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Comment by m31415 | Hacker News Reader

Why is this surprising at all? Any transparent material having a refractive index larger than air can be made to work as a lens. Pinhole cameras are much more interesting than this -- there the phenomena isn't refraction. An even more interesting lens is the Frensel lens [1].

[1]: https://en.wikipedia.org/wiki/Fresnel_lens

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I, personally, have never considered shaping a piece of ice into a temporary camera lens. It's awesome, because someone's done it, and no one thought to previously. It's surprising that no one's done it, because in hindsight it's obvious. Why hasn't someone done this previously and posted on the Internet about it? Because human ingenuity is awesome.

CORRECTION: A piece of _iceberg_, which makes this all even _more_ awesome.

While not a lens shaped from ice there are people who have been working on lenses made from untraditional materials. For example here is a guy, Prof. Joshua Silver's, who has been working on eyeglasses for the developing world. From https://www.medicalnewstoday.com/articles/302550.php:

> Each lens is made of two flexible membranes that move either inward or outward depending on the amount of fluid - a silicone solution - they contain.

> The lenses are connected to a small syringe that sits on each arm of the glasses, and the wearer can adjust a dial on the syringe to pump fluid in or out of each lens. When fluid is pumped in, the power of the lens is increased - correcting hyperopia, or farsightedness - while pumping fluid out decreases lens power, correcting nearsightedness.

Additionally he gave a Ted talk on the subject https://www.ted.com/talks/josh_silver_demos_adjustable_liqui.... Pretty interesting stuff. Granted this is all circa 2009-2015. Not sure what the current status of the project is.

don't forget people making mirrors using spinning liquid: https://en.wikipedia.org/wiki/Liquid_mirror_telescope

My favourites are the liquid crystal lenses. Essentially they are micron scale Fresnel lenses controlled by electric field. No moving parts, very thin, ideal for something like a camera module.

I'm surprised that nobody managed to commercialise it in that niche yet.

Do you have a link for that? They have used holographic optical elements to make shorter SLR lenses, although I don't think the image quality was excellent, but if they went to the trouble it must have been fairly good.

doesn't really seem commercial grade yet: https://www.imaging-resource.com/news/2015/10/05/this-smartp...

I've been wanting to make a liquid lens VR headset to try to solve for vergence-accommodation conflict.

It is very cool.

While he's possibly the first to think of it in a photography context, I have heard of an ice lens being recommended in a survival context -- fashion a lens to start a fire with the sun.

I've had no idea if it is actually practical; I'm sure you'd need some very good dry & fluffy tinder. This photo experiment tilts it much further into the 'Plausible' zone.

Mythbusters tried this and got some smoke, but IIRC not actual flames. Seemed to be pretty possible though.

I can see that being possible. Cold, winter air is very dry. And frozen water doesn't tend to seep into things.

> It's awesome, because someone's done it, and no one thought to previously. It's surprising that no one's done it, because in hindsight it's obvious.

I’m incredulous.

What about a wristwatch made of meat? Opening a parachute underwater? Stacking seven iPhones as a doorstop?

If you make a wristwatch out of meat and post a howto video about it on HN, you will be front page within an hour.

If you make a parachute for divers that uses thermal currents to lift them up at the correct rate for avoiding the bends, then you’ll help them focus on underwater photography rather that dying, to their benefit.

If you build a doorstop out of iPhones, you might not get a front page, unless you do something more interesting.

You’re thinking along the right lines! Keep it up.

Darn, foiled again. My sarcastic examples of useless ideas turn out to be useful.

Any beginner tips for brainstorming lead into gold?

1) Succeed at it 2) Write a post for HN 3) Profit

No one said it was surprising. "I was amazed by the strange beauty of the images I made with the first ever 10 000 year old lens." In fact he worked on the project for six months before leaving for Iceland, so it was whatever the opposite of a surprise is.

It's not interesting that it's possible. It's interesting that someone actually did it.

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