The NGM inner investigation has evaluated all (?) data, and found them authentic. Furthermore, some technical
details of the cover photograph (Kingfisher) have been released. According
to the released data, the cover photograph had been taken with the
following equipment and settings:
Starting from the above information and assuming that a live Kingfisher (Alcedo atthis) was captured on the photograph that followed the genetically encoded behavior of the species, we can assume that it arrived with a 35-55 km/h speed of a horizontal, straight flight above the water surface. This speed was necessary for the bird to avoid falling into the water.
Capturing the bird with such a high speed raises two problems:
1./ Shutter speed of the camera
The 55 km/h corresponds with 15 m/sec and 35 km/h = 10 m/sec.
Even if we do not calculate with the significant lag of the shutter (we just set it to zero), then our calculation indicates that the shutter should be pressed when the bird is not even in the viewfinder; it is 2 m away from it. The bird's path is unpredictable from such a distance. Thus, we can exclude this exposition method (which is unprecedented in international practice...).
The only method is the infra (or laser) gates and the careful setup. The portrait format, the almost perfect composition (even at the reflection) and the setup of the flash lighting (discussed later) that required a second flash unit at a certain distance from the camera indicate that the setup had been planned in advance. It is further supported by the picture's fantastic message: the dramatic moment of catching the prey (please note: there is no picture in the literature with a Kingfisher hunting on a prey that is floating on the water surface; not even similar to that!).
Assume an extreme fast system with zero millisec lag (of course, there is no such a system). Assume that the author has such an infra gate. We still have to calculate with the camera's lag period.
Therefore, there is no international practice or references that recommend this camera model for infra gates. Will the question remain open? Is there any method but miracle with which the author could manage to take this picture of a naturally behaving animal with the disclosed equipment? Below we are going to answer this question!
2./ Flash lighting:
According to the literature and our own experiences, we can state with full confidence that the flash output significantly decreases with decreasing the duration of the flash.
The 0.1 cm movement is small enough to result in a sharp image because it will be further decreased by the …
According to our measurements the 1/16 power equals to 1/6000 flash speed. It won't freeze the bird's wing tips. Let's assume that the next energy level, 1/32 will do it.
What is the minimum distance between the flash and the subject that still provides the appropriate amount of light applying 1/8,000-1/10,000 sec speed?
According to our experiences, stopping down the maximal output at 1/16, acceptable result can be achieved but the very ends of the wings would still appear blurred. Assume that at 1/32 stop this blur would be unnoticeable.
Let's see the appropriate aperture values for 100 ASA film at 1/16 stop of the two flashes' from 1m, 2m, 3m, and 4m:
1m = f11
The aperture values at 1/32 flash output:
1m = f8
Everybody in this field should know the reciprocity rule. According to our experiences, 1.5 times wider aperture values should be applied for correct exposures in such conditions. Therefore, the aperture values corrected by the Shwarzschild effect are the following at 1/16 flash output:
1m = f11 ^ 1.5 = 5.6-8 (5.6 and a half)
The f values at 1/32 flash output:
1m = f8 ^ 1.5 = 4-5.6 (4 and a half)
Furthermore, because the distance between the flash units and the subject should not exceed 0.5-1 m, the photographer faces a new problem; in order the flash lights do not cast a shadow of the bill on the bird's abdomen (as there is NO shadow on the picture), the flash units, with 400 mm lens, have to be placed on the line of the bill's extended axis. Placing the flash units there would cause them to appear on the picture (with 400 mm lens). As they do not appear on the picture, we can exclude that they had been placed there.
We can conclude that the flash units were positioned in a higher distance than 0.5-1 m. However, in this case, the flash units cannot provide sufficient output for taking a similar picture of a live animal.
Therefore, we can exclude a 400 mm lens based on the flash units' performance and positions! (Otherwise, the bird has to be motionless!)
Background lighting:
Explanation:
The light intensity exponentially decreases with the increase of the distance. The light rays to different points of the background travel significantly different distances from the artificial light source if it is positioned relatively close to the subject. Thus, different parts of the background are lit unevenly. If the light source is the sun, this effect is missing due to the quasi infinite distance of the sun. The unevenly lit water surface excludes natural lighting!
Lens: 5.6/400 mm
The disclosed lens parameters rise further questions:
During probing of the theme we concluded that the depth of field on the picture is at least 4 cm. However, the actual depth of field of a 400 mm telelens at f5.6 at 4 m from the subject, which is the required distance for this theme, is 2.5 cm only. Therefore, either the f value or the lens type is wrong (or both). A 400 mm telelens would surely cause more compression in the perspective. Thus, we can conclude that a shorter lens was used for this picture.
Using a stuffed bird we reconstructed the theme of the picture(18. picture), and set the lenses so that the depth of field was 4 cm.
At 25.1 micron CoC value the DOF calculation resulted in the following f stops:
- 100 mm lens, 1 m subject distance: f8.5
- 200 mm lens, 2 m subject distance: f8.5
Above data and an earlier conclusion that the flash units were in close proximity to the lens, convinced us that a 100-200 mm lens was used for this picture, possibly with a twin macro-flash unit that provided the appropriate key lighting from close proximity of the lens avoiding casting a shadow of the bill.
However, with this setup, it is almost impossible to get a sharp picture of a bird due to the low output of the flash units, even if the bird moves relatively slowly.
In summary, above contradictions are unexplained on the cover photograph; the significant difference (40x !!!) between the shutter speed used for the ambient light and the flash speed (1/250 vs. 1/10,000 sec). Well noticeable "ghost" effect should appear on the picture if the bird was really moving.
We can conclude that the picture illustrate:
Considering all these conclusions, how can someone claim that the picture illustrates a real situation in the wild?
None of the information pieces gained during probing the picture supported such a claim. Only the NG experts, who are still unknown by us, and whose explanations should be compared to ours, support that claim.
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