The aperture that gives the sharpest image is generally considered to be the smallest aperture, also known as the highest f-stop number.
This is because a smaller aperture means the lens opening is narrower, which results in a greater depth of field.
A greater depth of field means that more of the scene is in focus, from the foreground to the background.
However, it's important to note that there's a trade-off between sharpness and other factors like diffraction.
Diffraction is a phenomenon that occurs when light waves bend around the edges of an object, which can cause a slight blurring of the image at very small apertures.
Therefore, while the smallest aperture may theoretically provide the sharpest image, in practice, there's an optimal aperture range where the image is sharpest without being affected by diffraction.
This optimal range varies depending on the lens and the subject matter.
For most lenses, the optimal aperture range is typically between f/8 and f/11.
It's important to experiment with different apertures to find the best setting for your particular situation.
