Because when shooting, you focus your vision on a pistol iron sights, so you need to see perfectly sharp on a distance less than 1m. Not sure if you can “cheat” with glasses to have better vision on that distance, if your vision is healthy

You must still be looking where you want to shoot otherwise you could point in any direction since "you're just looking at the iron sights". By that logic I could make any distance shot even if I couldn't see anything past 1m.

You look at the target, but without focusing your vision on it - it is locked to the iron sights. So the target, which is black bulls eye, is always blurry when shooting. Increasing depth of field as described in the article, would be beneficial. No idea if prescription glasses would help for someone with no vision issues.

Before you start shooting, you perform a few practice lifts of you arm. One way is to close your eyes, raise your arm and then see where you are aiming. Adjust the position of your back foot if you're off the bulls eye. Key is to keep your wrist locked in position.

Once you raise your arm for real, you don't really need to look at the target, your hand and hence pistol will be in the right spot.

All you need then is to fine-adjust the sight alignment, hence why you focus entirely on the front sight post.

Once you get good you just know how to stand and such, so you'll be mostly bang on right away.

For this reason, if you get glasses for shooting, you'll want them made so your best focus is at the front sight.

why allow runners to wear shoes? https://live-production.wcms.abc-cdn.net.au/363e2578a2107bd2...

A common practice between optometrists is to always _under_prescribe.

Can I ask why?

Not an optometrist myself, so please excuse if I'm using all the wrong words here. The way it's been explained to me: you want to leave some challenge for the eye to overcome, so the muscles that do the focussing stay in training. If you overadapt, those muscles have less to do and could atrophy slightly, leading to ever more loss of eyesight.

Sounds plausible, at least!

Can you provide evidence to this? Every new prescription I have gotten for glasses through my entire life has been too strong and required my eyes to basically degrade to be correct. Avoiding getting new prescriptions too often is pretty much the only reason my eyes are okay.

An optometrist cannot see through your eyes, so they use that lens comparing machine and ask you "which is better", and that leaves plenty of room for the patient to bias the results towards "different from normal is 'Better'", such that they vastly bias their new prescription upwards. Even if every optometrist is thinking about that and purposely downgrading the results of that flow, that could still provide room for the ratchet effect of eye prescriptions that many people with glasses have experienced.

> Can you provide evidence to this?

Wearing glasses for 40 years and talking to ophthalmologists and optometrists.

Also I don't know where you are getting your glasses from, but where I am it's been decades now that the measuring of eyesight (with a machine) is done before the lens fitting, which mainly focuses on astigmatism.

I actually asked my opthalmologist if he could make my vision better than 20/20. He said no, but maybe with contacts.

For baseball hitting, that would be a colossal advantage.

I got my glasses a year ago and just did a checkup. Apparently my current vision (with glasses) sits at 21/20. They did two tests using the rotating lens machine.

I might have better vision (with glasses) than a lot of people who wouldn't get glasses because their vision would be good enough.

I'm in Germany and my glasses are mainly used to correct my astigmatism.

or allow cyclists to use motors! these "mechanical irises" seem like doping to me...

Interestingly from the article: “it's worth noting that Oh Ye-jin, the South Korean competitor who took Gold in the 10 Meter Air Pistol event this year, eschews the irises.”

There's a great video that asks and answers a lot of these questions. For instance, I didn't know you can use replacement legs in professional athletics:

https://www.youtube.com/watch?v=pfIWxFIVP_Y

> given that optometrists tend to slightly overprescribe anyhow

I've been wearing glasses for myopia since I was ~10 years old and this is exactly opposite of my experience. Optometrists almost always prescribe the number slightly lower than they determine using tests.

When my number was constantly increasing, I remember ordering the next available increment just because the prescribed number was slightly annoying when looking at far away objects.

Now my number has been stable for a decade and I still sometimes get annoyed when using glasses at the prescribed power.