The Difference Between an Angled and Straight Spotting Scopes
September 1, 2021
Many who begin considering the addition of a spotting scope to their optical toolkit are immediately faced with a choice. Should one choose a straight or angled eyepiece design and what do each of these two different shapes of spotting scopes as advantages? It’s an excellent question.
First, it should be noted that the optical performance of the two designs is, when both are of the same optical design (i.e., of the same product brand and product model family), entirely the same. The angle is simply a matter of the placement of the prisms of the optical system in different positions to achieve the straight or angled structure.
Straight Spotting Scope
The straight spotting scope design is the older of the two. Like the telescope and the binocular, many of the initial applications of the spotting scope were for military purposes. As such, it was to the advantage of the observer to be as low as possible to not be seen by the enemy. Thus, a straight design was optimal as it could be placed on a parapet or similar protective raised ridge and the observer’s eye positioned behind the eyepiece with minimal exposure of the rest of his (or her) body to possible harm. This concealment advantage is still why many hunters prefer the straight spotting scope design for their activities - it allows them to remain hidden while viewing their quarry.
Angled Spotting Scope
The angled eyepiece spotting scope has become quite popular recently among birdwatchers, as well as others using them for a variety of purposes. The angled eyepiece design allows for the use of a lower tripod position, or a smaller tripod entirely, as the spotting scope need not be placed directly in front of the observer’s eye but can be lower and the observer simply bending to view into it. This bending at either the waist of the neck is also less tiring during long observing periods as larger muscles are involved and no stretching up is needed should re-positioning of the spotting scope be needed.
Furthermore, if the angled eyepiece spotting scope is equipped with a rotatable tripod mounting collar, the spotting scope can be rolled along the established optical alignment (that is, while still remaining directed as the subject of interest to the observer) so that the position of the observer could be not only from above the spotting scope but perhaps from beside it or even from below it. This is a very popular feature for those afield with friends and particularly young children who are not sufficiently tall to look down into a spotting scope eyepiece but can easily look up into one. This rotational feature also makes angled spotting scopes the best choice when the optic is to be used from a vehicle while mounted on a window mount and therefore the observer needs to view into the eyepiece from the side of the spotting scope.
So when choosing a spotting scope, consider what type of observing you will be doing with it. Do you require concealment? Then the straight design is the best option. Do you plan to view for long periods of time and wish to do so comfortably? Do you plan to use it with other - particularly others of different heights? Do you plan to use it while it is mounted on a vehicle window mount? Then the angled style is the choice for you.