Lens corrections. Let's just find the right subject. Which sounds for what do I need to know about lens corrections? Probably not much, but there's a couple of a couple of unique Capture One features that are well worth knowing. So pretty much if you ignore the lens corrections tool and never touch it, you can be safe in the knowledge that Capture One is doing the lens corrections for you in the background, as we see fit. So you'll see, as you load up an image in Capture One in the lens correction tool, If the lens is part of the lens data base, then it will show up automatically here. So I haven't done anything manually here, the fact that this image is in Capture One the meta data shows, it's using the Canon 24mm, so it pops up automatically in the lens correction tool. If you do nothing from then on, you're still getting some corrections. Now depending on the image, so lets shift to a different image as such, so we've got a different image here, shot with a phase one 110mm, so you s...
ee that automatically changes like so. By default, we always correct for chromatic aberration, and you'll see we have three sliders for distortion, this says sharpness fall off, just you can't see it on the interface as such, but sharpness fall of, so that's when the image softens to the edges, and light fall off. If after profiling the lens we don't feel that the distortion, sharpness fall of and light fall off is too great, then we leave it at zero. If it's a massively distorted lens that looks horrific at zero, then you'll probably see it has a value of 100 per cent, just to do that correction. But you'll see for this lens, there's not a huge amount of distortion going on, that's why it's left at zero. So you can pretty much leave all of this on default and be happy with the results, as such. A little note about chromatic aberration, it would probably be impossible to see anything on the screen in transmission here, but chromatic aberration will be corrected by default, but based again on the lens profile. But, no two lenses are the same, when they come off the factory production line they have a variation, which depending on the manufacturer could be quite broad or it could be quite small. But they're always a little bit different, each lens. So you might find that chromatic aberration correction isn't always 100 per cent reliable. What you can do it, say analyze, and then Capture One will look at the image, and it will do a custom chromatic aberration analysis for your specific camera and lens combination, which will give you a much better correction. These days, lenses are getting so good and so much better that the level of chromatic aberration is, kind of, shrinking a bit, so generally it's so negligible you can't even see it, unless you're doing some sort of, super pixel peeping at 400 per cent, or whatever. But it's good to know it's there. And it's a good step you can do at, perhaps, the end of your image processing, in that you can select a batch of images like so, and we can say analyze, and Capture One will do a batch chromatic aberration analysis like so. And it's really fast, so you may as well do it. For those images where you maybe have a little bit of chromatic aberration, then that will do a good job of taking it away. Now the unique thing about Capture One, is this option here, diffraction correction. So, lets bring up the viewer labels. So we've got two identical images here, let's zoom in to, probably, let's go for 50 per cent, and find, nah, lets do 100, let's find some detail somewhere okay, so, image on the left we shot at F5.6, so pretty open, image on the right was shot at F22. They both have exactly the same adjustments on them, I think, let me reset, okay, so I've reset so they're both at default. See, the image on the left at F5. looks sharper that it does at F22, and this will happen on any camera, that the tighter you put the aperture down, so when you shrink the aperture down, you get aperture caused diffraction, which causes a softening of the image. So, you might think I need loads of depth of field so I'm gonna shoot everything at F32, and my pictures will be nice and sharp front to back. That's not the case, because you're gonna get diffraction, which will soften the entire image. Fortunately, it's kind of a mathematical, predictable occurrence, so we can do some reverse mathematics and actually fix that. So this lens was a Schneider 110, pretty sure, and if on this one, at F5.6 it looks nice and sharp, this one at F let's turn on diffraction correction, and that just adds a little bit of sharpening, but specific sharpening, to counteract the diffraction that small apertures does. Now, it's not turned on permanently, because it will take longer to process your image, because it's quite a lot of heavy math going on in the background, so the processing times will be longer. So you should only turn on diffraction correction, if you've shot at small apertures. Now that small aperture could be, F16, it could be F22, it could be F11. It's very much camera dependent. So it's something that it's worth, if you shoot landscapes, or you need to shoot interiors or architecture at smaller apertures, do a quick static test of your camera, do an aperture sweep from F5.6 all the way up to F32, and see where the diffraction loss starts to come in, and then you can see how well it's corrected in Capture One, as such. Otherwise, that's all you really have to worry about for lens corrections, it's an automatic process, if you do nothing, you can be safe in the fact that Capture One is fixing everything in the background for you, if you don't like lens corrections for some reason, then up in the tool you can say disable default lens correction, and then we will do nothing to the image, unless you instruct it to. So right there, disable default lens correction.