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Ricky
SFN Die Hard
USA
4907 Posts |
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Dave W.
Info Junkie
USA
26022 Posts |
 Posted - 12/09/2004 : 20:36:16 [Permalink]
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Damn, I lost track of time. Because I was involved...
So I took the "before" frame, and ran a difference on the frame with the anomaly in it. Then I enhanced the contrast of the result, and discovered that the movement of the boat on the right, the movement of the clouds, and the changes in the play of sunlight on the water were dropping my contrast enhancements of the "thing" to pathetic levels. So, I cropped the photos in the middle, and did it all again, enlarging the results by a factor of two to better see the pixels.
Given that there are JPEG artifacts in the images, and the freaking trees are swaying in the breeze, Siberia and H. are probably correct: it's a bug, flying from upper left towards lower right, close to the lens, when the flash went off:
In this image, black indicates no difference in pixel values between the two images, while bright colors indicate large differences in pixel values.
Most of the "thing" is medium gray, while (if it's a bug) its butt is very bright. Don't know how many bugs have highly reflective butts and drab thoraxes and heads, but this may be one of them. The horizontal lines in its upper "wing" are probably just JPEG artifacts, as are much of the two horizontal bands of differences running the full width of this image. |
- Dave W. (Private Msg, EMail)
Evidently, I rock!
Why not question something for a change?
Visit Dave's Psoriasis Info, too. |
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H. Humbert
SFN Die Hard
USA
4574 Posts |
Posted - 12/09/2004 : 21:38:00 [Permalink]
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Nice job, Dave. It certainly looks like a fat-bellied moth in that high-contrast image to me. We might never know for certain, but light reflecting off a high-velocity, out-of-focus insect seems to be the most plausible answer.
Ricky, nice work testing your own theory. I wish I had that sort of initiative. I'm more of an "armchair skeptic," if you know what I mean. (re: lazy).
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"A man is his own easiest dupe, for what he wishes to be true he generally believes to be true." --Demosthenes
"The first principle is that you must not fool yourself - and you are the easiest person to fool." --Richard P. Feynman
"Face facts with dignity." --found inside a fortune cookie |
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way
New Member
USA
35 Posts |
Posted - 12/09/2004 : 21:42:20 [Permalink]
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| Pretty damn impressive all around and better than most of what I've been reading on the other forum. |
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Dave W.
Info Junkie
USA
26022 Posts |
Posted - 12/09/2004 : 21:47:37 [Permalink]
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What I was hoping for, H, was something else to "pop out" in the contrast-enhanced difference images, something even less obvious than the darkened trail of the bug (which must have been due to a longish exposure - note the extreme brightness of the sun-washed clouds - a fast bug, and the flash going off at the end of the exposure). But nothing came to light, so to speak. I'm talking something conclusive, like antennae or legs, or even the outline of something moving under the thing along the pier (which would have suggested something other than "bug").
No such luck. The object's symmetry and overall shape certainly do say "moth." Not nearly as exciting as I'd hoped. Oh, well. |
- Dave W. (Private Msg, EMail)
Evidently, I rock!
Why not question something for a change?
Visit Dave's Psoriasis Info, too. |
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Dave W.
Info Junkie
USA
26022 Posts |
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Ricky
SFN Die Hard
USA
4907 Posts |
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H. Humbert
SFN Die Hard
USA
4574 Posts |
Posted - 12/09/2004 : 23:08:23 [Permalink]
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quote:
Originally posted by Dave W.
...which must have been due to a longish exposure - note the extreme brightness of the sun-washed clouds - a fast bug, and the flash going off at the end of the exposure.
That was one of the things tripping up my bug theory, actually. Well, in all fairness Siberia was the first to mention that possibility, but I had been thinking along similar lines.
See, for a static, extended-exposure landscape shot, the guy shouldn't have been using a flash anyway, right? I mean, a flash wouldn't reach any farther than a few feet past the camera, when his subject was a waterfront hundreds of yards away. If he did use a flash, the only effect it would have is to light up any foreign detrius that drifted near enough, (which again, would be extremely out of focus being so close).
