4.4. Creative Tonemapping Techniques

BY Dieter Bethke

I live in the city named Kiel, in the north of Germany. My main assignment is consulting and sharing my knowledge in the photographic and printing community. We have a lot of water, ships, and landscape around my home base and I like to travel, mainly to northern and major European cities. To me, they are most impressive in the nighttime. So I focused on trying to create exceptional photographs around the themes of transportation, landscape, architecture, and night shots. Consequently, I got to know about capturing HDR images and spent a long time experimenting with this exciting new way to record and present high-contrast scenes.

In order to present stunning prints or onscreen presentations of my HDR images, I have to compress their dynamic range down to a level the planned output device is capable of. This process is called tone mapping, and it will be necessary as long as images have to be printed on common photographic substrates, inside newspapers and magazines at least. At first glance, it sounds like a lot of complicated work and it may seem as if we're degrading the quality of images. But how is quality of an image measured? Is it measured solely by its technical attributes? Definitely not. An image is more than "correctly" reproduced colors and shapes. It's an apparent interpretation, created and controlled by the photographer. To my personal deep conviction, the step of tonemapping a completely captured scene in HDR image formats is the key to create a unique, never-before-seen image, capable of promoting the photographer's signature style.

Tone mapping offers great potential for creative arrangements, and it gives me the ability to express myself and my impression of a certain scene using methods beyond those that photographers have been used to for quite a long time now. To my knowledge, Ansel Adams's zone system was an assimilable approach to give power to the photographer and to break free from technical limitations.

At first glance it may look a bit confusing. But in the following examples, I will introduce you, step by step, to the use of all these sliders and check boxes. I will give helpful comments about my decisions to use them the way I do so you will be able to abstract your own conclusions for future projects. I will use the following examples to show you how I overcame typical problems and made creative use of tone mapping:

• Architecture shots (main issue: inside/outside view) • Case: "Sea Cloud II - The Lounge"

• Night shots (main issue: high contrast / low contrast in one shot) • Case: "Svenska Handelsbanken at night - Stockholm"

• Panoramic landscape shots (main issue: backlight) • Case: "Queen Mary 2 in the dockyard - Hamburg"

• Dramatized shots (main issue: create an eye-catcher) • Case: "The Stockroom"

• Painterly looking images (main issue: create an artistic experience) • Case: "HaBeMa" My examples, shown on the following pages, are based on well-prepared HDR images. They were mainly shot in RAW format, with at least three—often more—exposures at 2 EV stop spacing, and then assembled to HDR using Photomatix Pro's timesaving batch-processing facility.

Let's start simply, explaining the basics a bit. The following introduction into a usual HDR/tone-mapping workflow consists of two main parts: straightforward tone mapping and some final steps within a common image editing software. Here we go.

Figure 4-54. Case: "Sea Cloud II - The Lounge"

Architecture - interior views

"Sea Cloud II - The Lounge" is part of a feasibility study about cubic panorama photography, intended to be used for online presentations on shipping companies' websites. When shooting panoramas, the photographer is often confronted with a common problem for interior shots: presenting the view through one or more windows while keeping the complete interior with all details visible and pleasing. In this case, I shot a single frame image to prove the concept of HDR/tone mapping mastering the challenge of a high dynamic range scene. If it works for this single frame, it will work for a complete 360 degree panorama. Also, the tone-mapped single-frame image could be used inside a printed catalog, for example. Actual dynamic range was captured by five exposures in RAW format with 2 EV spacing in between. This means that a dynamic range of about 12 f-stops is captured. I converted the five RAW files using Adobe Lightroom's zero'd settings and exported them into five 16-bit TIF files with ProPhoto gamut. Photomatix Pro generated an HDR image out of these five TIF files and saved it as OpenEXR.

Part 1: Straightforward tone mapping of an HDR image

I opened Photomatix Pro and loaded the HDR image, which was saved as OpenEXR before. As you can see, displaying the dynamic range of about 2710:1 overburdens a common monitor's capability (that of the print, anyway). The details in highlights and shadows seem to belost.

