Strange streak discussion: 2004 Dec 7 APOD

[Guest]

Re: wombat, "So I think my question still stands."

Dear wombat:

I think the best thing for you to do would be to combine your thoughts with
the "Engineer in Canada" into one larger, incoherent paragraph, so that it
would be easier to pass over.

[wombat]

Uhh, "guest", I was replying to Victorengel's comment, and he has certainly had no difficulty understanding anything I've said so far.

[Guest]

It appears, and I'm open to comment, that you are trying to bait
victorengle, a most reasoned voice (among others here,) into a
nonsensical argument just to waste his time.

And yes, to me, it is mostly incoherent, or irrelevant.

[Guest]

"wombat/Engineer in Canada?"

"The easiest thing too say is that the complex appearance is due to
warping of the insect wings under load, so that they are non-planar, and hence give unusual reflections. I see a parallel in this argument to the
hoax theory, in that you could probably take almost any arbitrary wing
shape, bend it into to something reasonable according to wingbeat phase,
flight load ect; then orient the insect, camera, and flash so as to get
exactly what we see here. The light is thus refracted due to the smoke
and looks like it might be sparks which is impossible because sparks
don't have a pattern to the, they fly all over the place, and nothing is
being ejected under or to the left of the pole, it looks pretty homogenious with a heavier light concentration at the light and a more disperse still
homogenious above the light bulb of the pole.

... the smoking gun... (tough to proofread, though.)

[wombat]

Well, Guest, your postings have had the desired effect: you've confused and terrified me completely.

Victor has shown he can be merciless when required (eg, his "tripod" comment). I'll now await his response (which could be to ignore everything you and I have said).

[victorengel]

Interesting that I seem to be the topic of recent conversation. I hope this isn't permanent. I assume that your "when required" grants that my tripod statement was not out of line. It seemed to me that a moment's reflection made it clear that a tripod was used.

But to answer your post...

Victor, whilst I accept your comment that

the camera's strobe fires not at an instant in time but over a segment of time

, to paraphrase you, so what? I can't see how a simple integration/blurring would give the complex wing pattern that we have.

I'm not sure how to answer this because I'm not sure where you're seeing complexity. The wing pattern I see doesn't appear to me to be particularly complex. One thing I have trouble with, for example, is separating the jpeg artifacts from the complexity in the image. If we are to remove everything that could be jpeg artifacts, are we not left with a relatively simple pattern?

As has been discussed, most of the light from an electronic flash is discharged over a millisecond or so. Even at 200Hz, the top end of the wingbeat frequencies discussed in this forum, 1ms would not give a lot of blur.

A millisecond is likely close to the maximum duration of the flash. I think there is evidence that the strobe fired for a much briefer time, although I cannot demonstrate it. On the other hand, the 200Hz figure comes from the assumption that we are dealing with a bee or something of similar size. There are insects with much faster wingbeats, the fastest being up to 60,000Hz. I don't believe for a minute we are dealing with such a midge. On the other hand, I don't think a strong case has been made yet giving a lower bound for the insect size. Perhaps someone posted something to this effect and I just missed it.

I would consider a different line of reasoning. We evidently have an approximate body size in relation to the length of the trail. Given the ratio of the trail length to the body size, there is probably a narrow range of frequencies that correspond to normal insect flight patterns. Obviously we are not looking at a hovering insect, or we wouldn't have a trail. And considering the short 1/20 second exposure, it's reasonable to assume the insect is at cruising speed or comparable. We might look at a variety of rod pictures to get an idea of what percentage of a wing flap cycle we can expect to be captured by the flash. Better yet, given the frequency analysis some pages back that showed something like 11 or 12 possible flaps over the length of the trail, we might assume a wavelength of a flap. We could then look at the blur of the insect body and determine how much of the blur is from being out of focus and how much is motion blur. The amount of motion blur would be a confirmation of the duration of the strobe. I think this was guessed at, but I'm unaware of anyone having actually measured it. The result, compared to the 11 or 12 wing flaps should produce the percentage of a full cycle that was captured by the flash. My gut instinct puts it at about 10% or so of a full cycle. More work is required to check this, and I no longer have the time to spend on it.

