Peeling an onion.
Still trying to teach myself the focus-stacking technique for macro photos. All of these were shot with a Canon 40D, EF 180mm Macro 1:35L USM lens, with the EF 2x II extender, for an effective focal length of 360mm, at about 1.5 ft. distance.
What I'm finding is that the focal plane is so thin with these extreme macro images, that Photoshop has a hard time of properly aligning the images and creating the layer masks.
This one was 4 exposures. Not even close to enough.