But a little inspection with the HDR Viewer tool (Cmd+V) reveals the opulence of captured details.

Figure 4-55. The details in highlights and shadows seem to be lost.

In this section, it will be my task to set the parameters in the tone-mapping method called Details Enhancer to create a pleasing and photographically ambitious low dynamic range representation showing all the interesting details in highlights and shadows simultaneously. The resulting tone-mapping output is LDR but will show a high-contrast scene that is printable on paper or usable for presentation on a common screen.

Let's start interactive tone mapping... with default values.

≱ Though default values are a reasonable point at which to start, they are not optimal values for each and every kind of image. Generally, scenes of the natural environment or well-known interiors benefit from lower Strength values, around 30 to 50. The same is true for landscape scenes. Even lower values may be appropriate. Values above 60 tend to give a hyperrealistic look, like a ₃D game. But that does not necessarily mean I would be afraid to use higher values for Strength when appropriate. You will see this later on in another case. For this case, I decreased Strength to 40 to get a more natural-looking amount of contrast in the resulting image.

Figure 4-56. Starting interactive tone mapping with default values.

❷ Light Smoothing influences the amount of smoothing applied to the luminance variations. Have a look at the consecutively stringed chair-backs. They are dropping shadows onto each other, making this two-dimensional image look three-dimensional, and I want to emphasize this. Therefore, I reduce Light Smoothing too because the depth of this scene gets supported by emphasizing the contrast in gradients between lights and shadows.

❸ The colors of the chairs and curtains look a little bit washed out. Raising the Color Saturation value gives more vivid colors. Lowering the color saturation creates more muted colors, which might be appropriate with more technical scenes. A value of about 60 fits well for this lounge scene, in my opinion. I like the warm and colorful look of these comfy lounge chairs hit by rays of friendly sunbeams.

❹ Luminosity controls the compression of the tonal range in general. Moving this slider to the left most of the time gives a more natural look. Moving the slider to the right boosts visibility of details in the shadows and brightens the image. I decide to set it to +3 because I want to emphasize the light of the beautiful morning in this well-lit scene a bit.

➀ White Clipping and Black Clipping directly control how much image values at the upper and lower end of the histogram are mapped to pure white or pure black in the resulting image. They are similar to the black point and white point sliders in Photoshop's Levels dialog. In this case. adjusting Black Clipping to 0.50% kicks in a reasonable amount of global contrast, enhancing structures and shadows to a preferred level. And keeping White Clipping at 0.25% preserves the specular highlights of the reflection in the polished wooden ceiling.

➁ Because I want to process this tonemapped image further, I choose to output it as a 16-bit TIF. Doing so gives more leeway for useful manipulation in image-editing software afterward by keeping as much valuable information inside the uncompressed or lossless compressed TIF file format as possible. Up to this point, I optimized the parameters accord ing to the preview image. To start the tone-mapping process I have to hit the OK button. Processing the original high-resolution image in the background of the tone-mapping window takes some seconds.

➂ As mentioned in the preceding step, I save the tone-mapped result as a 16-bit TIF and will hand it over to my favorite image editing software capable of 16-bit images.

Part 2: Finalizing the tone-mapped image with image editing software

To me, this means opening the saved 16-bit TIF file in Adobe Photoshop and applying some final image enhancements—no wild stuff, just some common basic tasks to prepare the image for presentation.

❶ I apply a soft S-curve to increase the global contrast visually. To do this in a nondestructive way, I just apply a curves layer on top of the tone-mapped result.

❷ As I am already satisfied with the framing and the appearance of the image, I just have to duplicate this view and apply some appropriate sharpening to finally prepare the image for presentation.

❸ Presentation on-screen almost always demands that the image be converted to sRGB....

❹ ...reducing the bit depth to 8-bit mode and saving as JPG.

Following this first case, you are now familiar with the basic steps for creating an HDR/tonemapping presentation. The workflow consists of two main parts: tone mapping and finalizing the image. I introduced you to the major parameters of Photomatix's Details Enhancer and the crucial finalizing tasks in Photoshop.