Finally, since our view of the insect is apparently mainly head/tail on (rather than side on), I would expect that the amount of flash blur would be more or less directly proportional to distance from the body - a fan shape, if you will. I don't see that.

This doesn't follow. Your statement assumes that an equal portion of the wing is being reflected into the camera throughout the duration of the strobe. Such is not the case. Only that portion of the wing that happens to be at the right angle at the right time will be imaged. As the time elapses, the part of the wing being image changes (moves to a different part of the wing, but not necessarily a different point in space).

If you have one available, I suggest getting out a fan. Any household fan, especially one you can manually turn while the power is disconnected would be ideal. The spinning blades of the fan represent the wings of the insect.

Turn the fan on so that the blades of the fan catch the glint of a light source. You will probably notice that as the fan is spinning, you see an arc of light reflected in the spinning blades. The shape of this arc does NOT match the shape of the blades, nor does it match the trajectory of the blades. A similar thing is happening with the insect wings, except that the insect wings change orientation in a different way (back and forth in a sort of figure 8 shape rather than a circular pattern).

[wombat]

Gee, maybe guest is right, and I am being too difficult to understand.

Victor, your tripod comment was appropriate.

I accept your fan argument; it was what i was thinking about, but you phrased it better than I did.

The only place where I'm seeing complexity is that there appear to be two entirely different sets of wing patterns. There are the ones that stick out at say 1 o'clock and 7 o'clock from the yellow blob BUT don't actually meet the yellow blob. These do look like vanilla "main spar" long wings; and yes you are right they are not particularly complex in themselves.

What causes me trouble is the arc semi-circling the yellow blob to the right, from say 2 o'clock to 6 o'clock. This to me at least looks "real"; ie, doesn't look like a jpeg artifact. It certainly is on the various processed images. I have great difficulty in seeing this arc as belonging to the main spars. I mean the arc meets the long wings at ninety degrees; this seems too extreme to be modelled by just one pair of wings, no matter how you contort your fan blades.

All that - and the dragon fly - made me think about a four winged insect. Making this semi-circle as a separate pair of wings (ie, in your analogy, another pair of fan blades but with a different "twist") seems to make a much better model.

The bit that you said doesn't follow is now irrelevant. It would only have made sense in the context of a long (more than 1ms) flash, which at the time is what it seemed to me you were talking about; and yes, for a sub msec flash it does indeed not follow.

[victorengel]

What causes me trouble is the arc semi-circling the yellow blob to the right, from say 2 o'clock to 6 o'clock. This to me at least looks "real"; ie, doesn't look like a jpeg artifact. It certainly is on the various processed images. I have great difficulty in seeing this arc as belonging to the main spars. I mean the arc meets the long wings at ninety degrees; this seems too extreme to be modelled by just one pair of wings, no matter how you contort your fan blades.

What makes you think the 2 to 6 oclock pattern is wings? To my eye, that looks more like the fuzzy portion around a bee's thorax.

[wombat]

Well, if it's not the smaller rear wings, my four wing theory goes out the window. LOL.

I guess this is a matter of perception. This struck me as wings from the very first "bug" posting and the thought has stayed with me since. I guess because it's the same general brightness and colour as the long wings.

Victor, I just can't see it as the thorax. Inside that arc seems to be about the same brightness and colour as the rest of the water in the immediate area. To me that would make the thorax not only transparent but also totally non-reflective of the flash, which seems highly improbable

And I think that others see it the same way. Think about all the posts that talk about the "flash" being disconnected from the "smoke". They're saying what I'm saying, but in a different context.

