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| 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. |
Explanation
This comic shows diagrams of a number of different types of telescope, some real and others made up by Randall. It includes both refracting and reflecting designs; see 1791: Telescopes: Refractor vs Reflector for the important differences between them.
| Type | Real? | Refractor/Reflector | Description |
|---|---|---|---|
| Prime Focus | Yes | Reflector | |
| Herschelian | Yes | Reflector | |
| Newtonian | Yes | Reflector | |
| Galilean | Yes | Refractor | |
| Keplerian | Yes | Refractor | |
| Gregorian | Yes | Reflector | |
Transcript
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