sci.med.vision Google Group

Presbyopia: Its Cause and Cure

misa...@googlemail.com (Lelouch Lamperouge) — Sun, 08 Nov 2009 11:15:11 UT

[...]
Presbyopia: Its Cause and Cure
By W. H. Bates, M.D.
Presbyopia is the name given to the loss of power to use the eyes at
the near point, without the aid of glasses, which usually occurs after
the age of forty.
The text-books teach that this change is a normal one: but it is a
noteworthy fact that many other eye troubles often date from the time

Re: Methods That Have Succeeded in Presbyopia

mikabra...@gmail.com (Ms.Brainy) — Sun, 08 Nov 2009 01:57:40 UT

Any useful advice of overcoming gravity?

Re: contrast sensitivity, visual acuity, and Photoshop

mty...@mindspring.com (Mike Tyner) — Sun, 08 Nov 2009 01:09:24 UT

"Liz" <fraternobom...@yahoo.com> wrote
BinGO gurlie.
That's the principle, absolutely.
Generally a "cycle" would be a repetition, any repetition.
But if we limit our analysis to "cycles" we can plot as waves, then the math
becomes MUCH simpler, because we already have mathematics for waves. The
same trigonometry works for all waves, in electricity, water, and music, as

Re: contrast sensitivity, visual acuity, and Photoshop

salmon...@sbcglobal.net (Salmon Egg) — Sat, 07 Nov 2009 21:55:29 UT

In article
<da6362e5-b77e-40f4-87eb-101ce 2d9d...@c3g2000yqd.googlegroup s.com>,
Do you understand audio or temporal frequency? If you do, you understand
that your hearing system has limited high frequency response. That
response limits the sharpness of clicks you might be able to hear.
Similarly, your visual system has limited capability for things changing

Re: Color Correcting Lens Coatings?

jganda...@gmail.com (Joe) — Sat, 07 Nov 2009 20:01:29 UT

On Fri, 06 Nov 2009 21:22:51 -0800, Salmon Egg
OK, I am not *completely* color-blind to red - as I mentioned before,
I do see red, just not very well. If the ambient light is brighter, I
see red better, but if the ambient light is dim, red doesn't show up,
so I am left with the impression that the color is black (no color).

Re: contrast sensitivity, visual acuity, and Photoshop

fraternobom...@yahoo.com (Liz) — Sat, 07 Nov 2009 19:28:25 UT

Mike, your explanation is SO much better than those articles!
Degrees as in 0 to 360? The way astronomers say something is "15
degrees above the horizon"? I think so. In other words, straight
ahead is 0, straight overhead is 90, and the space in between is
divided into 90 equal pieces...
Yes, I see how the distance wouldn't matter.

Re: contrast sensitivity, visual acuity, and Photoshop

fraternobom...@yahoo.com (Liz) — Sat, 07 Nov 2009 18:29:25 UT

I'm not complaining about the measurement aspect. Of course you have
to use math to measure it.
I'm saying that I can't figure out WHAT is being measured. I mean in
terms of anything concrete that I know what it is.
Unfortunately I don't know what "spatial frequency", "transfer
modulation function", are. Sorry! Yes, I looked them up and read

Re: contrast sensitivity, visual acuity, and Photoshop

mty...@mindspring.com (Mike Tyner) — Sat, 07 Nov 2009 15:46:26 UT

"Liz" <fraternobom...@yahoo.com> wrote
Pretend your eye is the center of a circle. If you look at a letter "E"
several feet away, you could measure the height of the letter in degrees,
couldn't you?
The nice thing about degrees is we don't care how far away something is, as
long as it covers the same angle.

Re: contrast sensitivity, visual acuity, and Photoshop

red...@ev1.net.invalid (Robert Redelmeier) — Sat, 07 Nov 2009 14:53:18 UT

Liz <fraternobom...@yahoo.com> wrote in part:
Some of us like that stuff !
People often use terms imprecisely. I would say "visual
acuity" presumes some sort of standard contrast, while
"contrast sensitivity" is somewhat more general.
Oh, a photog -- look up "Modular Transfer Function" ...
maybe not if you dislike abstraction more than ignorance.

Re: contrast sensitivity, visual acuity, and Photoshop

salmon...@sbcglobal.net (Salmon Egg) — Sat, 07 Nov 2009 12:44:21 UT

In article
<00b8ae25-844f-4164-9c2b-e8aa6 f5e8...@p35g2000yqh.googlegrou ps.com>,
Sorry Liz. If you are trying to quantify these terms to an objective
standard, I do not see how you can avoid math. Otherwise, all you have
is English teach arty-fartiness. Just take the Snellen chart. Not all
letters require the same acuity to be read. The cycles per degree or

Re: Color Correcting Lens Coatings?

salmon...@sbcglobal.net (Salmon Egg) — Sat, 07 Nov 2009 12:28:42 UT

In article
<b9a6d9ca-9114-4ed5-ae0a-6c23c 79c8...@k4g2000yqb.googlegroup s.com>,
In this quote note that "color balance" is not defined.
"Treatment" is not the right word to use."Modified" or "compensated"
might be a better word to use. As treatment, the method is equivalent to
treating myopia with glasses. Yjr best you can say is that myopia is

Re: Lies I have believed about Presbyopia

mty...@mindspring.com (Mike Tyner) — Sat, 07 Nov 2009 12:27:48 UT

"Lelouch Lamperouge" <misa...@googlemail.com> wrote
Nothing original, nothing that works.

Methods That Have Succeeded in Presbyopia

misa...@googlemail.com (Lelouch Lamperouge) — Sat, 07 Nov 2009 12:15:42 UT

[...]
Methods That Have Succeeded in Presbyopia
The cure of presbyopia, as of any other error of refraction, is rest,
and many presbyopic patients are able to obtain this rest simply by
closing the eyes. They are kept closed until the patient feels
relieved, which may be in a few minutes, half an hour, or longer. Then

adult website accounts

dada_do...@yahoo.com (dada) — Sat, 07 Nov 2009 07:41:55 UT

the following adult websites are available at massively reduced prices
(all are "acquired" by me personally lol ;-) )
[link] - [link] - [link]
- [link] - [link] - [link]
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Re: Color Correcting Lens Coatings?

fraternobom...@yahoo.com (Liz) — Sat, 07 Nov 2009 06:36:48 UT

Fascinating!!! I think this is what birds do (bear with me). They
have drops of colored oil in each cone, which sharply cuts off the
spectrum it can pick up on one side of its curve. This is supposed to
allow the bird to distinguish more colors, or different colors more
easily. It must only work if the brain somehow sorts the input from