Originally posted by LeGuillotine Could it be possible to use focus correction system to make DOF deeper, in macro shooting for example?
Focus stacking, or Z-stacking as it is known, should be relatively easy to automatize with AF macro or other lenses. Obviously it would be tripod only, mirror up and probably electronic shutter required, plus you'd maybe need a fraction of a second of wait time between each shot to let the vibration caused by the focusing motor and movement to die. Also, unless the processing pipeline is REALLY beefed up, I doubt you could combine the image stack in camera at least if it is composed of more than say three images. Or maybe you could but processing time might be excruciatingly long.
At my work, I have done quite a bit of this Z-stacking on a Zeiss StereoDiscoveryV12 stereomicroscope, it's Zeiss camera and PC-based software. A stack of 20-30 images takes from 30s to a minute or two depending on how fast a PC we are talking about. Vibrations and movement obviously are to be avoided at all costs which is why the system sits on a freaking steady and heavy stone table. But the end result is worth it
In microscopy magnifications the DOF is, well, microscopic (
), so it really is a game changer. You get images that are in focus throughout the specimen: insect, moss, mineral fragment, your pubic hair, whatever
Edit: forgot to mention that those Zeiss microscope cams are truly puny in the megapixel department, from 3 to 5 depending on model, if my memory serves. So a stack of even just 5-10 full resolution Pentax FF or even K-3 images would be a real acid test for any in-camera imaging processor, I'd imagine.