944

submitted 2 days ago by fossilesque@mander.xyz to c/science_memes@mander.xyz

60 comments fedilink hide all child comments

you are viewing a single comment's thread
view the rest of the comments

[-] Triumph@fedia.io 76 points 2 days ago

The reason this happens is because the tiny gaps between the leaves act as lenses, like in a pinhole camera.

[-] Wolf314159@startrek.website 21 points 2 days ago* (last edited 1 day ago)

A pinhole camera has no lens. The effect here is like a pinhole camera, but a pinhole camera is nothing at all like a lens. Pinholes diffract light. Lens refract light.

EDIT: Of course you can't resolve an image through diffraction. That's not how pinholes cameras work. Diffraction negatively impacts image resolution, but it absolutely happens when light passes through them. But, although lens do use refraction to resolve an image, that same process also has unintended negative effects on image resolution (spherical aberration, chromatic aberration, etc.). I didn't bring up any of that because it was ultimately a distraction from the important part: narrow gaps diffract light, lens refract light, and pinhole cameras do not work like lens.

[-] Quibblekrust@thelemmy.club 10 points 2 days ago

Pinholes diffract light.

The diffraction effects from a pinhole camera are not what make them work. In fact, diffraction makes the photographs worse than they otherwise would be. The pinhole makes an effective aperture for photography because it's small size produces small circles of confusion on the film plane. Ideally, you would make the hole as small as possible, but beyond a certain (small) size, defraction becomes the dominant source of blurring. So the size of the pinhole should be chosen to yield the best balance between geometric blur and diffraction blur.

The diffraction is merely a limit to the smallness of the aperture, and not what creates the image.

[-] Wolf314159@startrek.website -4 points 2 days ago

The diffraction effects from a pinhole camera are not what make them work.

I didn't say this, you did. You're chasing your own tail.

[-] Buddahriffic@lemmy.world 3 points 1 day ago

If you didn't intend to imply that, it's on how you communicated, not how they interpreted it. The way you listed what each does implied you were saying that's how their images worked.

[-] Quibblekrust@thelemmy.club 2 points 1 day ago

You made a parallel sentence construction:

pinholes diffract light.
lenses refract light.

You directly contrasted them. Refraction is obviously key to how lenses work. So it seemed to me like you were saying that diffraction is key to how pinholes work. 🤷

[-] Dasus@lemmy.world 1 points 2 days ago

Yea, but you could achieve this by placing a circle of cardboard in the middle or a ring that you attach to your lens.

I don't remember the guy but YT shorts I've seen a guy testing all sorts of different shapes and filters in front of his lenses or even just in front of his sensor without a lens.

Can't recall who.

Anyhow

[-] Opisek@piefed.blahaj.zone 2 points 2 days ago

Our window blinds at school had tiny holes in them for the strings to go through and they had the exact same effect. You could see the eclipse projected once the tables.