew you were in the Northeast and in a state with a shoreline, I used keywords of Eastern seaboard states such as 'Maryland + lighthouse.' When I entered 'Virginia + lighthouse,' there it was. To corroborate I pulled up all the photos of the Assateague Lighthouse on Flickr and found one that was nearly identical to your post."
To be sure, the methods these three use can be exhausting and can take some real time. I've heard several times from one of them, and from others, that it took them most of the day to figure out the answer. But I've also discovered that there are some easy cheats, especially if the subject of the image is fairly well-known. For example, many people have mentioned using Google Goggles to find the solution.
Yet, it was something that Moretti told me this weekend that made me change the way I post each day's picture. After reading an article by my CNET colleague Declan McCullagh about how metadata left attached to photographs can potentially betray information about where a photo was taken, Moretti confessed that he was able to retrace my Road Trip steps by going through a number of my photos and basically laying out my itinerary. He said was able to extract bits of the metadata by using Photoshop. And that made it easy for him to significantly narrow down what was in some of the photos.
I asked him what I could do about that. His answer, and what I'll be doing from now on: taking a screenshot of the Picture of the Day images and posting that. Sorry, Michael. You're going to have to work a little harder from now on.