Luminosity just means that the object is reflecting or emitting enough energy
Luminosity in terms of energy is standard.
The point being made (if Lessans is correct) is that we are not receiving an image of the object as it travels to us
However, both your "reflecting" and your "emitting" entail traveling, and there is no traveling which is instantaneous. There is no traveling in which the leaving and the arriving occur without a time difference. There is no traveling in which there is no duration between the leaving and the arriving.
we are seeing the actual object in real time
We see it some time after the light (whether it is reflected or emitted light) left its source. This is the real time at which and in which we see it.
With what is there to disagree?
If he is right, this version of sight does not involve time. Here is an excerpt again. I can't do better than him in explaining it.
“I am not that positive, but this is what I was taught.”
Once again, certain facts have been confused, and all the reasoning except for light traveling at a high rate of speed is completely fallacious. Scientists made the assumption that since the eyes are a sense organ, it followed that light must reflect an electric image of everything it touches, which then travels through space and is received by the brain through the eyes. What they tried to make us believe is that if it takes 8 minutes for the light from the sun to reach us, it would take hundreds of years for the reflection of Columbus to reach Rigel, even with a powerful telescope. But why would they need a telescope?
They reasoned that since it takes longer for the sound from an airplane to reach us when 15,000 feet away than when 5000; and since it takes longer for light to reach us the farther it is away when starting its journey, light and sound must function alike in other respects, which is false, although it is true that the farther away we are from the source of sound, the fainter it becomes, as light becomes dimmer when its source is farther away. If the sound from a plane, even though we can’t see it on a clear day, tells us it is in the sky, why can’t we see the plane if an image is being reflected towards the eye on the waves of light? The answer is very simple. An image is not being reflected. We cannot see the plane simply because the distance reduced its size to where it was impossible to see it with the naked eye, but we could see it with a telescope. We can’t see bacteria with the naked eye, either, but we can through a microscope. The actual reason we are able to see the moon is because there is enough light present, and it is large enough to be seen. The explanation as to why the sun looks to be the size of the moon, although much larger, is because it is much much farther away, which is the reason it would look like a star to someone living on a planet at the distance of Rigel.
This proves conclusively that the distance between someone looking and the object seen has no relation to time because the images are not traveling toward the optic nerve on waves of light; therefore, it takes no time to see the moon, the sun, and the distant stars. To paraphrase this another way, if you could sit upon the star Rigel with a telescope powerful enough to see me writing this very moment, you would see me at the exact same time that a person sitting right next to me would, which brings us to another very interesting point. If I couldn’t see you standing right next to me because we were living in total darkness since the sun had not yet been turned on, but God was scheduled to flip the switch at 12 noon, we would be able to see the sun instantly — at that very moment — although we would not be able to see each other for 8 minutes afterwards. The sun at 12 noon would look exactly like a large star, the only difference being that in 8 minutes we would have light with which to see each other, but the stars are so far away that their light diminishes before it gets to us.
More details can be added, but you hold that "Light is essential for sight", and (I think) you agree that light travels. From that it follows inescapably that something cannot be seen without its reflected or emitted light having reached the person who sees, and that means that real time refers to the seeing and not the reflecting/emitting, because the reflecting/emitting does not occur at the same instant at the same place as the seeing occurs.
Please keep in mind that we would see the same exact thing whether in delayed or real time. We would see the object through the reflecting/emitting light. It would be exactly the same. I think everyone is trying to grasp how it would be possible to see the object without the time it takes to get to our eyes. But this account does not depend on time, as just mentioned. It doesn't matter how far away a celestial object is or how close an object is to us. What matters is that they both meet the requirements for sight, which is their brightness and size, not their distance. If the celestial object is too far away, there will be no light at our eyes that would allow us to see it. A telescope might be able to magnify the light to create a larger image of the real object, which would allow us to see it, however faint. The James Webb Space Telescope, for example, is able to see distant objects we cannot see from Earth. Whether it sees the past or the present is the million-dollar question.
A telescope primarily magnifies the light rather than the object itself. The telescope gathers light from the night sky and then uses its optics to focus and magnify that light into an image. This process allows astronomers to see faraway objects that are too dim to be seen with the naked eye. The magnification of the image is achieved through the use of lenses or mirrors, which are designed to concentrate the light and make distant objects appear closer and larger.
NASA+5
The fact that luminosity necessarily entails traveling means that it is necessarily the case that nothing about luminosity changes the fact that light cannot leave and arrive at the same time.
The fact that light is essential for sight - together with the fact that light travels - means it is necessarily the case that a thing cannot be seen before light which it reflects or emits arrives, just as a thing cannot be seen at the very same time that it reflects/emits light.
With what is there to disagree?
I hope I answered your question above. Light is present at our retina in this version of sight There is no gap where light should be. You have to think in terms of 180 degree about face in how this version works, which automatically puts the light at the retina if we can see the object. Bear in mind that distance is not a factor here. I could be right next to you and not see you because light from the Sun hasn't arrived, but I could see the Sun turned on, even though it is 93,000 miles away. That is because it would meet the requirements of brightness and size, not travel time. I know I'm repeating myself, but I don't know any other way to explain it.
