Even though not all digital cameras offer automated focus-stacking of focus-bracketed exposures, the Panasonic and Olympus micro four thirds cameras have been doing it for several years so far. I wanted to compare it with computer focus stacking and, with my garden orchids blooming, I finally did the test.
One of the advantages of mirrorless cameras for macro photography is the absence of camera shake induced by mirror and shutter slap. The electronic shutter does wonders in static subjects in all cases.
Panasonic uses a 4K movie-like mode to do the in-camera focus stack using a large number of images but the resulting image is 4K-sized. The results are excellent though. My Olympus EM1-II uses up to 14 images but you get a 20 MP jpeg and also the focus-bracketed images. Both brands offer of course many more focus-bracketed pictures for you to stack later if you do not want to do it in camera.
I made my photos with the superb 12-100 f/4 zoom wide-open. Check the Olympus website to see which lenses are currently compatible with in camera focus-stacking.
Because I can make a comparison with the Olympus and Helicon Focus I am providing you here the images. The results in a nutshell are that for deep focus stacking both methods can produce artifacts but Helicon Focus allows you to edit the stack and remove them. If the subject does not require large focusing changes both are actually comparable.
Please let me know what do you think… you might see details that escape me!