Re: Accommodation in Aphakial Eyes -- Bates has not been disproven on this.

On Sep 1, 12:47 am, Zetsu <absolutelyinvinci...@xxxxxxxxxxx> wrote:
Hello,

What does he mean with the word, 'appreciably'? Most likely he is
implying that the change in the pupil was not so perceptible or
noticeable to the naked eye.

No. He means "not much" or "it is noticable but not large"

I try to give the guy the benefit of the doubt.

But.........

I really dont know how he came to that conclusion. A striking thing
about the normal eye is how much the pupil is constantly adjusting for
different light and interest levels. Surely?

It is a strange thing to say in my experience at first sight anyway.

However...............

I think it is true that the amount of sun energy entering a healthy
human eye where the retina is properly immersed in a wet "none dark"
gel like material and is not detached and vulnerable to heat damage,
is so tiny that as studies in the UK show it is not so damaging for
most as is popularly believed. But in places like india where sun
gazing has become a way of life? there *is* more evidence of
damage. Bates was a new yorker at 45? latitude. India is
equatorial.

Also since the eye is not corrected for different wavelength focus a
none true refracting eye could easily get more focused IR or UV energy
per cell than a normal sighted eye I would guess.

But clearly it is possible to look at the sun for a second with no big
deal and then enter a room and read a newspaper with no dramatic
effects.

And importantly the retina has the ability to adjust its light
sensitivity in daylight many orders of magnitude greater than whatever
the pupils effects are on regulating the amount of light reaching the
retina. (different to night time adjustment which takes longer) .

That could be what Bates was meaning if he compared pupil size to
actual real light meter levels rather than what might be perceived by
a human eye as being the light change level. But would he have that
kind of equipment back then?

So i am not exactly sure if he was on drugs or if he was operating at
a higher level of awareness!

Andrew

.

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