In the following cases, I will focus more on their respective special aspects, repeating some things but not everything (trying not to bore you to death) and sometimes digging a bit deeper into other aspects.

Let's move on to the next case, revealing some insights into the challenges of night shots and helpful composition in Photoshop.

Figure 4-57. Case: "Svenska Handelsbanken at night - Stockholm"

Night shots (...in the summer, in the city...) Shooting a night scene almost always involves dealing with high contrast. Light sources and deep shadows inside the frame are responsible for maximum contrast, though they cover only small areas inside the scene. On the other hand, most parts of a night scene are dimly lit, showing only medium contrast and tending to hide interesting details. Also, night shots require long exposure times, which introduce sensor noise to the source images. Fortunately, I can overcome these obstacles nowadays with an advanced shooting and processing workflow. It consists mainly of capturing an HDR image and tonemapping it, using a tone mapper that offers widely adjustable enhancement and preserves local contrast. The following HDR image was created out of five shots, but this time using 1 EV f-stop spacing in between them because merging a higher number of shots helps to smooth out noise. While I overexposed the shadows, I did not underexpose the lights perfectly because I will clip away the highlights in this case anyway.

Figure 4-58. This is what you see, if you open the OpenEXR fi le in Photomatix Pro again.

I merged them with Photomatix Pro's HDR generator and saved to an OpenEXR file. Let's have a look. This is what you see, if you open the OpenEXR file in Photomatix Pro again.

Part 1: Tone mapping with Details Enhancer The first part of my advanced night shot processing workflow is using the parameterizable tone mapper Details Enhancer in Photomatix Pro again. Unless I'm loading formerly saved presets, I click the Default button first when I am going to tonemap a new kind of image.

❶ I start parameterizing the Photomatix tone mapping by leaving the Strength at the default (70), which serves well as starting point for a night scene. It will be adjusted later on.

❷ The scene looks too bright for a night shot. So, taking into account the lower luminosity of a night scene, I lower the Luminosity value to −9.

❸ Color Saturation raised to 90 creates a powerful blue northern midsummer night sky and brings back the color of the illumination of the building.

❹ Light Smoothing set to +2 gives me nice luminosity gradients in the sky and the building.

➀ Lowering Micro-Contrast to 0 keeps midtones and shadows a little bit more open, which I prefer. This one and the step before are highly dependent upon personal taste.

➁ Finally, adjusting Strength up to 85 gives a well-balanced contrast all over the image.

➂ The next step is to check noise level with the Zoom tool (click on the image to get 100% view) and adjust Micro-Smoothing to a value that will take care of optimum balance between low noise and preservation of fine details. I used to check at least two positions in the image. In this case, I decide to take a close look at the sky and raise Micro-Smoothing until eventually the noise disappears. Then I check a part of the image that shows the veneer and contains fine details and lower Micro-Smoothing until no degradation in detail is noticeable. Finally, for Micro-Smoothing I choose the value in between the setting used for lowest visible noise and the one keeping the finest detail. With this image, 5 is fine.

➃ To bring back the common characteristics of a night shot (high apparent contrast), I like to use the White and Black Clipping sliders. White Clipping provides specular highlights and gives good control over intentionally burned-out light sources, while Black Clipping mainly raises apparent contrast and blocks out some noise in the deep shadows. I decided to use 0.35% for White Clipping and 0.60% for Black Clipping to accentuate the look of a night scene but not lose too much information at both ends of the histogram.

➄ Saving settings as an XMP file is always a good idea so you can make use of the same settings later. Maybe you will want to write a tutorial like this one or simply to run a batch of similar scenes through the batch-processing facility in Photomatix Pro, for instance.

➅ Again, the final step of the tone-mapping part is saving the image as a 16-bit TIF and handing it over.

To go on with image editing, I open the tone-mapped result in Adobe Photoshop.

