It is often thought that a telescope is essential for observing. Certainly, anything that enhances human vision is extremely useful to the astronomer. But a simple pair of binoculars is an excellent tool for exploring the night sky.
Besides being far cheaper than a telescope, they are less cumbersome and are easy to use, especially if sturdily mounted on a tripod.
The following table, taken from Harrington (1990), summarises the pros and cons of various binocular configurations.
|Size||Pros & Cons|
|7×35||Easily hand-held; excellent wide-field views of Milky Way and deep-sky objects. Smaller exit pupil restricts dark sky effectiveness.|
|7×50||Easily hand-held; light-gathering ability sufficient for hundreds of objects; best choice. Larger aperture may cause sky-glow problems in urban and suburban areas.|
|10×50||Good choice for urban and suburban users who want higher magnification. May require a tripod.|
|10×70||Excellent for clusters, nebulae and galaxies. Heavy; tripod usually needed.|
|11×80||Excellent for faint objects. Tripod needed; heavy.|
- Harrington, P. (1990) Touring the Universe Through Binoculars. Wiley Science Editions.
- How to choose binoculars and telescopes (oneminuteastronomer.com)