How we see objects

[saor]

I'm having a brain-freeze here.

My initial question was how the light that reaches our eyes remains cohesive in a way that allows us to see the defined edges of an object. If I'm outdoors and light is coming from many directions and reflecting off an apple to reach my eye - it feels like I should get a hazy perception of the apple because it seems strange that wherever I stand, I'm in the right place to receive a cohesive 'bundle' of light representing the apple. Ugh.

Anyway.

It's maybe easier if I ask the question like this:
If I have a focused source of light that lights up some detail on a screen - how do I perceive that detail on the screen if I'm not in the path of the light?

 

[TEXTILE GUY]

It's maybe easier if I ask the question like this:
If I have a focused source of light that lights up some detail on a screen - how do I perceive that detail on the screen if I'm not in the path of the light?

View attachment 378224

Spose it depends .... If its additive colour, the scatter of the main source onto the screen will give you a visual perception of the image.

If its subtractive colour, then you would only see the reflectance of the screen.

 

[mister]

I'm having a brain-freeze here.

My initial question was how the light that reaches our eyes remains cohesive in a way that allows us to see the defined edges of an object. If I'm outdoors and light is coming from many directions and reflecting off an apple to reach my eye - it feels like I should get a hazy perception of the apple because it seems strange that wherever I stand, I'm in the right place to receive a cohesive 'bundle' of light representing the apple. Ugh.

Anyway.

It's maybe easier if I ask the question like this:
If I have a focused source of light that lights up some detail on a screen - how do I perceive that detail on the screen if I'm not in the path of the light?

With great software!

 

[saor]

Spose it depends .... If its additive colour, the scatter of the main source onto the screen will give you a visual perception of the image.

If its subtractive colour, then you would only see the reflectance of the screen.

Scatter surely can't account for my being able to see the image on the screen, can it? If I had 10 people in the room with me - each of them would see the image on the screen, but they can't all be privy to sufficient scatter-light to see the image?

 

[Solarion]

I'm having a brain-freeze here.

My initial question was how the light that reaches our eyes remains cohesive in a way that allows us to see the defined edges of an object. If I'm outdoors and light is coming from many directions and reflecting off an apple to reach my eye - it feels like I should get a hazy perception of the apple because it seems strange that wherever I stand, I'm in the right place to receive a cohesive 'bundle' of light representing the apple. Ugh.

Anyway.

It's maybe easier if I ask the question like this:
If I have a focused source of light that lights up some detail on a screen - how do I perceive that detail on the screen if I'm not in the path of the light?

View attachment 378224

You would likely just see a dot on the screen but not any details. All depends on what qualities of reflection the screen has. If it's black or white for eg.

 

[saor]

You would likely just see a dot on the screen but not any details. All depends on what qualities of reflection the screen has. If it's black or white for eg.

Just assume regular white light incident upon a white screen with some detail / picture printed on it. The diameter of the light-beam is sufficient to cover the picture on the screen.

 

[Bobbin]

Because light is both a wave and a particle? (JK, I don't know).

Interesting factoid though: As most of us know one can observe a laser light from the "side" even though it is supposed to be a uniform straight line of light. This is because of the scatter effect as it passes through the air and reflects off particles etc... Apparently you cannot see the same laser in a vacuum unless pointed directly at you.