How Are Magnification & Resolution Alike?

A magnifying glass increases resolution by making a small spatial area appear larger.

Resolution and magnification are both terms describing the amount and type of detail visible in an image. As magnification is performed on an image, the resolution of that image will often, but not necessarily, increase.

Definitions

Magnification is the process by which the spatial area occupied by an image is made larger. This is often achieved by passing the light of an image through a lens that spreads it over a greater area. Resolution refers to the size of the smallest detail preserved in an image, with higher resolution implying a smaller minimum size for visible detail.

Relationship

Practical concerns place lower limits on the spatial area of details that can be observed in an image. The human eye, for example, cannot perceive details smaller than a certain spatial area determined by the spacing of the eye's photoreceptors. Therefore, magnification allows smaller details to be observed by making them appear to occupy a greater spatial area than they would otherwise, thereby increasing the resolution of the image.

Empty Magnification

If the smallest detail in an image is already visible, then magnification will lead to no increase in resolution. Such magnification is referred to as empty magnification. Zooming in on a digital image in which individual pixels are already visible is an example of empty magnification.

References

• Georgia State University HyperPhysics: Magnification
• Michigan Tech Computer Science: Magnification
• Nikon MicroscopyU: Resolution