- the ability to distinguish closely spaced points as separate points.
- Resolution Limit
- smallest separation of points which can be recognized as distinct.
- Resolving Power
- resolution achieved by a particular instrument under optimum viewing conditions.
The concepts of resolution and magnification are often confused. Any image can be magnified without limit, but most will become blurry if we do this. A crisp image, sometimes referred to as a sharp image, is what is wanted. This means
- the image must be properly focused and
- the image must have adequate resolution.
In this image below, bacteria from a yoghurt culture have been placed on the head of a pin (a). When this image is magnified, even a small amount (see b) of blurry detail is apparent. But when the machine is adjusted to achieve high resolution, individual bacteria are easily seen even at higher magnification (image c has been magnified 83 times more than image a).