Relationship between Scope Length & Eye Relief

[Raygis LasVegas]

Is there a general relationship between a scope's length and the eye relief?

Since the G&P 4x35 scope is longer than the G&P 4x30 ( ACOG ), would the G&P 4x35 have a longer eye relief?

G&P 4x35

http://www.wgcshop.com/pcart/shopper...11D_cat_Scopes

G&P 4x30

http://www.wgcshop.com/pcart/shopper...X32_cat_Scopes

[Digital_Assasin]

Originally Posted by Wikipedia.org

The eye relief of a telescope, a microscope, or binoculars is the distance from the eyepiece the eye can be placed at which the exit pupil is approximately the same size as the eye's pupil. A poorly designed optical system may force the observer to press his or her eye close to the eyepiece in order to see an unvignetted image, or alternatively may have an exit pupil larger than the observer's pupil at a comfortable viewing position, resulting in wastage of light and a dimmer than optimum image.

No, in general the "length" of the scope usually does not have an effect on eye relief. It all depends on where the Ocular lense focuses the exit pupil.

BTW the 4x30 / 4x35 is not the length of the scope. (optical magnification X objective lens diameter)


From Bushnell.com



Coated Optics
Coatings on lens surfaces reduce light loss and glare due to reflection for a brighter, higher-contrast image with reduced eyestrain. Bushnell® riflescopes are coated with a microscopic film of magnesium fluoride. More coatings lead to better light transmission.

Types of Coating
Coated – A single layer on at least one lens surface.
Fully Coated – A single layer on all air-to-glass surfaces.
Multi-Coated – Multiple layers on at least one lens surface.
Fully Multi-Coated – Multiple layers on all air-to-glass surfaces.

Exit Pupil
The size of the column of light that leaves the eyepiece of a scope. The larger the exit pupil, the brighter the image. To determine the size, divide the objective lens diameter by the power (a 4x32 model has an exit pupil of 8mm).

Eye Relief
The distance a scope can be held away from the eye and still present the full field-of-view. Bushnell riflescopes provide an extra margin of comfort and recoil safety with extended eye relief and soft neoprene eyepiece guards.

Field-of-View (F.O.V.)
The side-to-side measurement of the circular viewing field or subject area. It is defined by the width in feet or meters of the area visible at 100 yards or meters. A wide field-of-view makes it easier to spot game and track moving targets. Generally, the higher the magnification, the narrower the field-of-view.

Magnification (Power)
Riflescopes are often referred to by two numbers separated by an "x". For example: 4x32. The first number is the power or magnification of the scope. With a "4x", the object being viewed appears to be four times closer than when seen with the unaided eye.

Objective Lens Size
The second number in the formula (4x32) is the diameter of the objective or front lens in millimeters. The larger the objective lens, the more light that enters the scope, and the brighter the image.

Ocular Lens
The lens closest to your eye.

Parallax
A condition that occurs when the image of the target is not focused precisely on the reticle plane. Parallax is visible as an apparent movement between the reticle and the target when the shooter moves their head or, in extreme cases, as an out-of-focus image. Bushnell center fire riflescopes under 11x are factory-set parallax-free at 100 yards; rim fire and shotgun scopes at 50 yards. Scopes of 11x or more have an adjustable objective to adjust for parallax.

Precision Adjustments
The windage and elevation adjustments affect accuracy. Windage is the horizontal (left-to-right) adjustment, usually the side turret of the scope. Elevation is the vertical (up-and-down) adjustment, usually the top turret of the scope. Bushnell scopes feature 1/4 M.O.A. (1/4" at 1 windage 00 yards) or finerand elevation adjustments with audible clicks for greater precision.

Resolution
Resolution, or definition, is the ability of a scope to distinguish fine detail and retain clarity.