A truly disturbing-looking photograph of what appeared to be a massive, bottomless sinkhole was posted on Flickr by the Guatemalan government on May 31, 2010 after the country was ravaged by Tropical Storm Agatha, killing more than 150 people.
The sinkhole appears to have opened in the middle of an intersection, and the most striking thing about the photograph is that the sinkhole is almost perfectly round — as if a giant drill bit were used to bore into the earth.
Because the sinkhole looks almost too “perfect,” questions quickly arose in the blogosphere about whether the image may have been Photoshopped or otherwise digitally altered.
But a close look at the high-resolution version of the photograph as well as an examination of previous sinkholes in the region suggests that the photograph is indeed authentic and un-tampered-with.
The Big Picture
The highest-resolution version of the image available is 3888 by 2592 pixels, or about 10 megapixels.
At this level of detail, it is possible to make out individual pieces of debris.
Normally, when one suspects that a photograph may have been digitally altered through Photoshop or other means, one of the first things one looks for is a difference in “texture” between the suspect element and its surrounding elements. For instance, the suspect element may have more JPEG artifacts than the elements around it, suggesting that it came from a more compressed image. No evidence of a difference in texture is visible in the sinkhole photograph.
Another thing to look for is a “seam” between the suspect element and the surrounding element — any sort of indication that the suspect element does not blend in with the background. But as far as I can see, the sinkhole photograph is seamless.
Yet another indicator that an image has been Photoshopped is a difference in perspective or lighting between the suspect element and surrounding elements. Again, there is no visible indication that such a difference exists in the sinkhole image.
Other Indicators of Authenticity
Yet perhaps the most convincing indicator that the photograph has not been tampered with is the fact that a similarly round sinkhole opened up in the same country only three years ago.
WebEcoist, in an article documenting some of the largest sinkholes in the world, has a picture of a sinkhole that looks eerily like the most recent one in both the shape of the hole and the texture of the earth inside it.
It is thus almost 100 percent likely that the most recent sinkhole photograph is authentic and has not been digitally altered.