Figure 4-59. There are still some open issues to cover:

Part 2: Composing in Photoshop

In the second part of my advanced night shot processing workflow, I have to deal with common issues of 8/16-bit LDR images because the tone mapping boiled down the HDR image into a normal LDR image from the file's and data format's point of view. Though I can see a lot of apparent high contrast and details in light and shadows, this gives me the advantage of using my favorite image editing tool to work on the last odds and ends. I prefer to work in 16-bit precision, so the adjustments necessary will do no visible harm to the appearance of the image.

As you can easily see, there are still some issues to cover:

The solution to A: To gain global contrast, I just apply a curves layer, making use of a soft S-curve.

The solution to B: To get rid of the visible artifacts in the lower-left corner of the tone-mapped result, I have to create an additional layer inside Photoshop containing a spare image capable of replacing the disturbed areas. Usually, to create such a spare image, I like to create an exposure blending out of the set of original exposures by using, for example, H&S Adjust in Photomatix Pro, excluding the one or more exposures that introduce the unwanted artifacts. Then I put this spare image as a layer on top of the tone-mapped image inside Photoshop and use the layer masking feature to show only the parts needed to repair the disturbed areas of the tone-mapped image. This technique I used for the "Fridays" image, you will see later on in the showcase following the tutorials. In this special case of the shot of the Svenska Handelsbanken at night, there were too many cars driving through the frame and the traffic lights kept changing when I was capturing the LDR shots. Unfortunately, I failed to recognize these problems on location. Otherwise, I would have repeated the shots several times and selected the exposures that fit my needs best later on at home, discarding the scrap. But I missed the chance to take multiple sets, and so it was impossible to create the exposure blending mentioned above from a set of well-selected exposures. Fortunately, the second longest exposure of my one and only captured set is not showing the interference artifacts and matches as closely as possible the luminance level of the tone-mapped result. So I decided to use this single exposure as an additional layer and masked the unneeded parts of it. To paint a layer's mask, I use a relatively big, soft-edged airbrush at 50% opacity (or a pressure-sensitive stencil on a professional pen tablet).

Figure 4-60. The solution to A.

Figure 4-61. The solution to B.

Figure 4-62. The solution to C.

The solution to C: In order to straighten out the building and crop to a well-proportioned clipping, I first duplicate the layered image (reducing down to one layer) and then use the Transform → Perspective and Distort tool.

Finally, the image gets scaled and sharpened appropriately for the planned kind of presentation. As a rule of thumb, sharpening for print deserves higher values than sharpening for screen presentation.

In this case, you see an advanced combination of HDR/tone mapping and layered composition of an exposure blending in Photoshop to handle image artifacts. With this night shot case and the former one, you are well prepared for typical tone mapping and presentation tasks. In the next case, I will comment on a more advanced and specific subject: enhancing panoramic photography.

Panoramic images - even more impressive with HDR/tone mapping

If you are going to shoot a panoramic image, it's hard to avoid getting the sun or any other direct light source into the frame, resulting in a very high contrast. On the other hand, back light can give dramatic and very interesting shots. You just have to deal with the challenge in an appropriate way.

Figure 4-63. Case: "Queen Mary 2 in the dockyard-Humburg"

On one of those special November evenings, when the Queen Mary 2 was being renovated in the dockyard of Blohm+Voss in Hamburg, I assembled my tripod at a position that would give me the right viewing angle and decided to wait until the sun set exactly behind the tower. While waiting for the right moment, I took some test shots and optimized the shooting workflow and exposure settings. I also spent some time talking with some photographers taking images at the same time at this location. Sounds a little bit like going fishing!? And yes, it was a pleasure to take the exposures I needed and enjoy this darkening orange evening sky over the impressive industrial scenery. With this warm feeling and vital impression in my mind, I went home and could not wait to process the recorded exposures. And I wanted to create a panoramic image, offering the impressive experience of this situation to others. Finally, the tone-mapping workflow proved it was the right kind of tool, giving me the necessary latitude and influence.

Most of the time when people look at the result for the first time, they say, "Wow, that looks tremendous. So many details in there, and this impressionistic look. But you surely did a lot of work retouching the color of the sky and composing the tower into it using several layers and masks, right?" And that's usually the point when I start talking about HDR imaging and explain taking several exposures... Well, you have already read about the basic techniques, so I don't need to go into details again. I will say that I took six overlapping frames to stitch this panoramic image, each consisting of three exposures separated by 2 EV. And no advanced Photoshop layers composition was necessary to get this final result.