[George]

1. Assuming the insect is really at a sharp angle to the camera, could the anglebe due to its being blown by a gust of wind? If so, it will be hard to identify, from just the length of the streak, the insect species and (consequently) the no. of flaps of its wings it would be able to complete.
2. If the main motive power within the frame is wind, could the wing flaps cause the path to curve towards the camera?
3. If so, how likely is it that these 2 forces would still produce a path that looked straight as viewed from the camera?
2. Could the bee with the yellow belly suggested earlier reflect this much light?

[Ernst Lippe]

Another argument that Victor did not mention in support of the theory that the
image of the "wings" is caused by a reflection and not by a full image of the
wings themselves, is the odd position of the wings. After all, it seems strange
that we can see one wing that points up and one wing that points down, if the
bug indeed follows the path of the streak. But this is completely
understandable if we assume that we can only see the reflection of the wings
when there are in a specific orientation. See for example the following
"flying rods" picture where the wings also have a very strange orientation:
http://www.opendb.com/sol/morerods.htm

Victor, I just can't see it as the thorax. Inside that arc seems to be about the same brightness and colour as the rest of the water in the immediate area. To me that would make the thorax not only transparent but also totally non-reflective of the flash, which seems highly improbable

There is nothing strange about the fact that it looks transparent. Remember
that the bug was only in that location for a very short period, the rest of
the time the camera will simply record the background. The bug is transparent
everywhere, even in the bright spot we can still see features from the
background.

It is somewhat remarkable that this blob is darker in its center. There are
several possible explanations. Many insects have hairs, and in general such
hairs will reflect light better when you look at them sideways than when you
look in the direction that the hairs are pointing. Another possible
explanation could be that the insect is semi-transparent (that seems true for
the non-flying forms of the white ant, and it might hold as well for the
flying forms) in that case most of the light will be dispersed by the "skin"
of the insect. Because most of the surface of a sphere is visually located
near the edge of the sphere that could also explain the fact that it appears
darker near the center. Yet another explanation is that it is simply an
optical phenomenon due to the fact that the bug is also severely out of
focus. If you have ever used a microscope you will probably have noticed that
unfocused objects can have very strange shapes.

And I think that others see it the same way. Think about all the posts that
talk about the "flash" being disconnected from the "smoke". They're saying
what I'm saying, but in a different context.

There is also a simple explanation why the smoke is disconnected from the
"flash". When you look at the amount of light that is emitted by a flashlight
there is a period when it rises from zero to its maximum and after that
another period where it falls back again. So when you examine the streak near
the insect you expect a gradual transition from dark to the maximum intensity
where the insect that has been exposed to the maximal flash. So somewhere in
between there must be an area where the intensity of the reflected flash light
is equal to the "darkness" of the trail and in that area we can neither see
the trail nor the reflected flash light.

[makc]

I'm not sure how to answer this because I'm not sure where you're seeing complexity...are we not left with a relatively simple pattern?

I made some simple enhancements on this image. Don't know if it would help you to see complexity, or jpeg artifacts.

[Minbari]

I have seen something similar to this with the same conditions during a sunrise or sunset (usually a sunset).

To me it looks like the opposite of a light streak beaming through the clouds. On the odd occasion when the sun is setting and there is a majority cloud cover the light bounces of the ionosphere and bounces back to the top of the clouds creating a glare in the clouds.

In this glare I have seen streaks of shadows between the light that for some reason (probably an optical illusion) stand out due to the glare.

When there isn't so much cloud cover one can see the light and dark streaks.

Was the camera film based or CCD?

[Numbat]

Back after two weeks holiday.
I wish to take issue with the someone (about 50 pages back) who made the very negative remarks about "amateurs", then posted some even more negative synonyms allegedly from a dictionary.

Thus, an amateur is someone who does something for the love of it, as distinct from being paid for it. There is no intrinsic negativity in the definition at all. I am amazed that this supposed dictionary had these alleged synonyms in it at all. In fact I don't believe it at all.

