Long Draft Telescope (T50) on 7th Floor



You’ve probably seen telescopes like these in movies like Pirates of the Caribbean or other films from seafaring eras. These long-draw telescopes in their simplest forms are a pair of lenses, one near the front, and the other near your eye. The designer of the telescope can choose how much magnification it gives by deciding which lenses to pair together, as the ratio of how much optical power they have compared to each other will decide this. The designer also has to make sure it works with the final lens in the system: your eye! The muscles in your eye that adjust whether things are in focus far away or near are relaxed when you’re looking at distant objects, so it’s most comfortable for you to use a device like a telescope if your eye’s muscles are relaxed. The telescope is designed such that the light entering your eye behaves as though it is coming from far away, making for comfortable long-term use. This is also how modern binoculars are designed to work. Several of the telescopes in this collection here are some of the oldest pieces here in the museum, which you can tell from the animal skin housings used on these pieces.