How to adjust the tone mapping for the HDR photo

When you are looking at the surroundings, perhaps some areas are very bright while some areas are very dark. The total range of values from the darkest areas to the brightest areas in a scene is defined as the dynamic range. Human eyes can adjust properly to see the details in these areas, but most photo capture device lacks this capability. If you take a photo of such a scene, the details in the brightest area are overexposed and the details in the darkest area are underexposed. Even though the dynamic range can be captured by the capture device, it can't be displayed using conventional display equipment. If you have HDR photos that are not allowed to be displayed, tae advantage of tone mapping. Tone mapping clips the extended dynamic range and compresses it into a range that can be displayed on the screen. There are plenty of photo editor software programs that allow you to use the tone mapping technique. Most of them are too complicated and not suitable for fresh hands. If you are a beginner in this field, please continue reading this article. I will introduce a piece of easy-to-use photo effect software and show you how to adjust the HDR tone mapping with it.

Photo Effects

Photo Effects by Vertexshare is a straightforward application you can use to manipulate the effects of your photos.

The window of this program is divided into three panels. A collection of predefined effects are located at the left-side panel. The middle panel takes up most of the window. It is for you to compare the differences between the original photo and the changed photo. The right-side panel is composed of a series of parameter sections. Here you can adjust the photo exposure level by tweaking the exposure compensation, exposure compression, lightness, saturation, and contrast. You also can adjust the shadows/highlights, tone mapping, dynamic range compression, and sharpening. Some other adjustments you can make include local contrast, white balance, vibrance, channel mixer, soft light, and vignette filter. You are also given the possibility to reduce the noise level.

On the whole, Photo Effects is a versatile photo effect enhancer app for you to apply basic adjustments to your photos. Due to the intuitive options and user-friendly interface, it can be easily handled by both novices and veterans.

Now, let's dive right into the part of adjusting the tone mapping using this tool.

How to adjust the tone mapping for the HDR photo with Photo Effects

Step 1.

• Throw your photo onto the working space. Or click on "File"->"Add Photo" to import your photo into the program.

Step 2.

• Go to the section of "TONE MAPPING" at the right panel. Click on the "TONE MAPPING" button to activate the function of adjusting parameters. The parameters here are the strength, gamma, edge, scale and reweighting iterates. Drag the slider to adjust each of these parameters to fit your needs. If you want to discard the changes you make, click on the "Redo" button in the top menu to discard changes. Below are the explanations of these parameters in the section.

Strength

This parameter is for controlling the overall effect of tone mapping. It is used to keep the average luminance of the photo. Increasing the value will raise the highlights and lower the shadows to prevent the underexposed look. Conversely, decreasing the value will lower the highlights and increase the highlights to prevent the washed-out look.

Gamma

This parameter is for adjusting the midtones. It moves the action of tone mapping to the lowlights or highlights. Increasing the value will darken the overall photo.

Edge stopping

This parameter influences the sensitivity to edges. The higher the value is, the more likely an illumination change will be counted as an edge.

Scale

This parameter defines the difference between local contrast and global contrast. The higher the value is, the larger the detail to be boosted needs to be.

Reweighting Iterates

This parameter is to deal with the cartoonish appearance and soft halos which tone mapping might produce. Increasing the value will fix these problems.

Step 3.

• When you are satisfied with the adjustments, press "Export Photo" or click on "File"->"Save As" to export the image to a desired location.

An alternative to Photo Effects for adjusting the dynamic tone mapping

HDR Darkroom 3 is a professional HDR app that comes with the feature of tone mapping to help you to create spectacular HDR photos. Follow the steps below to adjust the dynamic tone mapping with this all-in-one photo editing tool.

• Take 3 differently exposed photos by changing the shutter speed. This will ensure you cover the full dynamic range.
• Launch the program and press "New HDR" at the top-left corner of the main window to import the bracketed photos into the program.
• Check the HDR merging options as you want and click on "OK" to continue. When the process is done, you will get an HDR photo.
• Go to the right pane and press the "Advanced" tab. You will see the "Tone Mapping: option.
• Here you can adjust two parameters, radius and strength. Radius is for differentiating the local and global contrast. Strength is for adjusting the local contrast level. Drag the slider or type the values to adjust the parameter.
• Click on the "Save" button on the left-hand toolbar. Specify the destination folder and choose the desired file type. Then, click on "Save" to save the photo to your hard drive.

Summary

Tone mapping is a technology for compressing an extended dynamic range into a range that can be displayed on conventional display devices. If you have such a need, give the tools mentioned above a shot. With the help of them, you can tone-map your HDR photos without any hassle.