Which of the following is not a factor when determining magnification?

Magnification in optical systems, such as eyeglasses or other lenses, is influenced by various physical attributes of the lenses, but not all factors relate directly to magnification.

The center thickness of the lens, lens curvature, and base curve are critical in determining how light will be refracted through the lens, hence affecting the image size perceived by the observer. The center thickness can impact the optical power of the lens; thicker lenses may have different magnification properties compared to thinner ones. Lens curvature directly influences how the light is bent; steeper curves may lead to increased magnification because they can focus light more effectively. The base curve is fundamentally connected to the overall design of the lens and also plays a role in the effective lens power relative to the geometry of the frame and how it fits on the face.

In contrast, pantoscopic tilt, which refers to the angle at which the lenses are tilted relative to the wearer’s face, primarily influences comfort, alignment, and peripheral vision rather than magnification directly. While it may impact how the lens performs in practice regarding visibility and comfort, it does not inherently change the actual magnification factor of the lens itself. Thus, pantoscopic tilt is not a determining factor for magnification.