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Photos capture life inside a drop of seawater

smithsonianmag.com

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Re: Photos capture life inside a drop of seawater

#131

Post by ferdychristant »

jebarker wrote: post #4

> But copepods typically range from about 0.2 to 1.7 millimeters in length, just large enough to magnify using conventional lenses and equipment Does that mean conventional macro camera lenses or a microscope?

There's a few 5:1 dedicated macro lenses. Around 2:1 and above though, handholding becomes near impossible and you almost always need focus stacking due to the very shallow depth of field. Not to mention powerful lights.

So even this "conventional" option that you can readily buy is quite the niche.

For a 0.2mm subject, 5:1 is not enough. Luckily, one can use a microscope objective on a camera, like this:

https://c7.staticflickr.com/1/411/31944206126_fee397795a_b.j...

It doesn't have to be a bellow, they can also be a fixed tube, but the idea here is that the camera's sensor is at a specific distance to the back opening of the microscope objective. It would be the same distance where normally the eye piece of the microscope goes.

This way, you can do 10:1, 20:1, 50:1, 100:1. You'll have ever greater problems though the more you magnify (vibration, light, composition).

The device in the bottom is an automated focus rail, a WeMacro in this case. You set a start point and end point, and it takes all photos in between. It can move by as little as 1 micron and is quite cheap.

Re: Photos capture life inside a drop of seawater

#133

Post by quchen »

enw wrote: post #76
icambron wrote: post #67

Earlier quoted context omitted.

To elaborate this point a bit: the "lottery" concept requires you to believe there's like a queue of souls and they each get allocated to different bodies, and you're lucky you got a fancy one instead of a microscopic shrimp. A different -- and to me, more plausible -- way to look at it is that "you" are an emergent property of a specific complex organism. How you actually emerge is a fascinating and difficult discus…

What would be the “me” if I were to clone myself 1:1? Would there be two “me”s? Or a the same old “me”, a single consciousness but two bodies?

The philosophical zombie might be an interesting rabbit hole for you! https://en.m.wikipedia.org/wiki/Philosophical_zombie

Re: Photos capture life inside a drop of seawater

#135

Post by bmitc »

dang wrote: post #125
bmitc wrote: post #65

Beautiful and interesting stuff! I have never heard of copepods before, but have now and will have to do some more reading. > Walter once got a call from an Orthodox Jewish organization wanting to know if there were pieces of non-kosher creatures floating in the New York City tap water. The answer was yes. Not to pick on them, but I found this illuminating on how religions present such a myopic view of life and what…

Please don't take HN threads into religious flamewar. This post is about as congenial as religious flamebait gets, but it's still that. Admittedly the upvotes such a post gets are a bigger problem than the post itself, but there's not much we can do about those. (This post was upvoted to the top of the thread when I saw it. I've marked it off topic now.) https://news.ycombinator.com/newsguidelines.html

I think I'll disagree that this is off topic. What I quoted is a literal quote from the article. I wouldn't have mentioned it or caught it if it wasn't. From my perspective, the entire point of the article is the beauty and smallness of things that we are otherwise unaware of. The idea that books thousands of years old didn't anticipate, and thus don't accommodate, such is interesting. And I thought the discussion was good.

Re: Photos capture life inside a drop of seawater

#136

Post by jiggawatts »

freetime2 wrote: post #132

This article reminds me that I’ve been meaning to buy a microscope to play around with. Any suggestions for an affordable, beginner-friendly microscope setup?

My experience is USB digital microscopes are much better because you can look at the picture on a big screen. The eyepieces of most cheap microscopes are terrible in comparison.

With a screen you can show the kids what’s going on. It’s a shared experience.

Re: Photos capture life inside a drop of seawater

#137

Post by jiggawatts »

m3kw9 wrote: post #59

Just imagine, you could have been born as one of quadrillion of these guys, but instead you are a human, that’s more than lottery luck we all got, if you can read this.

Imagine being one a trillion cells in a human body, born into slavery serving an unknowable entity called the Mind that may as well be called God.

Re: Photos capture life inside a drop of seawater

#138

Post by dang »

bmitc wrote: post #135
dang wrote: post #125

Earlier quoted context omitted.

Please don't take HN threads into religious flamewar. This post is about as congenial as religious flamebait gets, but it's still that. Admittedly the upvotes such a post gets are a bigger problem than the post itself, but there's not much we can do about those. (This post was upvoted to the top of the thread when I saw it. I've marked it off topic now.) https://news.ycombinator.com/newsguidelines.html

I think I'll disagree that this is off topic. What I quoted is a literal quote from the article. I wouldn't have mentioned it or caught it if it wasn't. From my perspective, the entire point of the article is the beauty and smallness of things that we are otherwise unaware of. The idea that books thousands of years old didn't anticipate, and thus don't accommodate, such is interesting. And I thought the discussion wa…

"religions present such a myopic view of life and what it means to be alive on Earth" etc. is generic religious flamebait. We don't want that on HN, because it leads (in the general case) to horrible threads that are as nasty as they are predictable. I'm sure that's not your intent, but we have to go by the effects these things generally have.

You may be right about connections to the article (I haven't checked) but that is not as important as preserving the ecosystem in general, which is the motive behind moderating HN this way; not arbitrarily but based on many years of experience with how these things usually go.

Re: Photos capture life inside a drop of seawater

#139

Post by mncharity »

photochemsyn wrote: post #95

If you want to go down another order of magnitude or few, fluorescent microscopy of single-celled organisms is pretty interesting. This collection of images is stunning: https://www.canadiannaturephotographer.com/epifluorescencemi... These techniques also revealed the sheer scale of microbial life, as even the clearest ocean water from the most remote, nutrient-limited tropical seas will contain as many as 100,000 ce…

> the sheer scale of microbial life [...] ocean water

There's also the sheer predation of it. IIRC, for some coastal surface biome I've long forgotten, viral half-life was like an hour, and a third of bacteria were virally lysed each day. A cup of beach water is not just teaming with life, it's a war zone.

Re: Photos capture life inside a drop of seawater

#140

Post by dekhn »

JKCalhoun wrote: post #19

I wish there were a way to "productize" this, or automate it at least. I'm imagining some sort of aquarium-like tank you stock with ocean water that is able to maintain the microscopic life, allow them to flourish. Meanwhile, some sort of slow or periodic pump draws aquarium water into an attached, miniature "photography studio" where an appropriate camera+lens feeds a constant live stream to a display or to the web…

I believe they operate one of these in the microscope exhibit at SF Exploratorium. They're right on top of the bay (literally on a pier) and sample the water all the time, and IIRC, they put the samples into accessible high-end microscopes.
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