The light is in our eyes...

A camera does not detect time at all, unless it is a video or a motion picture camera, in which case the shutter speed and frame rates come into play. The saccades of our own eyes replace the shutter or frame rate for motion.

This is a valid, if obscure, observation.
 
For those who do not understand QQ's "Ol Roemer" reference, Roemer was the astronomer who surmised the speed of light from an astronomical observation of the timing of the orbit of a moon (Io) of the planet Jupiter, using the diameter of the Earth's orbit in diametrically opposed seasons to perform the necessary timing measurements. The difference observed would have been about 2 astronomical units, or about 17 light minutes. That's how much the period of Io's rotation / eclipse of Jupiter's moon Io would have been delayed.

From this experiment, Roemer concluded that the speed of light was considerably greater than one Earth diameter in one second, but because the radius of the Earth's own orbit had not been agreed upon at the time, that was as much accuracy of the speed of light Roemer was able to manage.

This same method was later used to determine the eccentricity of Earth's own orbit, no doubt.
 
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Roemer was of course able to surmise the speed of light from spatial timing considerations.

Saccade duration is about 200 milliseconds, corresponding to a frame rate of about 5 Hz. This rate makes sense, in terms of optic neuron synapse prop delays. No wonder slower frame rates for video and movies are an easy illusion.

The speed of visual signals in the optic nerve is proportional to light intensity, which allows some pretty interesting physics classroom demonstrations with pedulums and sunglasses held in front of one eye. This probably explains why slower frame rates for movies are mildly annoying also. If one scene is lighter and the next one is dark or vice versa, your visual system will detect this as flicker.

Anything else vision related we haven't already discussed in the thread?
 
Quantum Quack said:
my opinion stated in this fora would be inappropriate.
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Right. So drop the metaphysical stuff and just deal with the actual physics stuff.

To do that, you'll have to accept, for the sake of discussion that, what we see is what we see.

Now, the OP is about where is the light that is on our eyes.
 
danshawen said:
A camera does not detect time at all, unless it is a video or a motion picture camera, in which case the shutter speed and frame rates come into play. The saccades of our own eyes replace the shutter or frame rate for motion.

This is a valid, if obscure, observation.
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I agree, and if I may offer a minor addition.
A camera has two modes of controlling incoming light for proper exposure. Lens aperture and shutter-speed.
A wide aperture allows for fast shutter speed to "freeze" the picture, but you lose depth of field.
Slow shutter speed allows for a small aperture, which increases depth of field, but at slow shutter speeds a moving object will be recorded as *blurry*, unless you pan the camera to keep the moving object in the center of the frame. But then the background becomes *blurry*.
OTOH. if the camera is in motion, a fixed object will also show a blur, unless a fast shutter speed is used.

In any case a camera doesn't care about the length of time the light has traveled before it reaches the lens. Nor does the eye. They both rely on available lumens *present* at time of exposure or perception.
Motion perception is the process of inferring the speed and direction of elements in a scene based on visual input. Monocular vision, or vision from one eye, can detect nearby motion; however, this type of vision is poor at depth perception.
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luminous flux is weighted according to a model (a "luminosity function") of the human eye's sensitivity to various wavelengths
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Seattle said:
That has nothing to do with the questions you've brought up anymore than Write4u bringing up Special Relativity.
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I merely included it, because at high speeds the Doppler effect alters the wave length of the incoming light from approaching or receding emitters. Blue shift, Red shift.
It's a minor point, but it IS science and related to vision (observation)
The relativistic Doppler effect is the change in frequency (and wavelength) of light, caused by the relative motion of the source and the observer (as in the classical Doppler effect), when taking into account effects described by the special theory of relativity.
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Am I too far out in left field here?
 
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Write4U said:
I merely included it, because at high speeds the Doppler effect alters the wave length of the incoming light from approaching or receding emitters. Blue shift, Red shift.
It's a minor point, but it IS science and related to vision (observation) Am I too far out in left field here?
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Yes. :) There is nothing related to Special Relativity going on here. We aren't talking about space expanding and travelling at close to the speed of light. We're just talking about light itself and SR doesn't apply in any meaningful way.

That's why no one uses the math of GR when classical Newtonian physics will do. If you aren't talking about vast distances and/or speeds approaching the speed of light the differences are too small to be significant (in general). Yes, there is GPS but we aren't talking about GPS now. :)
 
DaveC426913 said:
Right. So drop the metaphysical stuff and just deal with the actual physics stuff.

To do that, you'll have to accept, for the sake of discussion that, what we see is what we see.

Now, the OP is about where is the light that is on our eyes.
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you really need to make up your mind...

What we see is what we see (objective)
or
What we see is what we interpret from the data entering our eyes (metaphysically subjective)...which is it?
 
Quantum Quack said:
you really need to make up your mind...

What we see is what we see (objective)
or
What we see is what we interpret from the data entering our eyes (metaphysically subjective)...which is it?
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No. That's for a metaphysical discussion in another forum.

Here, physics works the way mainstream physics says it does. You'll have to frame this argument in those terms, and start a new thread about the metaphysics elsewhere.

You need to make up your mind which discussion you want to have, and where.
 
Seattle said:
We know what the deal is. QQ doesn't want to deal with the other crank in the non-science forums so he traps himself in here where he can't really express himself as it don't involve any science.

So, he just continues to pl

With over 9,000 posts, you've been around here long enough to know that the answer to that question is "no". :)
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Don't worry, me and origin go way back. Well before delta t=o then d=0 or 0.999... =1 discussions... hee hee
 
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