Let us examine Allan Sturm's work on this page:
http://www.lunomaly.com/en/other-ima...ellanious.html
The first section contains four photographs. The bottommost is an original image. Moving up, we find the same image desaturated presumably to obtain density information. Then we have a pair of detail images taken from roughly the center of the source images.
The first error Sturm has committed is to have failed to control for the obvious chromatic errors in the source digital image. This is an artifact of the scan that produced it from the original transparency. It will not produce a usable density map.
The source image displays coarse spatial resolution. It does not support the resolution at which Sturm has made his interpretation.
It also displays coarse, stepwise luminosity information. This is usually the result of an uncalibrated scan, or possibly exposure problems in the original transparency. However in Sturm's massaged copies, smooth gradients are suddenly available. There is no explanation for why that information suddenly appears when the appropriate detail is clearly blown out in the source image.
The problem is that those mysteriously created gradients then become contour cues. That coupled with the loss of spatial detail drives Sturm's interpretation of objects such as spoked wheels, that are illustrated in his annotated detail.
Ordinarily an interpreter would apply global illumination cues and automated (not subjective) contour-extraction techniques here. Instead Sturm has simply drawn lines on his heavily massaged image based on his imagination.
The red annotations at the top unfairly regularize structures. In one case the spatial resolution does not support Sturm's interpretation of a foreshorted straight line and right angle. If you return to the larger image, there is no supportive alignment with the global environment. Further, Sturm unfairly regularizes features that are clearly not so, even at that coarse resolution. That is obvious cheating.
The orange annotations in the center merely subjectively outline interpretations of contour. They do not fit any spatially coherent structure or arrangement. In the case of the "wrench" shaped feature, Sturm has simply made that up -- it does not appear in his source images.
The red annotations present the spoke-and-wheel interpretation, but again there's no case for a coherent structure. The "contours" arise simply from Sturm's misguided requantization and smoothing of coarsely discrete data.
Elsewhere on the site Sturm gives an example of a detailed aerial photograph that has been coarsely resampled and then filtered back out to a higher pixel resolution. He argues that it is still valid to perform interpretations on the filtered image. This is not correct. The validity of his interpretation depends on presuming the fine detail that is lost does not contradict the interpretation. This is what we saw with the Cydonia photographs. The filtered image with low spatial resolution conveyed a sense of regularity that was simply not valid when more detailed photographs were obtained.
Sturm simply falls into the same trap as have all prior novices: he ignores the perceptual effects of the smoothing that is inherent to both digital and photochemical photography. One cannot presume the absence of contradictory detail just because one cannot see it. This is elementary photographic interpretation.
The next section is entitled "Some miscellaneous early finds."
Judging from the subject matter and the inclusion of a reseau fiducial, the first photo is from an Apollo lunar surface EVA. It appears motion-blurred along a path inclined roughly 40 degrees to the right of vertical.
No interpretation is presented, but we can surmise that the object at the center is the one Sturm purports to be interesting. At first glance it may seem to be a cylinder protruding from the regolith, with an inset cap. However, we see that the long edge of the "cylinder" does not continue, and we see that the "cap" is not sufficiently regular to be an elliptical foreshortening of a circle. It fails the test of uniformity.
The following photo is simply a blob with no context.
The third photo in this section appears to be a highly-expanded excerpt from an orbital image. There is clear evidence of smoothing and interpolation. This will naturally introduce a false sense of regularity.
It appears Sturm has attempted to connect the two dark patches in the center as a single object that is punctuated by the somewhat vertical feature. In fact the two dark patches are unrelated; they are individual shadows of two roughly parallel ridges. Because the spatial quantization and subsequent smoothing has eliminated the detail in these shadows, they are incorrectly assumed to be smooth-edged, round, and perhaps connected.
The next section entitled "Lunar tumbleweed with grid" presents Sturm's isolation of a feature which he colors green in his annotated version.
With absolutely no argument or justification, Sturm seems to claim that this feature is standing up from the surface. He simply mistakes coloration as contour. This clearly violates his admonition to "look through" the photograhph, since he has made no confirming argument that this "tumbleweed" is in the geometric configuration he seems to purport.
The next section is entitled "Another grid example" and purports to show a regular square pattern of crater-like features. Presumably uniformly or regularly spaced features were also to be seen in the prior "tumbleweed" image, but I failed to find any.
There is a huge difference between objects that only seem somewhat regularly spaced at first glance and objects that are indeed regularly spaced according to a simple pattern and measured at an appropriate tolerance. Here no attempt is made to establish that rigor. No consideration of surface contour occurs. No deference is made to the low angle from which these features are photographed, which would tend to obscure gross differences in distance along the line of sight.
The final section "Interesting geometry in Lunar Orbiter Image" is the
coup de grace. The feature Sturm has isolated in his insets is simply the extension of an imaging artifact that is clearly visible above it in the dark portion of the image.
In short, Allan Sturm is clearly an amateur at photographic interpretation. He commits nearly the all the errors an untrained amateur would be expected to commit. This "analysis" is worthless.
06-November-2009, 07:26 PM
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