There are plenty of HDR apps available, indeed some cameras and smartphones have an HDR mode that takes a series of photos very quickly one after the other with the bracketed exposures, stacks them together and erases the areas that are too dark or too bright, to give an even exposure. Focus stacking brackets the focus and creates a composite. This is akin to creating genuine HDR (high dynamic range) photos where you expose for the dark, the mid-tones, and the highlights, stack the images together and create a composite that is neither under- nor over-exposed on any of those regions. Bracketing the point of focus from the closest to the farthest points on the object of your photographic desire. A top-notch lens with the possibility to shot with a slightly smaller aperture, provided there is sufficient light and without pushing the ISO to noisy high levels might get around the problem. With a 1:1 macro lens you are hoping to get the most detail possible but if the lens is within a few centimetres of the subject, then parts of the subject a few millimetres in front or behind your focus will not appear sharp. I wrote about this effect among the Moken people for Discovery Channel back in the day.Īnyway, when you’re shooting close-ups of flowers and insects and such DOF becomes a real issue. Children who spend a lot of time swimming underwater without goggles can grow accustomed to the light levels and find that their pupils narrow and they can see sharper detail. This is part of the reason why things look blurry under water – there’s less light and so the pupils of your eyes open wider meaning a shorter DOF for your vision. Conversely, f/22 is a smaller hole and lets in far less light so requires a longer shutter speed (see my starburst article for diffraction effects possible with such an f-stop).Ī larger aperture (smaller f-stop number, meaning a bigger fraction of the maximum size) means more light but a shorter DOF. So, f/2.8 is a big hole letting in lots of light (and needs to be balanced against a shorter shutter speed and/or lower ISO to get a properly exposed shot). f-stop is given as a fractional ratio to the lens’ focal length of the maximum size it can be opened. The f-stop is the size of the aperture, essentially the hole that lets light into your camera. In landscapes, the opposite is often required: foreground, middle ground and distance all needing to be nice and sharp (depending on your artistic wont, of course).įundamentally, DOF depends on the focal length of the lens, where you focus it and more importantly the f-stop you choose. Portraits often benefit from a nice sharp focus on the subject’s eye, but everything out of the plane of the face being out of focus so that backgrounds are blurred. (Then there are camera rails!)Ī narrow depth of field (DOF) has its pros and its cons in photography. There’s also a tool that lets you do the focusing on a bigger screen, like a tablet or computer, CamRanger, but you need a wireless tethering device. There’s also a tool for Canon dSLRs, DSLR Bracketeer, that lets you do the focus bracketing automatically and then you do the stacking in an app of your choice. There are several programs for focus stacking (Photoshop has it built in), Helicon Focus, Zerene Stacker, Picolay, and CombineZP (there are many others just search for focus stacking software). UPDATE: Been taking another look at this and applied focus stacking to my latest moth photo. UPDATE TO ANOTHER UPDATE: The Canon utility was hopeless, luckily I found a bit of open source software that takes back control much better and used it to focus stack yesterday morning’s moth and then combine the images, to much better effect.ĪNOTHER UPDATE: It seems that the Canon EOS Utility should allow me to automate the process focus bracketing with my 6D…just installing and will test with tomorrow’s moth…assuming there’s another stunning species to photograph…may give it a miss if it’s just another Clouded Drab.
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