Catadioptric telescopes such as Schmidt-Cassegrain or Maksutov-Cassegrain, use lenses and mirrors to gather and focus the visible light from the object. Catadioptric telescopes combine lenses and mirrors of specific shape to form an image. They allow fewer aberrations than refractor or reflector telescope which use only one or the other. By using both lenses and mirrors, the operator can focus in on more distant objects along with those that reflect less light. Professional stargazers as well as scientists prefer this type of telescope.
When both the salient features of the refractor and reflector telescopes are consolidated into one, you will most probably be left with a Catadioptric telescope. For the desired image to be magnified and viewed, both the mirrors and lenses direct and reflect the light towards a bigger mirror, thus, offering an overall better view. Although these sleek devices are small and easy to maneuver, they come with a heavy price. The Schmidt variety and the Maksutov are two very coveted variations of the Catadioptric telescopes. These scopes are the most versatile telescopes and have the best all around, all purpose design. The Schmidt-Cassegrain and Maksutov-Cassegrain telescopes are very light and portable. They have a large aperture in a very small tube. Away from city, with reasonably dark skies, an 8″ SC provides excellent views of the Moon, planets, comets, galaxies, nebulae and other faint deep-sky objects and can be used for astrophotography with good results. With a hefty tripod and mount, the larger models (10″ & 12″) can be a bit cumbersome for one person. There are more accessories available for these scopes than the other two. These telescopes are very popular with beginners as well as armature. Fully computerized “GO TO” telescopes with auto finding capability are also available, if you want to pay the price.
There are several advantages associated with this type of optical telescope:
- Most versatile type of telescope.
- Has a better near-focus capability than other types of telescopes.
- Excellent for deep sky observing or astrophotography with fast films or charged-coupled devices (CCDs) used in detecting images.
- Great for lunar, planetary, and binary star observing plus terrestrial viewing and photography.
- Closed tube design reduces the need for cleaning as the dust can’t penetrate as easily.
- Compact and durable.
There are several disadvantages associated with catadioptric telescopes:
- Much more expensive than reflectors or refractors.
- Not as appealing to the eye as its counterparts.
- Some slight light loss due to secondary mirror obstruction when compared to refractors.
Despite the disadvantages, the catadioptric telescope is by far the best one of the three main types to use. The multiple lenses and mirrors cut out aberrations and allow users to see more than they would with the refractor or reflector telescopes.