Home-Built Scanning Tunneling Microscope (2015) • Hacker News Board

Re: Home-Built Scanning Tunneling Microscope (2015)

#81

Post by JabavuAdams » Fri, Apr 09, 2021, 4:27 AM UTC

feralimal wrote: post #32

gryn wrote: post #27

Earlier quoted context omitted.

do you think your eye is not a sensor ?

Of course your eye is a sensor. As are all your senses. The difference is that the input it receives is unmediated by external sensors and software. Visualising atoms or DNA is fine, but it is an inferior source of information. By a long way. Imagine you were born deaf and couldn't hear music. But that someone showed you a music visualiser. Do you think if you were watching the output of that visualiser you would now…

How is it inferior? We can't see in for e.g. the IR spectrum. But we can turn an IR image into a false-colour image that our eye and brain can make great use of. Using your eyes to directly see in IR will inherently be inferior to processing the results from a sensor into a form that we can see.

You seem really hung up on some pedantry about "see" and "seeing". Why? This may seem like some kind of strong criticism to you, but it just seems as though you are unaware of these technologies and haven't really thought through what constitutes a measurement or observation.

Re: Home-Built Scanning Tunneling Microscope (2015)

#82

Post by JabavuAdams » Fri, Apr 09, 2021, 4:30 AM UTC

feralimal wrote: post #25

Yes, look at all that squashed DNA, lol. Seriously though, how do we know that is DNA? It just looks like wiggly worms. And the DNA pic is black and white, but the picture of graphite is in colour. How is it in colour? Is it 'enhanced' with photoshop or something?

Molecular biologists aren't stupid. They fluorescent tagged the pieces that get incorporated into the DNA and not into anything else. There will have been positive and negative controls to gain confidence that the tagging worked as expected.

You might want to lose the snarky attitude as it's not a good look when you're really ignorant about the techniques you're sneering at. You seem curious. Just learn without the snark.

EDIT> This is the kind of thing you learn in 1st and 2nd year university biology courses. Especially cell bio / molecular bio lab technique courses.

Re: Home-Built Scanning Tunneling Microscope (2015)

#83

Post by fest » Fri, Apr 09, 2021, 5:44 AM UTC

hellbannedguy wrote: post #75

Reminds me of a Craigslist ad I saw a few years ago. U.C Berkeley bought a new electron scanning microscope, and offered the old one free to anyone who wanted it. The ad right there with the free couches, and nicknacks. I probably couldn’t afford to get it working, but I think about it often. Could you imagine having a scanning electron microscope in your bedroom?

This account details on what you'd go through if you got one https://mobile.twitter.com/nanographs

Re: Home-Built Scanning Tunneling Microscope (2015)

#84

Post by fest » Fri, Apr 09, 2021, 5:50 AM UTC

jacquesm wrote: post #15

I think I'm going to build this with my kids. What better way to show them atoms than to actually make them build a microscope that shows you the things directly?

There's also this recent DIY project: laser confocal microscope which also seems to be a fun build: http://www.gaudi.ch/GaudiLabs/?page_id=652

Laser confocal microscope seems to be a little more relatable/less abstract (um vs nanometer scale).

Re: Home-Built Scanning Tunneling Microscope (2015)

#85

Post by regularfry » Fri, Apr 09, 2021, 9:18 AM UTC

anitil wrote: post #58

ahartmetz wrote: post #50

I worked with a simple STM in a lab exercise. At the beginning, we created a new, clean tip. Guess how we did that?... We cut a piece of ordinary steel wire diagonally with an ordinary wire cutter. Somehow we did it right - the first one worked. It was all somewhat fiddly and sometimes the image was noisy. But we did get images of atoms.

This reminded me of a Thunderf00t video where he created tiny jets for ammonia. I expected it would be some expensive procedure, but he just heated up some glass, stretched it and cracked it. Not every one worked, but it was surprising how mundane some super precise tooling can be

If your process can be "make a tonne of low-precision instances then screen for accuracy" you can get surprisingly good results in general, as long as the accuracy of each instance is relatively uncorrelated. It's a really handy pattern to have in your back pocket.

Re: Home-Built Scanning Tunneling Microscope (2015)

#86

Post by argvargc » Fri, Apr 09, 2021, 2:20 PM UTC

jacquesm wrote: post #57

argvargc wrote: post #53

Earlier quoted context omitted.

The GP's "statement" contained three relevant sentences, two ending with question-marks. I learned from both your answer and its parent, furthering conversation, for me at least.

Read the rest of their comments and see if you still feel that way. As well as the novelty account made for the express purpose of further derailing the conversation.

Yes, agreed. Though I stand by my account of the original comment. (And as such, based on that they may need to go back to troll-school.)

Re: Home-Built Scanning Tunneling Microscope (2015)

#87

Post by grkvlt » Tue, Apr 13, 2021, 7:36 PM UTC

fit2rule wrote: post #18

This is an amazing project, in so many ways. My first thought is, the implant business has now got a problem. Soon enough, anyone and their pal will be able, finally, to validate their silicon at adequate scale.

finally? imaging a silicon chip has never been a problem and home-build STMs are not needed.