Focus stacking is a technique where you take as series of exposures in which the depth of the image is sliced by a series of Planes of Principle Focus (PPF) and the 'Zones of Focus' associated with each slice overlap so when the 'within limits'* portions are combined the result is an image where the depth of field is equal to the limits of the closest and the furthest zone.
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Subject to front element 86cm, extension 6.5cm Camera 5D ISO 200 ƒ16 @ 1/20 Lens 70-200mm ƒ2.8L
@200mm |
Min' DoF required 9cm (3. 5/8") Three Slices - Moving Camera to shift PPF |
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Slice 1. PPF on Anther - Stamen and Petals out of Zone of Focus |
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Slice 2. PPF on Stamen - Petals and Anther out of Zone of Focus |
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Slice 3. PPF on the hairs on Petals, Anthers and Stamen out of Zone of Focus |
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The 'in focus' zones of the three images are combined to give the final image
* refer notes on Circles of Confusion