Diffraction Question
- Thread starter Paul-H
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- Ned
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It does still happen with macro lenses but you need to stop down a looooong way to get any depth of field so you accept the slight softening.
Not that anyone can ever tell as a frame filled with a subject viewed at any normal size won't really show diffraction - it's only for pixel peepers.
Not that anyone can ever tell as a frame filled with a subject viewed at any normal size won't really show diffraction - it's only for pixel peepers.
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- Terry
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Diffraction occurs when light is obstructed by an object in its path. in the case of a lens it is the blades of the aperture.
When the light waves strike they tend to bend towards the object, causing them to spread. It is this spreading that causes the softness.
With a Macro lens used for close up work, the magnification of the object is such that this softness is less obvious in terms of destroying detail.
never-the-less it is still present and is unavoidable in any system.
Some recent cameras have added an algorithm to their processing, that calculates this diffraction light spread and neutralises it with an equal and opposite effect. However this can not replace lost detail, it simply make the result look sharper.
When the light waves strike they tend to bend towards the object, causing them to spread. It is this spreading that causes the softness.
With a Macro lens used for close up work, the magnification of the object is such that this softness is less obvious in terms of destroying detail.
never-the-less it is still present and is unavoidable in any system.
Some recent cameras have added an algorithm to their processing, that calculates this diffraction light spread and neutralises it with an equal and opposite effect. However this can not replace lost detail, it simply make the result look sharper.