The most challenging obstacle within this project had been the cranes. It took six minutes to take the shots I finally used, and the cranes kept moving constantly. In my first tone-mapped version of this image, I had to retouch them in Photoshop to cover the ghosted areas. But while writing this, I created a new, second version using Photomatix Pro's brand-new ghost removal feature within HDR generation. This ghost removal function is a great improvement, alleviating a lot of precious time spent on retouching. This means I can afford to spend more time on more creative image enhancement tasks, like dodging and burning selective areas. But let's start at the stage of tone mapping first.

Part 1: Tone mapping

❶ As usual, I start by opening the HDR file in Photomatix Pro and start tonemapping with default values.

❷ To intensify the colors, especially the orange sky, I increase Color Saturation to 65. Usually I keep it lower for landscape photography, but this one should get a strong and impressionistic appearance.

❸ Raising Luminosity slightly to +3 emphasizes the glow around the tower a bit and opens up the shadows.

❹ The digital camera used for this project tends to introduce noise, so I have to engage micro-smoothing to smooth out noise but not too much detail. Using the 100% crop view, I check different settings and determine a value of 5 will do the job.

➀ Finally, I adjust White and Black Clipping and start the tone-mapping process to create a 16-bit result and save it as a TIF. Further processing will be done in Photoshop.

Part 2: Final steps in Photoshop

❶ As in the previous case, I apply a soft S-shaped tone curve to increase global contrast and brighten the midtones slightly.

❷ With a big soft-edged brush, I apply some selective dodging to the brighter parts of the ship's superstructure and the clock face. The shadows at the stern, bushes, and quay walls get burned the same way. I do this very gently with a maximum of 5% exposure and several strokes in order not to overdo but to pronounce the points of interest. Using the Clone Stamp and Healing Brush tools, I removed some spots in the sky, maybe generated by flying birds.

In this part, you have seen how to handle tone mapping of a panoramic HDR photograph captured as multiple frames at twilight and emphasize selective parts of the image by manual dodging and burning. At this point, I would like to offer you the opportunity to compare how the image would have looked with only one exposure directly out of the cam versus the improvement achieved by HDR/tonemapping workflow. I put them side by side so you can decide for yourself whether the result is worth the effort.

Though I enhanced complexity and expression throughout the first cases—especially this case—they present a natural-looking result of HDR/tone mapping. At least this was my intention. In the next tutorials, my examples will get more expressive and artistic. Please have a look.

Figure 4-64. Out-of-cam image

Figure 4-65. Tone-mapped HDR image

Figure 4-66. Case: "The Stockroom"

Photography between hyperrealistic painting and comic strips

The folks at a German magazine about image editing topics asked me to create an eye-catcher for their article about HDR imaging, showing the creative power of tone-mapped images. We agreed that an everyday scene presented in a totally uncommon look would do the job. The photographed scene should offer a lot of detail and "contrasty" lighting.

Within the essential steps in postprocessing, I have to add to the image more details, saturated colors, harder edges, and, last but not least, a higher local contrast without loosing details in highlights and shadows. Again, similar to "Sea Cloud II - The Lounge", the arrangement of objects inside this scene, casting shadows onto each other, creates the virtual depth of the image. So emphasizing shadows will emphasize the impression of depth and make it look more 3D, while saturated colors, hard edges, and high contrast will remind the observer of a comic strip. Together with the underlying photography of real-world scenery, it creates an eye-catching image that I call something in between hyperrealistic painting and comic style. I am aware that some parts of the audience will deprecate this style, and I am not recommending that anyone do this all the time. But please take into account that there is no such thing as wrong or right in the arts. What's important is whether you are satisfied with what you are creating. And if you are lucky, you will find more people that like what you are doing than those who dislike it.

Figure 4-67. I found this type of scene inside a small stockroom and took my shots using a wide-angle lens.

