Editing Spotting scope

{{Short description|Compact high-power telescope}}
{{More citations needed|date=November 2007}}
[[File:Yukon spotting scope.jpg|thumb|A 100mm spotting scope with a paraxial 30mm [[finderscope]]]]

A '''spotting scope''' is a compact lightweight portable [[telescope]] optimized for detailed observation of distant objects.<ref>[https://www.merriam-webster.com/dictionary/spotting%20scope spotting scope, noun, Merriam-Webster Dictionary, .merriam-webster.com]</ref> They are used as [[tripod]] mounted [[optical instrument|optical enhancement device]]s for various [[outdoor activities]] such as [[birdwatchers|birdwatching]], [[skygazing]] and other [[naturalist]] activities, for [[hunting]] and [[target shooting]] to verify a [[marksman]]'s shot placements, for tactical [[ranging]] and [[surveillance]], and for any other application that requires higher [[magnification]] than ordinary [[binoculars]] (typically 20× to 60×).

The [[optical telescope#Light-gathering power|light-gathering power]] and [[optical telescope#Angular resolution|resolution]] of a spotting scope is determined by the diameter of the [[objective lens]], typically between {{cvt|50|and|80|mm|in|1}}.  The larger the objective, the more massive and expensive the telescope.

The optical assembly has a small [[refracting telescope|refracting]] [[objective lens]], an internal [[erect image|image-erecting]] system, and an [[eyepiece]] that is usually removable. The image-erecting system may use [[relay lens]]es, [[Prism (optics)|prism]]s such as [[Porro prism|Porro]] or [[roof prism]]s, or a [[catadioptric system]] of the [[Schmidt-Cassegrain telescope|Schmidt]] or [[Maksutov telescope|Maksutov]] design.  Spotting scopes may have a ruggedized design, a mounting interface for attaching to a [[tripod]], and an [[ergonomics|ergonomically]] designed and located [[control knob]] for focus adjustment.  Some spotting scopes also have in-built [[reticle]]s for [[stadiametric rangefinding]].

Spotting scope eyepieces are usually interchangeable to adapt for different magnifications, or may have variable zoom to give a range of magnifications. Magnifications less than 20× are unusual, as are magnifications more than 60× since the latter can lead to poorer image brightness, a narrow [[field of view]] and too much image shaking, even on a tripod.  The eyepiece mount layout can be "straight-through" (the eyepiece is on the same axis as the scope body), or "angled" (the eyepiece is at an angle to the scope body—usually 45 degrees).

The high magnification of spotting scopes makes them prone to image disturbance from vibrations, so they are often stabilized with [[tripod]]s or (less commonly) [[monopod]]s, which provide a stationary and steady platform. [[Tripod head]]s can be used to control any required movements of the scope.

==Gallery==
<gallery widths="200" heights="160">
File:Bundesarchiv B 145 Bild-P014590, Rossitten, Vogelwarte.jpg|An [[ornithologist]] uses a spotting scope at [[Rossitten Bird Observatory]] in 1939. This spotting scope has no zoom eyepiece, but three interchangeable eyepieces with different magnifications
File:US Navy Seals fires M-91.JPEG|A spotter (right) uses a spotting scope to assist a marksman. Spotting scopes are used on target ranges to avoid walking to the target to verify the placement of hits
File:2018-01-06 IBU Biathlon World Cup Oberhof 2018 - Pursuit Men 70.jpg|[[Biathlon]] coaches use spotting scopes to verify and optimize competitors shot placement
File:Aufgebautes Spektiv.JPG|Spotting scope on its tripod
</gallery>

==See also==
* [[Aircraft periscope]]
* [[Milliradian]], an [[angular unit|angular measurement]] used in [[reticle]]d scopes intended for precision shooting
* [[Digiscoping]], long-range [[videography]] using a spotting scope with a [[digital video recorder]] mounted to the eyepiece
* [[List of telescope types]]
* [[Monocular]]

==References==
{{Reflist}}

==External links==
{{Commons category|Spotting scopes}}

<!--Please consult [[WP:EL]] before adding links here-->
* [http://www.birding.in/birding_optics_spotting_scopes.htm Birding Scopes]
* [http://askabiologist.asu.edu/sites/default/files/resources/articles/bird_songs/advanced_birders_guide_5.pdf Ask-a-Biologist - Advanced Birders Guide - Spotting Scopes]

[[Category:Binoculars]]
[[Category:Refracting telescopes]]