Certified Ophthalmic Medical Technologist (COMT) Practice Exam

What effect do shorter focal length lenses or wide-angle lenses have on magnification?

1. Increase

2. Reduce

3. No effect

4. Variable

The correct answer is: Reduce

Shorter focal length lenses or wide-angle lenses typically reduce magnification because they allow for a wider field of view while decreasing the apparent size of objects in that field. When using a lens with a shorter focal length, the resulting image produced tends to be smaller compared to that produced by lenses with longer focal lengths. This principle is particularly relevant in optics where the relationship between focal length and magnification is a fundamental concept. Wider lenses create a more extensive view, which, while useful for capturing more information at once, does not effectively render the objects significantly larger in comparison to their actual size. In contrast, lenses with longer focal lengths magnify the objects more since the light rays converge more closely before reaching the image plane, effectively enlarging the object's image. Thus, while shorter focal length or wide-angle lenses serve a vital purpose in capturing broad scenes or providing depth perspective, they inherently reduce the magnification of the viewed objects.