Difference Between Magnification and Resolution

Magnification vs Resolution

Resolution and magnification are two very important concepts discussed under optics. The theories of resolution and magnification play a major role in fields such as astronomy, astrophysics, navigation, biology and any other field that has applications of optics. In this article, we are going to discuss what resolution and magnification are, their definitions, how the resolution and the magnification can be adjusted or changed, the applications of resolution and magnification, the similarities between resolution and magnification, and finally the difference between resolution and magnification.


Magnification is a property discussed in optics. In more common words, magnification means how many times the original image is magnified by a certain object or a method. The simplest kind of magnification is the magnification glass. This is also known as the simple microscope.

There are two methods for calculating magnification and other optical properties. These are ray diagrams and matrix representation. Ray diagrams are a simple method used to calculate factors such as magnification, object distance, image distance, whether the image is real or imaginary, and other related phenomena. The matrix method is also capable of doing all these calculations.

The ray diagrams are suitable for a small number of optical components (1 to 3), and the matrix method is much easier when it comes to large and complex systems. The magnification of objects seen through telescopes and compound microscopes depends on the focal length of the objective element and the eyepiece lens. The objective element can either be a mirror or a lens.


The resolution is another very important topic discussed in optics. When the human eye or any imaging device sees an object, what it actually sees is the diffraction pattern created by the object. The iris of the human eye or the aperture of the device works as a sharp edge, to create diffraction. When two objects, which are close to each other, is seen through such a device the diffraction patterns of these two objects tend to overlap. If the diffraction patterns of these two objects are sufficiently separated, they are seen as two separate objects. If they are overlapped, they are seen as one object.

The resolution is the ability of an instrument to resolve these close objects. The resolution is defined as the minimum angular separation between two objects, to see them as separate objects. The resolution depends on the aperture of the instrument and the wavelength of the observed light.

The resolution is also a factor discussed in image processing. Images have specific resolution values which tells the amount of details it contains.

Magnification and Resolution

  • Magnification gives how many times the image has been magnified by the instrument. Resolution gives the ability to separate between two closely placed objects on an image.
  • The resolution is the quality or the sharpness of the image. This is why SLR cameras, which have large apertures, produce very sharp images whereas point and shoot cameras lack in sharpness.
  • For instruments such as telescopes and microscopes the resolution also determines the maximum magnification the instrument can obtain.