Eyepieces

The specifications of a telescope are NOT the only specs that matter. The other half of the equation is the specifications of the eyepiece. Telescope eyepieces are made in different models and sizes to accommodate different observing methods and celestial objects. For example, understanding the focal length of your optical tube divided by the focal length of your eyepiece will result in magnification, which in return can tell you whether it is more suitable for deep space low surface brightness observation or planetary/terrestrial high surface brightness observation. For example, if you wanted to observe an object such as the Andromeda Galaxy with a large apparent diameter, an eyepiece with a long focal length and large apparent field of view would excel over an eyepiece with a shorter focal length and small apparent field of view because it would be able to accommodate the size of the object at low magnification and high FOV while not getting dimmer images as you would with short focal lengths. If you plan on observing planets, a short focal length eyepiece with a small FOV will result in high magnification to observe details on the surface (eg. Great Red Spot). You'll get a dimmer image, but since planets are already bright as it is, this won't be an issue. - Note: Almost all eyepieces come in 2" or 1.25" barrel size forms.