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bentpins | 5 years ago

Maybe I'm missing something but how is the image so clear? CDs don't have a mirror like surface, they reflect light in unusual ways

discuss

simias|5 years ago

The rather shallow angle probably helps a lot. On top of that the camera probably has some form of auto white balance which will counteract the tint the CD will give to the image.

Here's a quick proof of concept using a random CD and my phone's camera: https://svkt.org/~simias/up/20200914-000627_psx-cd-reflectio...

Note that the color of the reflection is not much different from a normal picture (visible at the bottom). For added difficulty I used an original PlayStation disc, that's dyed black: https://svkt.org/~simias/up/20200914-000836_psx-cd.jpeg

jeffbee|5 years ago

It's very HN that we've been trolled into debating the irrefutable, widely-known, totally obvious fact that a CD reflects light.

gibolt|5 years ago

The quarter helping to hold down the CD may also contribute by blocking overhead inbound interference.

formerly_proven|5 years ago

Use a pressed CD (which are good mirrors at this angle), not a blank CD (which are tinted).

jeffbee|5 years ago

I just pointed a CD at my face and it's pretty much a mirror. What unusual reflection did you expect?

bentpins|5 years ago

Some rainbow diffraction I guess. It has been a long time since I've used a CD https://www.google.com/search?tbm=isch&q=cd

unknown|5 years ago

[deleted]

TaylorAlexander|5 years ago

Well I noticed it's a CD-RW which is a peculiar device, so maybe it doesn't reflect the same as normal CDs.

djmips|5 years ago

I think you probably haven't played around with CDs more than just to play them.

the_svd_doctor|5 years ago

I also don't really get it. Looks too clear and sharp for a CD reflection.