You are indeed an amateur.
Try typing "amateur definition" in google and one of the first results you will get is:
http://www.hyperdictionary.com/dictionary/amateur
Note also, Antonyms: pro, professional

Is this proof enough, or does the answer have to involve a flying insect to be believed by you?

[Numbat]

Here's another definition you may enjoy.

Wombat:
1. Waste Of Money, Brains, And Time.

Problems which are both profoundly uninteresting in themselves and unlikely to benefit anyone interesting even if solved. Often used in fanciful constructions such as "wrestling with a wombat".

So apt for this discussion.

[victorengel]

Victor, I just can't see it as the thorax. Inside that arc seems to be about the same brightness and colour as the rest of the water in the immediate area. To me that would make the thorax not only transparent but also totally non-reflective of the flash, which seems highly improbable

That doesn't make the thorax transparent. That makes it black, or at least very dark. Honeybee thoraxes are indeed very dark and are covered with very fine hairs. These hairs reflect the strobe when they are perpendicular to the strobe. Look at these two pictures for example. The bottom one is better than the top because it's obviously a flash photo. The other one probably is, too, but with the flash separated further from the camera.

[victorengel]

Look at this picture of a bee in flight. The picture was taken with ambient light and flash. The flash was short enough to freeze the wings when they were near the highest position. However, look at the wings over the rest of the flapping cycle that's captured. You can see the near wing all the way to the bottom, but the far wing is only obvious near the top. That's because the orientation of the wings is such that the near wing reflects more light toward the camera than the far wing. If just the wing reflections were taken by themselves, it would look like this bee is in banking flight when in actuality it is quite level.

[wombat]

Ok, Ok, very good data and explanations. I see that there is indeed no need to postulate a second pair of wings. That last bee photo is particularly convincing. I have a different explanation for the apparent steep banking angle. I think that both explanations are still valid, but as numbat says, that was probably never important.

PS. Victor, when you were talking about thorax, did you perhaps mean abdomen? The bottom end?

[victorengel]

PS. Victor, when you were talking about thorax, did you perhaps mean abdomen? The bottom end?

No. The wings and legs are attached to the thorax. It is the thorax I was referring to. Also the abdomen has a longer aspect ratio than the thorax. Here I've composited two pictures to show a possible alignment between a known bee photo (I mirrored it) and the anomalous image. See how the wings attach to the thorax? I also note that there is a specular reflection at the center (approximately) of the thorax. The anomalous image also apparently has a brighter spot in the center of the ring which I'm suggesting could be the outline of the thorax. The resolution is at the same level as the jpeg compression, though, so I don't put much weight to that.

[wombat]

You did very well to find an actual photo with the right ambient/flash lighting.

But Victor, haven't you just contradicted yourself here? Yes, the wings attach to the thorax, which is my semi-circle. You can see the attachment point quite clearly. The yellow blob is then the abdomen. The bee is much more head-on in the anomalous image than it is in your photo.

[Guest]

Dear wombat:

For Christ's sake it's a bee; enough.

[Guest]

"but as numbat says.."

"numbat," dumbat, is a play on words.

Is this a "special" forum?

[Leyshon]

I'd like to update my previous theories:
Now I'm convinced that this is a United States military weapons
demostration of its new microwave weapon capabilities.
I don't think this beam weapon was fired from an aircraft some kilometers off.

Some quick Google research will inform you that a high energy microwave beam, traveling through the atmosphere, would polarize the air through which it travels. In otherwords the air would appear darker !

The mirowave weapon would be used many towards the disruption of electrical devices.

I refer all interested to :

http://www.aviationnow.com/avnow/news/c ... 004dir.xml

[Guest]

'I think that both explanations are still valid, but as numbat says, that was
probably never important."

Dear wombat/dingbat/dunmbat/whatever:

Wombat said what?

[wombat]

Yeah, I think some of you guys are right: it's a bee or bee-like critter, and any more discussion is ... what did numbat say ... "wrestling with wombats". I like that phrase. I'm sure my wife will too. LOL.