Blurry vision underwater is due to pupil dilation, which can be controlled to see as if wearing mask

[lowviz]

Would you mind taking your babble off of this thread?

 

[tursiops]

@DavBuc is conflating squinting (eyeball squeezing to change the shape of the eyeball so as to bring things into focus) with pinhole viewing (simply getting a smaller aperture for more depth of field).

 

[DavBuc]

@DavBuc is conflating squinting (eyeball squeezing to change the shape of the eyeball so as to bring things into focus) with pinhole viewing (simply getting a smaller aperture for more depth of field).

No, I'm not but thanks for the feedback.

Here's a really simplified explanation that I found on a quick search, it may "clear things up for you", pun obviously intended.

What’s Up With That: How Squinting Helps You See Better

 

[CT-Rich]

I need more coffee

Yes, you should lay off the coffee, possibly reduce the amount of cocaine you are adding to it.

Squinting might help a bit, a pin hole will work much more... as for look silly in a restaurant, try dressing better (avoid loud colors and make sure your fly is zipped)....

Another solution is more light. A massive lamp will make the aperture in your pupil much smaller. In bright sunlight, on a sandy white beach, I can read without glasses (well at least with my out of date prescription).

 

[tursiops]

No, I'm not but thanks for the feedback.

Here's a really simplified explanation that I found on a quick search, it may "clear things up for you", pun obviously intended.

What’s Up With That: How Squinting Helps You See Better

Yep, there is surely an effect of "one-dimensional" pinhole'ing from squinting, but the larger effect has to be eyeball shape. One reason for my assertion is that (as far as I know) the squinting/pinching thing only works for myopics, because the eyeball distorts to be somewhat shorter, front to back, to get the retina into the focal plane.

 

[DavBuc]

Yes, you should lay off the coffee, possibly reduce the amount of cocaine you are adding to it.

I resent the inference that I am partaking in illegal drug use. You are also engaging in the "Ad hominem" attack whereby you attack the person and their credentials rather than the opposing side of the argument.

Squinting might help a bit, a pin hole will work much more... as for look silly in a restaurant, try dressing better (avoid loud colors and make sure your fly is zipped)....

I don't know.. if I look over at a nearby table and see some dude pushing on his eyes with his fingers trying to read, I'm thinking that guy looks freaking ridiculous and I'd point it out to my dinner companions who would all have a good laugh, as opposed to me pointing out a guy with his fly open, I don't think I'd bother trying for a laugh because it just isn't that funny.

Another solution is more light. A massive lamp will make the aperture in your pupil much smaller. In bright sunlight, on a sandy white beach, I can read without glasses (well at least with my out of date prescription).

You might be able to read in the sun without glasses but the UV damage to your eyes isn't worth it. Wear quality sunglasses.

 

[DavBuc]

Yep, there is surely an effect of "one-dimensional" pinhole'ing from squinting, but the larger effect has to be eyeball shape. One reason for my assertion is that (as far as I know) the squinting/pinching thing only works for myopics, because the eyeball distorts to be somewhat shorter, front to back, to get the retina into the focal plane.

@tursiops forget about checking reliable internet sources that support my point. Try this- gently press on your eyeball and notice how the eye is rather firm. It takes a LOT of pressure to distort it even a little bit. Now, try squinting enough that your field of vision is mostly eliminated to a slit. Feel how much pressure you are actually putting on your eyeball with your relatively flaccid eyelids. Do you really think it's making a difference? Sure if you squeeze even more, REALLY hard you "might" get some distortion of the eyeball but you're way past the point where you're even looking through an aperture that has already provided a reduction of blur similar to a mechanical slit such as a pinhole or making a small circle with your fingers as others have suggested.

 

[tursiops]

@tursiops forget about checking reliable internet sources that support my point. Try this- gently press on your eyeball and notice how the eye is rather firm. It takes a LOT of pressure to distort it even a little bit. Now, try squinting enough that your field of vision is mostly eliminated to a slit. Feel how much pressure you are actually putting on your eyeball with your relatively flaccid eyelids. Do you really think it's making a difference? Sure if you squeeze even more, REALLY hard you "might" get some distortion of the eyeball but you're way past the point where you're even looking through an aperture that has already provided a reduction of blur similar to a mechanical slit such as a pinhole or making a small circle with your fingers as others have suggested.

Are you myopic?

 

[DavBuc]

Are you myopic?

Myopia with astigmatism with the rule in the od, with hyperopia and against the rule astigmatism in the os.

Because of the induced "natural monovision" I only need glasses for distance visually demanding tasks such as night driving and Sunday Night Football.

 

[CT-Rich]

Hmmm..... possibly squeezed the old eyeball one too many times?

This is a fun, silly topic... take a chill pill Phil... it will even out the coke and caffeine.

The first 3.8 million of our evolution we lacked UV absorbing glasses and corrective lenses. I think I wil avoid bursting into flames if left in direct sunlight. Knew goth chic that happened to..... that and crosses.... really didn’t do well with religious iconography. Awesome hickies, though...