"Tim Lamb" wrote in message
...
In message , The Natural Philosopher
writes
On 13/02/2020 22:52, bert wrote:
In article , "Dave Plowman (News)"
writes
In article ,
bert wrote:
In article , "Dave Plowman (News)"
writes
In article ,
Fredxx wrote:
I'm with Tim here. A lot of deterioration of sight is through lack
of
use of the accommodation muscles. While the lens does harden my
sight
deteriorate most when sedentary and focussed onto a screen with a
blank wall behind. Since then I choose to sit where if I look over
a
monitor I have a distant view.

Err, someone with perfect vision will only choose to have reading
specs
when it becomes impossible to focus close enough without.

Err if you can't focus close enough you haven't got perfect vision.

Err, no older person ever has, bert. But may well have had when
younger.

The worst killer for accommodation is varifocal lenses. The eye
muscles become very lazy.

Why would you get varifocals if you still could accommodate OK?

Oh dear.

You don't understand much about your own eyes, do you?

Well I've lived with them a long time so I Know them pretty well.

Apparently not.

:-)

From a point of technical ignorance, I'm with Bert.
Sat at the desk, I am wearing corrective reading glasses. Glancing through
the window, I can see trees on the horizon 1/2 mile away and all the bits
in between. However, nothing is in sharp focus. The registration on a van
parked 20m away is blurred but just about legible. If I take my glasses
off, the computer screen is blurred but everything else snaps into sharp
focus.

It remains my belief that adopting the bi-focals that Specsavers sold me
20 years ago would have caused endless dust/drizzle/
condensation nuisance during work related activities

I get very little of that and I wear glasses all the
time except when reading printed material or
doing very fine work, I'm short sighted.

The only time I get condensation is when
opening the dishwasher just as its ended
the final dry cycle. I just have to remember
to not have my head immediately over it
when I open the door and even when
I forget, it clears a moment later when
I move my head away.

and might also have led to a deterioration in distance vision.

Not sure if anyone has tested that. Bit hard to do.