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Question
What are the advantages and disadvantages of using a reflecting telescope?
Solution
Advantages:
- The main advantage is reflector telescope can escape from chromatic aberration because wavelength does not affect reflection.
- The primary mirror is very stable because it is located at the back of the telescope and can be supported in the back.
- More cost-effective than refractors of similar size.
- Easier to make a high-quality mirror than a lens because mirror needs to only concern with one side of the curvature.
Disadvantages:
- Optical misalignment can occur quite easily.
- Require frequent cleaning because the inside is exposed to the atmosphere.
- A secondary mirror can cause diffraction of original incoming light rays causing the “Christmas star effect” where a bright object has spikes.
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