It's all about the details
Ellen Anon | Software Techniques | Published Oct 20, 2011
Photographers are always concerned about what’s in focus - making certain that in-focus areas are tack sharp and when using limited depth of field, that out of focus areas are pleasantly blurred. There is no shortage of advice on how to do this in-camera via careful shooting techniques. Here we will look at the ability to emphasize detail post-capture.
It's important to understand up front that the techniques covered here will not turn a blurry mess into a razor sharp masterpiece. Digital processing does, however, offer a number of options for modifying the appearance of detail.
Enhancing or suppressing detail essentially revolves around increasing or decreasing contrast within the image, whether it’s luminosity or color-based contrast. The key lies in how and where the contrast adjustments are applied. The challenge when attempting to emphasize detail is to avoid also emphasizing image noise. Care must also be taken of course to maintain a natural, believable result.
In this article I will explore techniques for enhancing detail using a single image. We’ll use tools that are common to most major image editing software as well as plug-ins from Nik Software and Topaz Labs. While there are certainly other tools available, these examples can serve as jumping off points for you, no matter which application you use.
Clarity and Definition sliders
We’ll begin with the Clarity slider, which is found in both Adobe Camera Raw (ACR) and Lightroom (LR) and the Definition slider used in Aperture. These sliders can be used to increase (or also decrease) localized midtone contrast, meaning that the effect is aimed primarily at 'flat' areas of relatively modest contrast. Furthermore, these tools seek to apply a rather gentle adjustment that avoids setting pixels to either pure white or pure black, which would actually obscure detail.
You can see this by watching the histogram change as you pull these sliders from one extreme to the other as shown in the image below. The distribution of pixels changes so that pixels are slightly shifted away from the midtones towards the extremes, which increases the midtone contrast. Visually these tools can add the illusion of increased sharpness as well as a slight saturation boost. Used to an extreme, of course these sliders can create artifacts, but used properly, they can seem almost magical.
Below you can see a single image and histogram both before and after some localized midtone contrast adjustments. No other adjustments have been applied.
|Image with no adjustments||Histogram with no adjustments|
|Image after using the Defnition slider||Histogram after using the Defnition slider|
|Image after using the Clarity slider||Histogram after using the Clarity slider|
To apply this effect to specific parts of the image in ACR or LR, use an Adjustment Brush and set the Clarity value as desired. Note that you can set a negative value for the slider and this will reduce the details. This provides the option of enhancing the appearance of detail simply by applying brush strokes with a negative Clarity value in background areas; the detailed areas, by comparison will appear to be 'more' detailed. In Aperture you can paint in the Definition adjustment wherever you like, to increase detail. In order to decrease detail go to Brushes > Blur and paint over the areas you wish to appear less sharp.
Plug-ins for detail modification
For even more control over details, Nik Software's Color Efex Pro 4 (CEP4) plug-in includes several contrast adjustment filters. Topaz Labs also produces plug-in effects that can adjust contrast. Many other tools exist, of course, but these are the ones that work for me and should give you an idea of what’s possible. It's worth repeating that any of these tools can create extremely un-natural results, but when used with a light hand, they can improve your image significantly.
Nik Detail Enhancer
The first filter I often turn to to enhance detail is Nik’s Detail Enhancer. This filter is new to CEP4 and one that I find I am using frequently. As the name implies, it emphasizes details throughout the image. Set the Effect Radius controls to Fine to bring out as much detail as possible, Normal for a moderate amount of detail, and Large to emphasize just the larger details. Which one is best depends on the particular image, but you can see how this setting changes the results in the examples below. The Detail Extractor (DE) slider is the main control or 'throttle' determining how much detail is emphasized, then you adjust the Contrast and Saturation sliders to taste. You can use the Control Points to apply the Detail Extractor just to localized areas or to temper it’s effects elsewhere. Note that in the final image I’ve used a Large Radius setting but decreased the DE significantly.
|Original Image||Detail Extractor set to Fine|
|Detail Extractor set to Normal||Detail Extractor set to Large|
|Final image, Reduced DE slider for subtly increased detail|
Nik Tonal Contrast
A potential disadvantage of the Detail Extractor is that it accentuates details throughout the tonal range. Sometimes you’ll want to bring out details not based on their size, but by their tonal value, so that you can adjust details independently in the highlights, midtones or shadows. I use Nik’s Tonal Contrast filter for that. When you first open this filter, by default the highlight and shadow sliders are set to 25 and the midtone slider is set to 50.
Sometimes this is effective but other times I find it’s a little too strong if I want to maintain a realistic looking image. By adjusting the sliders individually you can quickly and easily enhance details throughout the image. Use control points to limit the effect to specific geographic portions of the image. In the example below, I mainly opened up the Shadow Details to restore detail to the foreground. I subtly added to the midtone and highlight details to maintain a realistic look to the dramatic clouds and lighting.
|Original Image||CEP 4 Tonal Contrast|
Nik Contrast Color Range
The other Nik filter I often turn to is Contrast Color Range, to increase the awareness of various color details in an image. The sliders in this filter are a little less intuitive to use, but overall they enhance or reduce the contrast among the colors in the image by lightening a target color and darkening its complementary color. This can help isolate or blend objects and details within the image depending on their color. It’s easier to use than it sounds. I begin by decreasing the default overall Contrast slider. Next I make sure the Color Contrast slider is set to about 75%. (That way it’s easy to see what colors are being affected.)
