Recent Posts

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Podcast Episodes / Re: Episode 705
« Last post by CarbShark on Today at 09:35:15 AM »
CarbShark's suggestion that there is something (undefined) about the geometry of the lenses and how they bend the light that would make motion detection easier (which sounds like speculation), I've still not heard or read anything that even distinguishes the two - other than that one is hexagonal and other tends to be square by default.

That’s not it. Each element of a compound eye is pointed at a slightly different direction. So each is collecting light from a unique segment of the visible field with overlap

If an object is moving it’s movement is going to be apparent in varying degrees by the different receptors.



You were claiming that each ommatidium of a compound eye acts as a pinpoint camera, each providing a complete image of an object, which is what your analogy of taking half a basketball, putting multiple pinholes in it and holding it up to screen and letting the light from the sun pass through it onto the screen.  You’d get multiple images of the sun on the screen.

But that’s not how the ommatidia of a compound eye work.  Each produces a pixel of an object which are stitched together to produce the image of an object, if the animal has conscious awareness (doubtful with bearers of compound eyes).

Well, I did a little research and modified my view. You should try that sometime.

And, no, each facet of a compound eye does not produce a pixel. Each produces a partial image




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TV & Movies / Re: Rate the last movie you just saw.
« Last post by werecow on Today at 09:14:24 AM »
Suspiria (2018): I'm a bit of a fan of the original. TBH, this is a totally different movie, other than the names of some of the characters and it being a horror movie set in a dance school run by a coven of witches. But it's gorgeously shot and it has an artsy feel to it. It's a slow burn, but there's some really harrowing scenes (such as a very long death scene in which a girl is "danced to death" and thrown around like a rag-doll as if someone was operating a voodoo doll). I also really enjoyed the soundtrack, and tbh the abundance of eye candy did not hurt. The ending felt a bit sudden, though. Still, I had been looking forward to it, and even though I had to watch it over a span of two evenings (because I started too late at night), I was not disappointed. 9/10
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Podcasts / Re: Opening Arguments #TTTBE
« Last post by xenu on Today at 08:46:27 AM »
Ya that's a good point. I'm not sure if you have to sue the doctor and the manufacturer together or if you have to sue the doctored and then the doctor would sue the manufacturer.
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Podcast Episodes / Re: Episode 705
« Last post by werecow on Today at 08:38:28 AM »
CarbShark's suggestion that there is something (undefined) about the geometry of the lenses and how they bend the light that would make motion detection easier (which sounds like speculation), I've still not heard or read anything that even distinguishes the two - other than that one is hexagonal and other tends to be square by default.

That’s not it. Each element of a compound eye is pointed at a slightly different direction. So each is collecting light from a unique segment of the visible field with overlap

If an object is moving it’s movement is going to be apparent in varying degrees by the different receptors.
OK, how is that different from the pixels in, say, this:



(on the left; images on the right are depth mappings they reconstruct from the left image)

Admittedly, there may be some distortion at the edges there (although it's a little hard to tell). Maybe that's what they were talking about on the show. And in this paper they talk about the lower resolution (though I don't see how an even lower resolution compound eye would help matters):

Quote
Due  to  the  large  field  of  view, fisheye cameras have shown better performance than pinhole cameras for multiple tasks including visual-inertial odometry [19] and localization [10]. Hence, we adopt a multi-fisheye-camera  stereo  setup  for  dense  mapping  with  a  self-driving vehicle.  However,  fisheye  cameras  have  a  drawback:  the central region of a fisheye image has relatively low resolution compared  to  a  pinhole  image  which  subtends  a  smaller angle  per  pixel.  This  lower  resolution  degrades  the  depth estimation of far-away objects in front of vehicles, and this degradation  is  made  more  severe  with  downsampling  of fisheye images for real-time processing


But that’s not how the ommatidia of a compound eye work.  Each produces a pixel of an object which are stitched together to produce the image of an object, if the animal has conscious awareness (doubtful with bearers of compound eyes).
I don't think something needs to be consciously aware in order for that to be a requirement for image processing. Cameras do the same thing with pixels.
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Podcast Episodes / Episode #706
« Last post by Steven Novella on Today at 07:43:26 AM »
News Items: Microbes on Mars, Memory Works Backwards, Elephants without Tusks, Dunning Kruger and GMOs, Room Temperature Superconductivity; Who’s That Noisy; Name That Logical Fallacy; Your Questions and E-mails: Climate Change Around the World, Dangers of AI; Science or Fiction
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General Discussion / Re: how to get ownership of a domain name?
« Last post by The Latinist on Today at 07:32:21 AM »
I use Namecheap.  $8.88/year for .com, and they’ve got good service.

Domains cost money. I’m not sure what exactly you’re expecting?
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I think you nailed it.
Ferriss is a prototypical grifter. His book, The 4 Hour Body was full of unfalsifiable claims and research that was overextrapolated as well as the fact that it was all pointless n=1 stuff that he tried to make seem exciting with his 'human guinea pig' thing.
Even when you look at the records he does actually hold, its just him finding technical loopholes for the titles, not the performance and so, while cute, are pointless.
So I would say there is nothing of value to be gained from Ferriss and probably anyone who would associate with him. Further more I do think there is a small harm in consuming his bullshit regularly because you can take it with all the salt you like, but some woo can still seep in and take hold at a gut level which you need to actively counteract with critical thinking.
The sad thing is that it just takes a long time for science to get from the lab to the plate and I think its best to focus on what we do know as opposed to what might be true unless we are on some cutting edge where such miniscule benefits can translate to cash.
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Tech Talk / Re: The DIY Repair Thread
« Last post by Desert Fox on Today at 06:15:00 AM »
I have a Black and Decker 18 v NiCad powered Drill / screw driver and a lawn trimmer.

Black and Decker appears to have dropped all support for them even though they were touted as universal. Black and decker instead went a 20 v Lithium Ion battery that is not compatible.

You can get aftermarket batteries but we seem to be in a situation where the company expects you to replace all your equipment. I have seen corded drills that are probably 40 or 50 years old and people still use them. I don't see why these NiCad tools cannot be around for decades but I am concerned with aftermarket support drying up.
On the upside, I got my perfectly servicable 18v drill for free.

I was given a free 14 V drill myself in addition to the 18 v ones I already have but none of the batteries I was given will hold a charge.  Ordered an aftermarket off of eBay. I ordered a new charger as well and it came with a 14 v that does hold a charge but best to have at least 2. 
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Forum Games / Re: Visual Counting
« Last post by ella on Today at 03:30:25 AM »
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Podcast Episodes / Re: Episode #703
« Last post by Beef Wellington on Today at 02:34:36 AM »
I'm really amused that after the CIA people literally told them "we are professional liars", they believed all the BS they got on the Osama story
including a silent helicopter. seriously, a silent helicopter.

You've got to believe to achieve-

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