Spinner strobing as a "Bird Strike Countermeasure"

Mxsmanic wrote in
:

Maxwell writes:

Seems I have heard the 16 cps is all that is required for movies to
appear continuous.

Motion pictures use 24 ips, repeated once,


Blah blah, cut and paste boi does it again.

Boring.

Bring out a sockpuppet again! That was fuuuun!


Bertie

Mxsmanic wrote in
:

Roger (K8RI) writes:

At cruise RPM that effect would be completely lost. There's not a
bird or human alive that can discern stroboscopic effects of more
than a couple hundred cycles let alone over a 1000. Most of us can't
even discern 60 cps.

Birds have much better vision than human beings, and I don't believe
anyone has tested their ability to discern stroboscopic effects.

What using your parakeet as a wing man now in combat sim games?



Bertie

"Mxsmanic" wrote in message
...
And the front fan on a turbofan is turning at around 40-50 revolutions per
second, not
thousands.

My phonograph turns at either 33-1/3 or 45 RPM, which is just as relevant to
this conversation as your mention of turbofans.

In article ,
says...


Visual perception is funny and complex.

black & white films were 16 frames/second.
Color films are 24 frames/second


The frame-rate was increased from 16 to 24 at the introduction of sound (not
color). The increased linear speed was desirable to improve fidelity of the
analog optical soundtrack on the film. In either case, 24 or 16 FPS, each image
is projected three or two times (respectively) to produce an effective rate of
48 - this was done to avoid perception of flicker.



Also, the eye -- and brain -- 'notices' things that are too fleeting for
conscious identification. Google 'subliminal' advertizing -- IIRC, lab
tests showed that injected imagery with a duration of only a few milliseconds
had 'measurable' effects.



Oh NO! Not Vance Packard and the "Hidden Persuaders"!!

"Airbus" wrote in message
...
In article ,


The frame-rate was increased from 16 to 24 at the introduction of sound
(not
color). The increased linear speed was desirable to improve fidelity of
the
analog optical soundtrack on the film. In either case, 24 or 16 FPS, each
image
is projected three or two times (respectively) to produce an effective
rate of
48 - this was done to avoid perception of flicker.


Anyone know off hand what the frame rate was for home movies (8mm)?

I wonder about doing the candy stripe spiral on them, or painting the blades different colors...


The candy stripe spiral on the spinner was a recognition thing, the
Germans started doing that in the summer of '44. The Japanese did
something similar thru the war years by painting the inboard leading
edge of the wing yellow. Quick recognition by your comrades in a
dogfight when head on...

This is the first I've heard of the 1/3 and 2/3's strobe effect, I
thought it was also for recognition...Maybe I'll try it on my 172...

-Ryan

U.S. TV is 60 fields/second, European is 50/second.

And it takes two interlaced fields to make a frame, therefore US
broadcast TV standard (NTSC) is actually only 30 frames per second.
Europe's PAL and SECAM standards are both 50 interlaced fields per
second, yielding 25 actual frames per second.

"Airbus" wrote in message
...
In article , says...


Hence the reason an aircraft propeller will
appear to be revolving slowly backwards at times.

Not when being observed directly. That only happens in movies and video
due
to the interaction between the imaging rate and the rotation rate of the
propeller.

Wrong again you clueless twit.



No, he is right this time.

No he isn't.

"Airbus" wrote in message
...
In article , says...



"Airbus" wrote in message
...
In article , says...


Hence the reason an aircraft propeller will
appear to be revolving slowly backwards at times.

Not when being observed directly. That only happens in movies and
video
due
to the interaction between the imaging rate and the rotation rate of
the
propeller.

Wrong again you clueless twit.



No, he is right this time.

No he isn't.


Wellllllllll..............
The world is listening . . .


Indeed.

In rec.aviation.piloting Airbus wrote:
In article , says...



"Airbus" wrote in message
...
In article , says...


Hence the reason an aircraft propeller will
appear to be revolving slowly backwards at times.

Not when being observed directly. That only happens in movies and video
due
to the interaction between the imaging rate and the rotation rate of the
propeller.

Wrong again you clueless twit.



No, he is right this time.

No he isn't.


Wellllllllll..............
The world is listening . . .

When observed directly under artifical light that "flickers", the most
obvious being a strobe light, but there are other types of artificial
lights that have flicker.

--
Jim Pennino

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