Next I adjust the Color slider to choose the “key” color, which is the color that will get lightened. The complementary color of the key color will darken. You can make this choice based on the visual results as you move the slider since the image often will change substantially. Then I adjust the Contrast Color slider to adjust the strength of the effect, and then tweak the overall Brightness and Contrast sliders. In the example below, note the separation of colors in the foliage after applying Contrast Color Range.
|Original Image||CEP 4 Contrast Color Range|
Topaz Detail 2
Topaz Labs offers several filters that enable you to modify the details in an image. Most Topaz products share a common user interface. On the left there are various presets and as you scroll over them, the preview above changes. In the center is the image showing whatever changes you’ve applied or the initial image. On the right is a navigator and various sliders to allow you to tweak each parameter. As you hover the cursor over each slider a tool tip appears explaining the function of the slider. But often the most effective way to set the sliders is to experiment by pulling them to extremes and then scaling back, always paying attention to how the image changes.
Topaz Detail 2, is a plug-in devoted to detail enhancement or suppression. There are numerous presets for emphasizing details or smoothing out details that serve as good starting places. On the right side of the interface there are six sliders. The Small, Medium, and Large Detail sliders allow you to determine what areas are considered as small, medium or large details. A quick pull of the sliders to the extremes lets you see what this means for your particular image. The associated Boost sliders then accentuates (or suppresses) these details. Often a very light hand is helpful with the Boost sliders.
Be particularly careful with the Small Boost slider because it can aggravate any noise issues present when pulled to the right - of course moving it to the left can reduce some noise, but it may remove details as well. Topaz Detail 2 contains additional sliders to let you modify the overall brightness and white balance, as well as to protect highlights and/or shadows, modify saturation and deblurring. As you can see in the example below, it’s possible to increase details selectively such as in the raccoon’s fur by adjusting the detail size sliders.
|Original Image||Topaz Detail 2|
One of Topaz Labs most popular filters is Topaz Adjust, which offers control over of exposure, colors, noise suppression and details in one interface. I find that the three presets directly pertaining to Details (Small Details, Mild Details, and Detailed) are too strong for the more realistic looks I usually prefer, but you can use them as a starting point and then tweak the sliders in the Detail section on the right side of the interface, or you can go directly to those sliders when you open the filter. The Strength slider controls the amount of detail enhancement, while the Boost slider controls the amount of small detail enhancement.
The Threshold slider lets you specify how much variation there needs to be among pixels before it’s considered a detail. The farther to the right you set the slider, the more variations that are considered to be details. The Radius slider lets you further refine the detail enhancement. The farther to the right the slider, the larger the variations that are considered to be details. As with all sliders, visually adjusting them to extremes often makes it easier to see the effects and thus to set them them properly to give the desired effect. In the image below, I’ve adjusted the sliders to increase the detail in the rabbit’s fur, but as you can see, other parts of the image show increased details as well. To limit the effect to the rabbit, I’d need to create a selection and use a layer mask.
|Original Image||Topaz Adjust|
Of course the more small details you bring out, the more likely you are to also reveal noise, so Topaz Adjust also contains two approaches to noise reduction, one faster and the other (the option to Use Topaz Denoise) more refined. In addition, sometimes checking the option to Process Details Independent of Exposure sometimes helps with halos and other artifacts. Although Topaz Detail 2 provides more finely tuned adjustments for controlling the appearance of details, Topaz Adjust 3 can often do the job.
Topaz Labs also offer Topaz InFocus which is a slightly different type of sharpening program intended to enhance detail. I find that although the program can be helpful to decrease some types of blurs and thus enhance details, it’s extremely easy to accidentally add artifacts with this program, especially when you check it at 100% magnification.
Tip: It’s a good idea to check your settings with any of these tools at 1:1 magnification to be sure that you’re happy with the results before applying them. Viewing the image at 100% magnification lets you more easily see any artifacts that were created as a side effect of enhancing details.
Some HDR programs, such as Photoshop’s HDR Toning (found under Adjustments), Nik Software’s HDR Efex Pro, and HDRSoft’s Photomatix can be applied to a single image to use those tools to expand the range of visible details. Same image HDR processing can be a very effective way of revealing considerably more detail than was first apparent in an image but it may be challenging to maintain a realistic looking result. Often the final result may be somewhat surrealistic as shown in this image of Fly Geyser.
|Original Image||Surreal increased detail in Photomatix|
A major difference between the Nik Software CEP4 filters and those from Topaz Labs is that Nik’s controls enable you to choose whether to focus on applying the affect separately to highlights, midtones or shadow areas, or to color contrasts, or to size of details to be enhanced, whereas the Topaz tools focus on the size of the details to be modified. This is a distinction that can make a major difference depending on the image and may determine which tool will be the most effective. You may find that you prefer one tool for some images and another approach in other circumstances. Most companies allow you to download fully functional demo versions of their software to allow you to decide what works best for you.
All of these filters can be applied to the entire image, but the Nik products can easily be applied to just a localized area by using control points. (Control points are a standard part of all Nik software and take the place of time consuming selections and layer masks.) To apply Topaz filters, as well as other HDR processes, locally you need to apply the filter within Photoshop or Elements on a duplicate of the background layer and then use a layer mask. This is a bit more time consuming but is certainly doable.
Although digital processing now offers a variety of ways to quickly enhance the details in your image, you still have to use good photographic technique and focus accurately. None of these approaches can create a masterpiece from a sloppy out of focus shot!
* For full disclosure, I am a member of Nik Software’s Team Nik. However I write about the products I use and use those that are the easiest and yield the highest quality results for me. You may prefer other software to achieve similar results.