What are the best practices for optimizing HDR workflows in digital art software?

1 Choosing the right format

Not all image formats support HDR, so you need to choose one that can store and export the full range of HDR data. Some of the most common HDR formats are OpenEXR, HDR, and Radiance RGBE. These formats use 32-bit floating-point numbers to represent each color channel, which allows for more precision and dynamic range than 8-bit or 16-bit formats. You should also avoid formats that use compression or tone mapping, as they can reduce the quality and accuracy of your HDR images.

2 Setting up the workspace

To work with HDR images in your digital art software, you need to set up your workspace accordingly. This means adjusting the color space, exposure, and tone mapping settings to match the HDR input and output. For example, you should use a linear color space, which preserves the linear relationship between light intensity and pixel value, rather than a gamma-corrected one, which compresses the dark and bright areas. You should also use a suitable exposure value, which determines how much light reaches the virtual camera sensor, and a tone mapping algorithm, which converts the HDR values to a displayable range.

3 Using the right tools

Some tools and effects in your digital art software may not work well with HDR images, or may require some adjustments to avoid artifacts and errors. For example, you should avoid using tools that rely on color thresholds or clipping, such as levels, curves, or hue/saturation, as they can create banding or clipping in the HDR range. Instead, you should use tools that work with relative values or percentages, such as exposure, contrast, or color balance. You should also be careful with tools that introduce noise or grain, as they can amplify the HDR values and create unwanted artifacts.

4 Previewing and testing

One of the challenges of working with HDR images is that they cannot be displayed accurately on most monitors, which have a limited brightness and color gamut. Therefore, you need to preview and test your HDR images on different devices and platforms, such as HDR monitors, TVs, or mobile phones, to ensure that they look good and consistent across different environments. You should also use a reference image or a color chart to check the accuracy and fidelity of your HDR images, and make any necessary adjustments to your workflow.

5 Exporting and delivering

The final step of optimizing your HDR workflow is to export and deliver your HDR images in the appropriate format and settings for your intended purpose. For example, if you are creating HDR images for a game or an app, you need to follow the specific guidelines and requirements of the platform or engine you are using, such as resolution, file size, compression, metadata, etc. If you are creating HDR images for print or web, you need to convert them to an SDR format, such as JPEG or PNG, and apply a suitable tone mapping or color grading to preserve the HDR look and feel.

6 Learning and improving

HDR is a complex and evolving field, and there is always more to learn and improve in your HDR workflow. You should keep yourself updated with the latest trends, techniques, and tools for HDR in digital art software, and experiment with different approaches and styles to find what works best for you. You should also seek feedback and inspiration from other artists and professionals who work with HDR, and share your own experience and knowledge with the community.