Focus stacking, what is it ?
Focus stacking is a method used to merge pictures with different focal planes to one single image with an extended Depth of Field (DOF). The two pictures below show the first and last picture in a set of 16 pictures of a ruler. The depth of field in this case is close to 1 mm. I used a macro rail to move the camera less than 1 mm between each photo.
I loaded the 16 photos into Helicon Focus 7 and merged them.
The result is a picture where the sharp areas of the single photos have been merged into a larger depth of field.
Focus stacking is useful when the depth of field is shallow, this is typically the case in macro photography. In microscope photography where the depth of focus literally can be less than a razors edge focus stacking is, in some cases, a necessity. Focus stacking can also be usefull in normal photography. Here is an example with two photos, one with the foreground in focus and the other with the background in focus, that are combined into one picture with a sharp foreground and a sharp background.
