Originally Posted by Pete
I'll put the matter to rest with this final word on the subject:
I appreciate the effort, but I always find it interesting when somebody essentially posts that they are going to get the last word on a subject matter and everybody else better just shut up.
I already moved to a dedicated thread for lens issues, but since people are posting here instead I will put my responses in the same thread they posted in, for now. I would be happy if people moved to the other thread, butt I won't keep moving things over there if people insist on responding here.
Is it your position that the lens requirements would be different if both eShift images passed through the lens at the same time instead of different times? That is what some people are claiming.
Originally Posted by Dave Harper
And the merging of the two sub-frames, where each goes through the lens at different points in time, happens in your eyes and brains, AFTER the lens, so what's your point?
While the fact you posted is true, it is an irrelevant fact to the question of what is required of the lens. I know you don't understand the science of light and glass very well, but the claim you are making that the resolution requirements would be different if the two sub-frames went through the glass at the same time is false. The eye integrates the light that the lens has sent to places it wasn't supposed to, but whether the registration of that stray light goes to the brain at exactly the same time or at 2 times that are so close that the brain registers them as the same time, does not matter. As I said in the other thread a year and a half ago:
Originally Posted by darinp2
I view this as like test questions in school where the teacher would put irrelevant information and part of the class would change their answer based on it. In this case the irrelevant information is whether the left and right side are shown at the same time or at different times when each is being shown at higher frequency than the viewing system can perceive.
If people don't want to consider human vision they can consider what a camera would capture when taking a picture with a long exposure and how much smearing of the E and the 3 are allowed before a picture taken in such a way would show them as one object instead of 2, then how that amount of smearing compares with how much the E can be smeared when shown by itself and still be recognized as an E.
The minimum strength of glasses an optometrist needs to give a person to see the E3 does not depend on whether the E and the 3 go though the glasses in the same millisecond or different milliseconds. I know you don't understand that. I'm not sure what it would take for you to understand that basic thing about glass, lenses and light. You still don't seem to get that the E can be a lot more obscured when by itself than when next to the 3 and still have the human be able to identify the E and have somehow come to the rather crazy (IMO) position that you need to know when the E and 3 went through the lens before you can figure out how much the E can be obscured before it isn't identifiable as an E to the viewer.
If an optometrist put just the E up so small that no human could read it, then zoomed it slowly until the patient identified it as an E, then repeated the same thing starting with a super small E3, the size of the E in the first part where the patient could identify it would be smaller than the size of the E in the E3 part of the test. And again, it wouldn't matter whether those things were put up so the whole set was going through the glasses at the same time, or if only part of the images was going through the glasses in each instant (but so fast a human wouldn't know how the display was actually creating the images).
You still haven't explained why the amount of obscuring of the E allowed before the E is not identifiable in the E3 case would make the E unidentifiable at the same size when the E is all by itself. I believe I already showed that if you put a gray boundary around the E (simulating the obscuring a lens does, which is something every lens in the world does, but just to different degrees) then the E is easy to identify by itself, but makes the E disappear (and become half of a blocky 8) when right next to the 3.
In the E3 example the smallest detail is the vertical black lines between the E and the 3. A "good enough" lens for that image has to retain enough of that detail for the user to see it. Yet detail that small may have never passed through any lens (the one in the projector, the ones in a pair of glasses, and the lenses in human vision). Despite the fact that the finest detail in the composite image never passes through any glass is irrelevant, those pieces of glass still need to retain that fine detail. To do otherwise is to not be good enough, even if they were plenty fine for the low detail E and low detail 3.
I can lead a horse to water, but I can't make them drink.