Lens effect, or Aliens disturbing the circles of Archimedes?

Kyriakos

Kyriakos

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Not a very sensational thread title, i hope :mischief:

Anyway, it is about the following:

I read in some other game-related forum of a lens effect "shot routinely in meadows as video cameras are aimed up into random parts of the skies" which strangely (?) turns a flying insect into an image that looks mostly like an Archimedian invention...

Lens effect:

clip_image0042.jpg


Archimedian Screw:

Archimedes_screw.JPG


Rather peculiar distortion- to say the least. Wondering if (in the case that is what is going on) we know the optical equations supposedly producing this effect. The thread mostly was made so as to ask about the lens properties, and any possible paper on this highly interesting effect on the screens there.

*

Alternatively those are aliens that are harvesting stuff on the air, using their version of this Archimedian device :yup: I suppose his circles had to be disturbed, so that they would have him back to the mothership :)
 
Just looks like motion blur to me. Insects zip along really fast and beat their wings at a very high rate, so even a relatively short exposure will capture them moving and beating their wings a few times and blur the whole thing out into a line with oscillatey wing flanges. That's my explanation anyway.
 
Manfred Belheim said:
Just looks like motion blur to me. Insects zip along really fast and beat their wings at a very high rate, so even a relatively short exposure will capture them moving and beating their wings a few times and blur the whole thing out into a line with oscillatey wing flanges. That's my explanation anyway.
Click to expand...

Ok, but that is rather too symmetric to be merely termed "motion blur"? It would be like having a regular dodecahedron presented as a blur of some ant or something :)
I am not saying it has to be not a lens effect, but i am curious as to the optic/light dispersal/lens properties which could cause this be the lens image of a flying insect.
 
I don't see the problem. Flies have symmetrical wings that they flap/beat in a regular oscillation. Time lapse that and obviously you get something symmetrical and regular.

And it isn't an optical effect or a lens effect, it's a passage of time effect.
 
^Could be, if the camera is set to capture stuff only if enough movement in front of it triggers its activation.
It still is a nice image, and one that clearly (at any rate) does effect the object even in such a time-lapse, cause afaik flies are not all diaphanous ;)

But the image could be diaphanous as a diophantine ( :( ).
 
No, those are just Sky Hydroponics Labs without their greenery. Not sure how they look like Archimedes' screws, especially with the lack of spiraling.
 
SS-18 ICBM said:
No, those are just Sky Hydroponics Labs without their greenery. Not sure how they look like Archimedes' screws, especially with the lack of spiraling.
Click to expand...

Sky hydroponics labs does sound legit, ok.

As for spiraling, well, just switch the image to the analogous one in a spiraling plane. I mean use your head ;)

(ps: the Archimedian screw is a helix system which has the end of causing a substance - eg liquids like water - to rise up in the helix-based construction when its end is set to move by simpler methods- ie wind power or actual manual labor. By itself it is not a spiral, at least not in the way we see it as an object in 3d space)

http://en.wikipedia.org/wiki/Archimedes'_screw

From that wiki link said:
Archimedes' screw consists of a screw (a helical surface surrounding a central cylindrical shaft) inside a hollow pipe. The screw is turned usually by a windmill or by manual labour. As the shaft turns, the bottom end scoops up a volume of water. This water will slide up in the spiral tube, until it finally pours out from the top of the tube and feeds the irrigation systems. The screw was used mostly for draining water out of mines or other areas of low lying water.
Click to expand...
 
Anything can look like anything if someone uses their head enough.
 
Flying rod, right? ;)
 
^That is their less than technical name, yes :) Also i now read that they are not the result of time-lapse camera capture, but something about the lens set to a specific distance (far horizon-related i suppose).
 
That's just the screen cursor for God's mouse.

Remember reading about the 50 dead cows killed by lightning under that farmer's tree the other day?
 
Okay... so nothing in this thread is serious right? I've stumbled into some weird game...
 
Huh. So an Archimedian Screw is an auger. Learn something new everyday!
 
Leonel said:
http://en.wikipedia.org/wiki/Rod_(optics)

/end thread
Click to expand...

I read the whole three paragraphs (sic) of that nice wiki article :) It does not provide the science behind the actual optical effect, -the paragraphs of the "analysis" are statements without info on the science itself- which was what i thought was clear i asked about. /end post :mischief:
 
Optical effect = time lapse of insect moving and flapping wings.
 
If an insect flaps it wings 150 times per second, and a camera is running at 25 frames per second, then you will record six flaps in one frame. Because the sunlight hitting one particular spot on the camera is obstructed by the insect for a shorter time than it takes for one frame, the insect appears to be translucent. And that s what you see in the picture.
 
uppi said:
If an insect flaps it wings 150 times per second, and a camera is running at 25 frames per second, then you will record six flaps in one frame. Because the sunlight hitting one particular spot on the camera is obstructed by the insect for a shorter time than it takes for one frame, the insect appears to be translucent. And that s what you see in the picture.
Click to expand...

+0,8

So why does the camera capture this specific pattern? In other words: can you give some detail on why the flow of the move seperates the wing span in this particular manner of the pic in the OP? Since that is what i asked about, due to the creation by effect of a nicely symmetric image with (apparently) a stable degree of the 'movement' progression angle of the insect (in your account it is all in one point of movement captured with a delay due to the smaller frame rate of the camera). The camera is immobile. The insect by that account only appears before it for an instant. I am asking of an elaboration on the optical properties, so as to gather why the optical effect produced would not have the consecutive images appear at less continious and less progression-like manner, but instead in the straight-line which seemingly is produced in the above pic.
 
I'm pretty sure you've been given full and complete answers about 4 or 5 times now and are simply not grasping it.
 
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