So, my lingering questions are: 1) Why would the guy use a flash in the first place? (The caption did say he was an amateur photographer, so it could have been a case of inexperience), and 2) Why was the flash set to go off at the end of the exposure? I don't know, is that even a normal thing for a camera to do? Because like you pointed out, the bug would have had to fly all the way across the open shot before being caught in the light bloom at the bottom.
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"A man is his own easiest dupe, for what he wishes to be true he generally believes to be true." --Demosthenes
"The first principle is that you must not fool yourself - and you are the easiest person to fool." --Richard P. Feynman
"Face facts with dignity." --found inside a fortune cookie |
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H. Humbert
SFN Die Hard
USA
4574 Posts |
Posted - 12/09/2004 : 23:14:54 [Permalink]
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quote:
Originally posted by Ricky
How close would this "object" (now thought to be a bug) have to be to appear in the picture that large? Then I guess I would compare this length to how fast a bug can fly and the shutter speed of the camera just to make sure that it is responsible for that grey streak.
Difficult to say. First we would need to identify what kind of bug it was, then we might be able to gauge distance. But I don't think the image is clear enough to allow for classification. |
"A man is his own easiest dupe, for what he wishes to be true he generally believes to be true." --Demosthenes
"The first principle is that you must not fool yourself - and you are the easiest person to fool." --Richard P. Feynman
"Face facts with dignity." --found inside a fortune cookie |
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Ricky
SFN Die Hard
USA
4907 Posts |
Posted - 12/09/2004 : 23:29:11 [Permalink]
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<blockquote id="quote"><font size="1" face="Verdana,Arial,Helvetica" id="quote">quote:<hr height="1" noshade id="quote">quote:Originally posted by H. Humbert
<blockquote id="quote"><font size="1" face="Verdana,Arial,Helvetica" id="quote">quote:<hr height="1" noshade id="quote">quote:Originally posted by Ricky
How close would this "object" (now thought to be a bug) have to be to appear in the picture that large? Then I guess I would compare this length to how fast a bug can fly and the shutter speed of the camera just to make sure that it is responsible for that grey streak.
[/quote]Difficult to say. First we would need to identify what kind of bug it was, then we might be able to gauge distance. But I don't think the image is clear enough to allow for classification.
[/quote]
Could we not try it for different bugs? For example, lets say it was a moth. A moth is A millimeters long. That would lead to the moth being B millimeters away from the camera. A moth also has an average speed of C, we would expect to see is D.
Of course, both moth size and speed of flight have a chance to be significantly off to the point that it would create false results, either positive or negative, so doing so would most likely be a waste of time.
That, and I'm pretty sure its not as easy as I made it seem in the first place to do the math.
Edit:
Whats going on with the quote button? Is it not working? Twice now I've pressed "Reply to post" and it not work right.
Edit #2:
I'm going to leave my previous edit up there just because I find it extremely funny. "it not work right" was supposed to be "it hasn't worked correctly" |
Why continue? Because we must. Because we have the call. Because it is nobler to fight for rationality without winning than to give up in the face of continued defeats. Because whatever true progress humanity makes is through the rationality of the occasional individual and because any one individual we may win for the cause may do more for humanity than a hundred thousand who hug their superstitions to their breast.
- Isaac Asimov |
| Edited by - Ricky on 12/09/2004 23:33:22 |
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Stargirl
Skeptic Friend
USA
94 Posts |
Posted - 12/13/2004 : 18:21:24 [Permalink]
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If you look at the plants on the bottom left of the image there is no indication that they were illuminated by a flash.
And if you look at the surface of the water to the right you can see individual wave crests which means the exposure can't be very long.
The exposure was probably less than a second or the crests would have been blurred.
I have to go along with the bug theory but I'm thinking more along the lines of a lightning bug.
