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Streaked Light

April 2012

By Stephanie Bohn

Here we begin our series of articles outlining what we know to be common misinterpretations of collected evidence. As mentioned in our Introduction, many are not in possession of the necessary information to interpret what they see. Our hope is to present this information to others who want to know and learn. If groups claiming to use a scientific process truly desire to do so, then they must present results only after the consideration of reasonable explanations or facts.

The first example of “evidence” of the paranormal we would like to discuss is that of the light streak present in a digital photograph. The environment in the photo is dark, the flash has been used, and there is a light source as the point of origin from which a beam of light appears to be emanating. While preparing to write this article, we at NPI discussed what we thought groups might actually think this was. I was musing, “Do they believe the entity lives in the light source and it is jumping out? Is it taking hold of the light and stretching it like taffy?” We came to the conclusion that they most likely believe it is evidence of an entity attempting to draw energy from the light source in order to manifest itself. An understandable conclusion, I suppose, if one is unfamiliar with how a camera works in flash mode, which is with a slowed shutter speed.

When the explanation of movement in conjunction with slow shutter speed is offered, the first defense usually given by the individuals presenting the photo is, “but the rest of the photo is in focus.” There is a reasonable explanation for this, one that we have discovered is not widely known. When you enable your flash, your camera automatically lengthens the period of time that your shutter stays open. This is because the flash itself occurs in fractions of a second and your shutter (in the proper light) remains open for fractions of a second. It would be exceedingly difficult to synchronize the flash and the shutter, allowing them to operate at the same, precise fraction of a second, so the shutter stays open LONGER to give the flash a window within which to engage. While the shutter is open, any light source present in the darkened room will imprint itself on the photo, and then the quick flash of the flash will illuminate everything, only for a fraction of a second, imprinting the image of the entire room on the photo, in focus. After the flash has gone out, your shutter is still open. If you begin to move your camera, any dim light source present, such as a candle flame, sconce, light from a meter, or lit flashlight on a table, will continue to imprint itself. If you move to the side to take another photo, the light will appear on the image as horizontal, or possibly zig-zagging, streaks. If you begin to lower your camera as if to carry it at your side, then a vertical light streak will appear; this is why these streaks are frequently seen traveling upward in the photo, enhancing the belief that it is a spirit rising. This effect can also be present in conventional film cameras.

So, the mysterious light streak is explained, the case can be closed and we can go on with our lives, correct? In most cases, no. The next line of defense taken is usually, “but my camera doesn't do that.” In order to prove that the camera did, in fact, do that, an examination of the photograph's EXIF data must take place. EXIF (EXchangeable Image Format) data is information included within an image file from a digital camera that indicates resolution, shutter speed, focal length, and other settings associated with your camera. This data exists in its unaltered form within the original file of every digital photograph, uploading to Facebook or an image hosting website or even to an email from certain email addresses can alter or remove EXIF data. If you enhance, crop, or manipulate a photo in any way, the EXIF data will show that these changes occurred. It is best to present any altered photos with the original alongside, although, typically, we do not accept an altered photo as evidence. If a transfer of the image must take place, the best way would be the original, unenhanced version via a thumb drive or disc.

I am able to access the EXIF data for photographs on my computer by opening a photo, right-clicking on it, then selecting Properties. Within the window that opens are two tab selections, General and Summary. I select the Summary tab and then click on the button below that says Advanced and my EXIF data is revealed. There are also EXIF reading websites available; if you search “free EXIF data reader,” select one, and upload your photo, more information is revealed. If I examine the data from photos that I have taken with my camera in broad daylight, the shutter speed shown ranges from 1/318 sec. to 1/636 sec. A cloudy day on a porch brings it down to 1/101. A darkened room with NO flash brings the shutter speed down to 1/8. Flipping my flash on and taking another photo in that same darkened room brings the shutter speed to only 1/15 sec. As you can see, it is drastically slower than well lit conditions. We spoke to a team who agreed to examine light streak photos obtained during one of their investigations and they observed that their shutter speed in flash mode was a full two seconds. As they said, “Wow. That's slow.” That's slow, indeed.

If the next line of defense is then, “well, your streaks don't look exactly the same as mine...” then you know you are debating a topic with someone who will not listen to reason and your efforts should be abandoned. In light of all of this information, merely knowing your camera was experiencing slow shutter speed in flash mode should provide enough doubt to throw out the photo as evidence. Expecting exact duplication is unrealistic, there are many factors to take into consideration, the model of the camera, the variation of the shutter speed in flash mode from camera to camera, the light source causing the streak, the movement of the camera, the environment, etc. A reasonable duplication should be proof enough that we know what is occurring here, and it has nothing to do with the paranormal. Before showing us that photo or posting it on your website, look at your EXIF data. You may be surprised to learn that all you really have is evidence of a shaky camera!

Next Article: Blinking Flashlights