A long-focus lens is needed for this kind of shot, however.

Long-focus lenses are best known for making distant objects appear magnified.

Two orbits later, they went down themselves, taking cameras with long-focus lenses to record the star-patterns at the bottom of the shaft.

Long-focus lens: any lens with a focal length longer than the diagonal measure of the film or sensor.

The combination of these two groups produces a lens assembly that is physically shorter than a long-focus lens producing the same image size.

A true telephoto lens is designed to require less bellows extension than a long-focus lens of the same focal length.

A long-focus lens of small aperture can be of very simple construction to attain comparable image quality: a doublet (two elements) will often suffice.

But such simple lenses are not telephoto lenses, no matter how extreme the focal length - they are known as long-focus lenses.

He finally observes "long-focus lenses have usually a larger aperture than short ones, and on this account have less depth of focus" [his italic emphasis].

The angle of view and other effects of long-focus lenses are the same for telephoto lenses of the same specified focal length.

Besides being used in an astronomical role in astrophotography, telescopes are adapted as long-focus lenses in nature photography, surveillance, machine vision and long-focus microscopy.

The most common type of long-focus lens is the telephoto lens, a design that uses special optical configurations to make the lens shorter than its focal length.

A long-focus lens is one of three basic photographic lens types classified by relative focal length, the other two being a normal lens and a wide-angle lens.

Louis XIV of France ordered several long-focus lenses (86, 100, 136 feet respectively) for the astronomer Giovanni Domenico Cassini.

This is achieved by incorporating a special lens group known as a telephoto group that extends the light path to create a long-focus lens in a much shorter overall design.

The majority of cameras were handheld, and the filming crew used a variety of lenses, including long-focus lenses, fisheye lenses, and swing and tilt lenses.

In photography, a long-focus lens is a camera lens which has a focal length that is longer than the diagonal measure of the film or sensor that receives its image.

In photography and cinematography, a telephoto lens is a specific type of a long-focus lens in which the physical length of the lens is shorter than the focal length.

He suspects a neighbor of murder and watches him first with his eyes, then with binoculars, then through a long-focus lens, never snapping a picture but wondering if it is ethical to keep looking.

The Chief Engineer was not sure that he liked the idea of having his every move watched by long-focus lenses up in the hills--not that there was anything he could do about it.

Lenses of shorter focal length are called wide-angle lenses, while longer-focal-length lenses are referred to as long-focus lenses (with the most common of that type being the telephoto lenses).

I lament that there are no more powerful long-focus lenses in the Bronica range, for this means that I must carry my back-up Nikon, with fixed 500mm and 1,000mm for all really long shots.

Some photographic zoom lenses are long-focus lenses, with focal lengths longer than a normal lens, some are wide-angle lenses (wider than normal), and others cover a range from wide-angle to long-focus.

Two images taken from the same location, one with a wide angle lens and the other with a long-focus lens, will show identical perspective, in that near and far objects appear the same relative size to each other.

Maybe you were tempted to take handheld shots on telephoto - perhaps with a very good reason, lions in a zoo are not very approachable and often the only way to shoot them in close-up is with a long-focus lens.