Welcome to the grand finale of my four part photo-processing tutorial! So far we’ve covered how to understand your histogram, basic image processing, and an explanation of the tone curve and the HSL panel. This final portion will cover the Details Panel in Lightroom and Adobe Camera RAW which contains the Sharpening tools and the Noise Reduction tools.
A quick word about sharpening. The Unsharp Mask filter in Photoshop is as old as the program itself. Every and all digital files require some amount of sharpening when you process them (JPEGs are sharpened in camera, usually over-sharpened, but all RAW files need some sharpening applied). For reasons regarding how terrifyingly long I don’t want this article to be I won’t get into the structure of Bayer Matrices and the flaws inherent to digital sensors. Just take my word for it: sharpening can really bring out a lot in a photo, even though you might think it’s a very small change.
Similar to the Clarity tool, sharpening is better understood as “edge contrast.” When you apply sharpening to a photo, the processing program is running through all the pixels in the image and finding all of the edges at which dark pixels come into contact with light pixels. When you increase the amount of sharpening the light pixels are getting lighter and the dark pixels are getting darker, thus making these edges appear “sharper” and more define
- Amount: see above. How much sharpening will be applied, i.e. how bright the light pixels will be made and how dark the dark pixels will be made.
- Radius: how many pixels outside the line where light and dark meet will be brightened or darkened? For portraits I usually set this at about 1.0-1.5 so that wrinkles or creases in a person’s face don’t become too extreme. If you’re doing a landscape, say one where there are a great many edges like a pine tree covered hill or a busy city street, I usually set this at about .5-.7.
- Detail: sort of a fine tune for your Radius slider. I generally set this at a number about 10 below the Amount slider.
- Masking: this slider ensures you’re only sharpening actual edges, instead of the entire image; I usually set this around 35, but if I have a picture of, for example, a hairy dog with lots of edges, I’ll set it at around 45. These differences are difficult to see online, but you may be able to notice how the details of this scarf are more defined and seem, well, sharper.
Unlike sharpening Noise Reduction is not necessary on every digital photo. On most DSLRs you won’t be needing any Noise Reduction until you hit about ISO 1000 (and on compact cameras I’d say maybe about ISO 400, depending on the model). But what’s great about it is that it can make what was an unusable ISO 3200 photo totally clean and noise free. I shot at ISO 3200 for the entirety of fashion week; on the first day I created a preset for sharpening and noise reduction at that setting and it seriously sped up my processing for the entire week. Here’s an example of a 100% crop of a photo shot at ISO 3200.
- Luminance Noise Reduction: very simply, Luminance Noise is created when there is not enough light for the sensor to determine how bright a given pixel is and it is much more prevalent than Color Noise which we’ll get to soon. You will usually be applying more LNR than CNR, depending on the ISO. For ISO 3200 I usually set it at about 30-35-
- Detail: applying LNR can cause a certain sort of smearing or blurring and the Detail slider corrects this, maintaining details and edges where LNR blurs them. It’s default setting is 50 and I usually don’t need to set it at more than 59 or 65 (at ISO 6400 say maybe 70ish).
- Contrast: similiar to the Detail slider, Contrast is used to correct the issues with LNR. Raising the contrast slider will bring contrast back into those blurry areas. It’s a very small change and I usually don’t go above about 25.
- Color Noise Reduction: very simply, Color Noise is created when there is not enough light for the sensor to differentiate between red and green color values, thus creating those red/green blobs you see when you have a noisy photo. It’s default setting is 25 and even at ISO 3200 I only raise it to about 30-33. The default value of 25 will be fine for all ISO values up to 3200.
- Detail: same as the detail slider above, but it applies to the CNR instead of LNR issues. I very rarely touch this one unless I’m shooting at ISO 6400 and have my CNR set at 40 or above.
Here is the final product with all noise removed and all detail maintained. For the settings I used here and for most ISO 3200 shots, see the still of the sliders above:
Like the rest of photo processing all of these things you sort of need to season to taste until they look right for you, there’s no single correct way to do it, but there are many ways to do it incorrectly or to overdo it and get poor results. Always use your best judgement. Feel free to ask any questions you might have these (because they definitely are pretty technical and complicated) or if you’d like to know what presets I’ve made for the ISOs I shoot at most often.