xkcd #3182: Telescope Types

Title text:

I'm trying to buy a gravitational lens for my camera, but I can't tell if the manufacturers are listing comoving focal length or proper focal length.

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Source: https://xkcd.com/3182/

explainxkcd for #3182

I'm trying to buy a gravitational lens for my camera, but I can't tell if the manufacturers are listing comoving focal length or proper focal length.
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[–] 3 points 10 months ago* (2 children)

The Core was possibly the worst movie I've ever watched. Seeing that here gave me PTSD.

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  • [–] 4 points 10 months ago (1 child)

    Ehh, it's like most of the extinction-event movies of that time. It's dumb at points, but if everything was realistic, everything would be pretty damn boring. It's in my top 10 of that genre.

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