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If God did not exist, it would be necessary to invent him - Voltaire |
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Randy
SFN Regular
USA
1990 Posts |
Posted - 12/13/2004 : 18:58:54 [Permalink]
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Nice work Dave W. Siberia, and H.
Stargirl, with you mentioning about possibility of no flash, I did a check on the APOD 'before' image with saving it to file. I checked the photo file for buried EXIF information, and it was there. Flash -was- used on both images. See the camera recorded data below.
Here it is for the 'before' image:
Make - Canon
Model - Canon PowerShot G3
Orientation - Top left
XResolution - 180
YResolution - 180
ResolutionUnit - Inch
Software - ACD Systems Digital Imaging
DateTime - 2004:11:25 15:23:11
YCbCrPositioning - Centered
ExifOffset - 223
ExposureTime - 1/20 seconds
FNumber - 5.60
ExifVersion - 0220
DateTimeOriginal - 2004:11:22 18:53:07
DateTimeDigitized - 2004:11:22 18:53:07
ComponentsConfiguration - YCbCr
CompressedBitsPerPixel - 3 (bits/pixel)
ShutterSpeedValue - 1/20 seconds
ApertureValue - F 5.60
ExposureBiasValue - 0.00
MaxApertureValue - F 2.20
MeteringMode - Multi-segment
Flash - Flash fired, auto mode, red-eye reduction mode
FocalLength - 9.09 mm
UserComment -
SubsecTime - 3682872
FlashPixVersion - 0100
ColorSpace - sRGB
ExifImageWidth - 2272
ExifImageHeight - 1704
InteroperabilityOffset - 1587
FocalPlaneXResolution - 8114.29
FocalPlaneYResolution - 8114.29
FocalPlaneResolutionUnit - Inch
SensingMethod - One-chip color area sensor
FileSource - DSC - Digital still camera
CustomRendered - Normal process
ExposureMode - Auto
WhiteBalance - Auto
DigitalZoomRatio - 1.00 x
SceneCaptureType - Landscape
===========================================
and for the 'after' image...
Make - Canon
Model - Canon PowerShot G3
Orientation - Top left
XResolution - 180
YResolution - 180
ResolutionUnit - Inch
Software - ACD Systems Digital Imaging
DateTime - 2004:11:25 15:20:49
YCbCrPositioning - Centered
ExifOffset - 223
ExposureTime - 1/20 seconds
FNumber - 5.60
ExifVersion - 0220
DateTimeOriginal - 2004:11:22 18:52:52
DateTimeDigitized - 2004:11:22 18:52:52
ComponentsConfiguration - YCbCr
CompressedBitsPerPixel - 3 (bits/pixel)
ShutterSpeedValue - 1/20 seconds
ApertureValue - F 5.60
ExposureBiasValue - 0.00
MaxApertureValue - F 2.20
MeteringMode - Multi-segment
Flash - Flash fired, auto mode, red-eye reduction mode
FocalLength - 9.09 mm
UserComment -
SubsecTime - 3420984
FlashPixVersion - 0100
ColorSpace - sRGB
ExifImageWidth - 2272
ExifImageHeight - 1704
InteroperabilityOffset - 1587
FocalPlaneXResolution - 8114.29
FocalPlaneYResolution - 8114.29
FocalPlaneResolutionUnit - Inch
SensingMethod - One-chip color area sensor
FileSource - DSC - Digital still camera
CustomRendered - Normal process
ExposureMode - Auto
WhiteBalance - Auto
DigitalZoomRatio - 1.00 x
SceneCaptureType - Landscape
Edited to shorten EXIF info
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"We are all connected; to each other biologically, to the earth chemically, to the rest of the universe atomically."
"So you're made of detritus [from exploded stars]. Get over it. Or better yet, celebrate it. After all, what nobler thought can one cherish than that the universe lives within us all?"
-Neil DeGrasse Tyson |
| Edited by - Randy on 12/13/2004 19:04:18 |
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