Figure 4-68. Starting the tonemapping.

Part 1: Tonemapping the high-saturated color version

That said, let's have a look at the postprocessing. The tone-mapping part in this case conzists of a twofold approach: First create the colored version, making it the main part of the resulting image, and then create a lights/shadows map.

❶ Starting with default settings, the first step to create the colored main part is to raise the Strength value from 70 to 100. I want to get the maximum possible effect this time.

❷ Raising Color Saturation to 75 creates the intended saturated colors. An extra portion of the details is preserved by lowering Micro- Smoothing to o. Lowering Light Smoothing to −1 gives more accentuated lights and shadows.

❸ By using the maximum value for Luminosity (+10), I open up the shadows and intensify colors and local contrast. Though the image gets blurred, it's not a problem as it will be fixed by the additional lights/shadows map I will create later on. Looking at the impact this step has, I reset Light Smoothing to o in order not to overdo at this point. Adjusting the settings for White and Black Clipping to achieve a reasonable amount of global contrast is the final task for this first part of the postprocessing. After hitting the OK button, I save this colored tone-mapping result as stockroom_01 .tif. It will become the background layer in the finalizing Photoshop composition of this project.

Part 2: Creating the lights/shadows map using tone mapping with different parameters

This map will become an additional layer later on in Photoshop, enhancing the edges, highlights, and shadows.

❶ In order to create a black-and-white representation out of the colored version, I have to lower Color Saturation to o first.

❷ In this step, I want to get deeper shadows and accentuate the lights. Therefore, I lower Luminosity and Light Smoothing to the minimum (−10 and −2).

❸ Prior to saving the final stage of this lights and shadows map as a TIF, I add a little more "punch" to it by raising Black and White Clipping to the maximum. Now the areas of deep shadows and highlights are well defined. This will come in handy when the project is finished in Photoshop, which is the next part.

Part 3: Composing in Photoshop

❶ Opening the saved stockroom_01.tif in Photoshop and applying a curves layer gains overall contrast.

❷ At this stage, I observe that the camera's white balance was a bit off when shooting, but it's no big deal to correct it now using the same curves layer by activating and pointing the midtone eyedropper to a neutral midtone or light gray area inside the image. I like to do it by using an adjustment layer.

❸ Now I will load the prepared lights/shadows map file (stockroom_02.tif) and put it as a layer on top of the colored layer (Shift+click the layer's icon and drag and drop it onto the open stockroom_01.tif).

❹ Selecting Hard Light as the layer mode and adjusting the opacity of the top layer to 45% adds the intended final definition of hard edges and accentuated lights and shadows, covering the blur of the colored version.

➀ As this is the final state, I want to save the composition as a PSD file, including all layers. This means I will have an unaltered version at hand for later—not-yet-known—usage.

Please remember always to include the information about the working color space you used by embedding the color profile.

That's it. As you have seen, to create the above image, I mainly used a twofold HDR/tone-mapping process and combined it with blended layers in Photoshop. The result is an accentuated and detailed image with graphical look. In contrast, the next case will show how to abstract details and apply a painterly look.

Painterly style

When we think about an artist painting a landscape scenery in oil or watercolor, for instance, he has to reproduce his impression of the original high-dynamic-range scene onto low-dynamic media, namely, the canvas covered by painted colors. His eyes are capturing the high-dynamic-range scene while his brain is able to convert the observed light and colors into directives that tell his hands how to mix the primary colors and where to place the brush to paint them onto the substrate. To me this sounds like a natural kind of tone mapping, and therefore, I am not surprised when I get results that remind me of a traditional painting when I use tone mapping on an HDR image in a certain way. One of the first things I tried with tone-mapped results was to make them look even more like a painting, including printing them on canvas using fine art printing methods.

To create images that look like a painting (you probably guessed it already), I use the two-step processing of tone mapping within Photomatix Pro and then finalize it in Photoshop. In the tone-mapping part, I will create the basic implementation of painterly-looking light distribution and colors, so the final steps in Photoshop will consist mainly of retouching where necessary and imitating typical painting strokes.

