Rifle scope vs. open sights: A comparison of the structure and advantages

Foreword:

what does a rifle scope consist of, why do you need a reversing system and what advantages does a rifle scope have over classic open sights?

Reading time: about 4 minutes

Contents:

1. Basic structure

A riflescope consists primarily of a tube, also called a center tube, which usually has a diameter of 1 inch (25.4mm), 30mm, 34mm or 36mm, a reticle and usually up to 7 lenses.
These lenses are divided into three groups:

• Objective plane (2 lenses)
• Inversion system (2 lenses)
• Eyepiece level (up to 3 lenses)

Furthermore, it consists of a mechanical adjustment device with which the reticle can be aligned.
Optionally and depending on the version, there can be a zoom which is also mechanically adjustable and a diopter compensation.

With the tube, the 30mm variant is probably the most common, the larger the diameter, the fewer compromises the manufacturer has to make when accommodating the mechanics. In connection with this, a larger diameter of the central tube also allows larger adjustment ranges for the reticle and larger fields of view, but the relationships are extremely complex and not or only very rarely directly comparable.
Contrary to popular belief, diameter has no effect on brightness or light transmission.

This consists of another two lenses and as the name itself suggests, it ensures that our image, which is upside down through the lens, is reversed.

The eyepiece:
The eyepiece is the part of an optical system that is optically effective on the eye side. It consists of a single lens or a lens system on which the image captured by the eyepiece is imaged, creating a so-called "real intermediate image" which is virtually imaged for the human eye. So if we look through such a device, we do not see the object directly, but only the image on the eyepiece. If we have an optical device with a zoom, this is adjusted by moving the lenses in the eyepiece.

2. The reticle:

The reticle is the aiming aid, without it we would have nothing more than a telescope. They are available in all possible variants that are more or less useful, depending on the intended use of the rifle scope.
The reticle can be adjusted by adjusting the height or side of the rifle scope, so that you can adjust the line of sight and the bullet trajectory to each other. With older riflescopes, this meant that the reticle was often no longer in the middle after zeroing, but somewhere in the field of view. Today's so-called "centered" reticles circumvent this by tilting the reversing system when the reticle is adjusted, so that the entire field of view is shifted and the reticle always remains centered in the middle of the image.

Apart from the style of reticle, which is mainly a matter of personal preference, the first decision criteria are the choice between reticle on the 1st or 2nd focal plane and with or without illumination. In particular, I will go into the image levels in a post in the near future and then link it here, because that is very relevant when making a selection.

3. Why a scope and what are the benefits?

The main problem with open sights is focusing. Three things (rear sight, front sight and target) must be seen sharply and aligned with each other at the same time.
The rifle scope offers the possibility of showing the reticle and target sharply and on one level at the same time, which means that our eyes do not have to compensate for different distances to each other. This is a significant advantage even at short ranges where magnification is not required, and it also allows for a significant reduction in the time between target acquisition and a safe shot.

Sources:
Waidwissen.com
Wikipedia
Schott.com