posted 06-12-2001 05:08 PM            

Lulu,

The roswell rods page used to have a message board. We tried to explain to
Jose what happens when insects fly in front of a video camera. The main
thing being that the closer an object is to the lens, the shorter the
distance it must travel to enter and exit the frame. Angular velocity is the
fancy term for it. The closer something is to the lens, the faster it
appears to be going. We had a long tussle over that and other issues such as
how some video cameras operate and whether they do or don't default to a
slower shutter speed with less light. Jose told everyone to use the "sports"
setting, but we said that the camera would only use the highest speed
possible for the available light, and that wouldn't necessarily be fast
enough to freeze motion. At any rate, the place where Jose filmed a lot of
his rods is called the cave of the swallows in Mexico, and swallows eat
insects. You can draw your own conclusions, but Jose took down the message
board during the discussions. Jose did some tests which were shot at
1/10,000sec shutter speed and insects were indeed frozen. None of his rods
films were ever shot at those speeds, however, as indicated by blurry
backgrounds and other blurry objects. The cave diver video was touted as a
high speed shot until we pointed out the motion blurred cave walls. I am a
hobby photographer and I always thought they were insects, particularly
after I saw the video of a swallow chasing a rod and keeping up with it. Sol
had a whole page which he called BUGRODS, but it seems to be down. He did a
lot of work and concluded that they were insects and their angular velocity
was causing them to look like rods. Also you have to remember that the video
is shown at 30 frames per second, regardless of what shutter speed it may
have been shot at. That is, each frame covers 1/30th of a second. Something
traveling only 10mph still travels around 6 inches per frame or 15 feet per
second.

As an example, suppose we set up two poles that are 20 feet apart. We set up
our camera so that the poles are lined up with the edges of the frame. An
insect traveling 20mph flies across the frame in between our 2 poles. 20mph
= 30 feet per second, so right away we know that we will have to be quick to
see this insect on the tape. It will cross the frame in 2/3 of a second and
will only be on 20 frames of the video at most. You would have to slow the
tape down to see it, even though it is only going a measly 20mph. If we zoom
in a little, we will have even less time to see it, because our frame width
is now smaller and the insect will appear on even fewer frames, as it has
less distance to travel to enter and exit the frame.

Regards,

LTC8K6

P.S. The high speed cameras that one guy set up were Redlake cameras from
Kodak, I believe. Sorry this is so long winded, but the many reasons for
motion blur are complex.

posted 06-14-2001 01:02 PM            

"Please know that the images & animations from "Sky~View 2000" were made with the focus always set to infinity & the zoom factor was moderate. The roof line in many scenes was 8 feet from the camera. The small tree top when present was 30 feet from the camera. One of the animations seems to clearly show a white object rising from beyond the 30 foot distant tree top. Birds in my digital recording look exactly like birds. Some insects were noted in this recording & their behavior was as would be expected of insects. Most if not all of the objects that I have presented are unlike any insects that I know of. Please note the clusters of small white objects in some of the animations. These are examples of a swarming that I saw that day. Dozens of these swarms were seen. All swarming that I saw were at least 100 feet from the camera. I have been an avid sky watcher for decades & this is the only day I have ever seen such swarming. They were easily discernable from the multitude of other activity going on by their very rhythmic motion. Magnetics & the orbit of an electron would always come to mind when seeing them.
StarGate-1 the TV show had some creatures that seemed similar. Spherical energy based life form. This show aired about 3-4 days ago on Dishnetwork. I will extract & send you some better examples of this as my time permits."

posted 06-14-2001 01:38 PM            

[Edited 1 times, lastly by Thermit on 06-14-2001]