Part 1: Tonemapping with high saturation, low-light smoothing and high strength

❶ I load the HDR image and start tonemapping with the default settings. This time I keep Strength at 70 to get a fair amount of dynamic compression. This lays the foundation for the painterly look. The colors of the original shot taken on a misty November morning are muted. Increasing Color Saturation to 70 facilitates more vivid colors, while lowering Light Smoothing to o pronounces the diversion of light and adds more eagerness to the scene. For a smoother look and a higher level of abstraction, I raise Micro-Smoothing to 10. Details will be eliminated by the artistic brush later on anyway.

Figure 4-69. Case: "HaBeMa"

❷ In the last step prior to saving the files as a 16-bit TIF, I adjust White and Black Clipping to gain more overall contrast. The basic tasks a painter would have done painting this scene— namely, abstraction of details and dramatizing lights and shadows—are already done at this point. Finalizing in Photoshop will only correct some unavoidable distractions, like the pole in front and the branches at the left edge, and apply some artistic brush strokes.

Part 2: Finishing in Photoshop

❶ Using Photoshop's Clone Stamp, Healing Brush and Patch tools, I retouch and eliminate the distracting pole and the branches at the left edge. I prefer to do such destructive editing on a cloned layer in order to keep the master layer as backup. You never know.

❷ In order to apply some artistic brush strokes from the filter gallery, I have to duplicate the retouched version and reduce it to one layer. The Dry Brush and Watercolor filters demand 8-bit mode.

❸ After boiling down to one layer and 8-bit mode, I start the filter gallery and select Dry Brush as the first approach. By simple trial and error, I compare different settings and finally dial in 1/8/1 as satisfying parameters.

❸ As second option, I give the Watercolor filter a try with the settings 12/0/1 and compare the result to the Dry Brush result. It's definitely a matter of taste, and in this case I prefer the watercolor look. Printed as a fine art print on watercolor paper, this will look just great. This last step is only a quick overview about finishing a tone-mapped image with artistic brushes because the focus of the chapter is tone mapping. Usually, several layers with different levels of detail and layer masking will be used to refine the process and apply different levels of abstraction to different parts of the image. Or I would make use of software simulating natural painting strokes with a stylus and a pen tablet.

Within this last example, I use individual parameterized tone mapping for basic abstraction and Photoshop's artistic filters to finish. Using an artistic filter out of Photoshop's filter gallery does not necessarily make you an artist, but I think my last example shows clearly the impact and potential of combining simulated natural media painting and tone mapping. Through HDR capturing and tone mapping, photographic artists are now able to achieve the same results as painters by using abstractive levels or being as precise as possible in reproducing the real view. As you have seen, creating a satisfying image by tone-mapping a high-contrast scene is not a "push one button" task.

Some photographers at the intermediate and beginners levels might think it is adequate to use an automatic tone mapper or the default values of parameterizable ones. However, I suggest that you invest some time looking at the parameters and playing around with them. Make your own experiences and discoveries. Different kinds of images deserve differ ent settings, and tone mapping is a subjective process. Why should we waste the potential gain in photographic quality and creativity a good parameterizable tone mapper with a reasonable graphical user interface is offering us? Please remember, there is no objective right or wrong in photography and other arts, but the photographer is solely responsible for the subjective results. And speaking for myself, I wouldn't want to pass this responsibility on to a fully automatic tone-mapping algorithm. So I highly recommend making the effort of an individual approach.

Hopefully you enjoyed my walk through some of the creative possibilities HDR/tone mapping offers to us, and maybe you became inspired, at least a bit. All in all, you have a working toolbox at hand now and may arrange it according to your own style and workflow. To me, it is always a satisfying moment when professionals or seasoned photographers take a look at some of my images and tell me, "This cannot be done with one shot. How did you do it?" On the following pages, you will find a selection of images created using the same techniques as explained in the preceding sections. Thanks for reading—now relax and enjoy.

To see more of Dieter's work check out his website www.hdrfoto.de/hdribook/