ComfyUI Node: Luminance Stack Processor (5 Stops)

Luminance Stack Processor (5 Stops):

LuminanceStackProcessor5Stops is a sophisticated node designed to enhance the dynamic range of images by processing multiple exposures into a single high dynamic range (HDR) image. This node is particularly beneficial for AI artists who wish to achieve a more detailed and balanced image by combining different exposure levels. The primary goal of this node is to merge five different exposure values, ranging from very bright to very dark, into one cohesive image that retains details in both highlights and shadows. By utilizing advanced HDR algorithms, such as detail injection, this node ensures that the final image is not only visually appealing but also rich in detail. The automatic calibration feature further simplifies the process, making it accessible even to those with minimal technical expertise. Overall, LuminanceStackProcessor5Stops is an essential tool for anyone looking to create stunning HDR images with ease.

Luminance Stack Processor (5 Stops) Input Parameters:

ev_plus_4

This parameter represents the image captured at an exposure value (EV) of +4, which is typically a very bright image. It is crucial for capturing details in the darkest areas of the scene. There are no specific minimum or maximum values, but it should be a properly exposed image at +4 EV.

ev_plus_2

This parameter is the image taken at an exposure value of +2, which is brighter than the base exposure. It helps in capturing details in shadows while maintaining some highlight information. Like ev_plus_4, it should be a correctly exposed image at +2 EV.

ev_0

The ev_0 parameter is the base exposure image, capturing a balanced view of the scene. It serves as the reference point for the HDR process, ensuring that mid-tones are well-represented. This image should be correctly exposed at 0 EV.

ev_minus_2

This parameter is the image captured at an exposure value of -2, which is darker than the base exposure. It is essential for preserving highlight details that might be lost in brighter exposures. The image should be properly exposed at -2 EV.

ev_minus_4

The ev_minus_4 parameter represents the image taken at an exposure value of -4, which is typically very dark. It is crucial for capturing details in the brightest areas of the scene. This image should be correctly exposed at -4 EV.

exposure_step

This parameter defines the step size between the exposure values, with a default value of 2.0. It impacts the range of exposures used in the HDR process, allowing for finer or broader adjustments depending on the scene's dynamic range.

exposure_adjust

Exposure_adjust allows for additional fine-tuning of the overall exposure of the final HDR image. The default value is 0.0, but it can be adjusted to brighten or darken the result as needed.

hdr_algorithm

This parameter specifies the HDR algorithm to be used, with "detail_injection" as the default option. It determines how the different exposures are combined, affecting the level of detail and contrast in the final image.

auto_calibrate

Auto_calibrate is a boolean parameter that, when enabled, automatically adjusts the calibration of the HDR process to optimize the final image. It is set to True by default, simplifying the process for users.

debevec_exposure_comp

This parameter sets the exposure compensation for the Debevec HDR algorithm, with a default value of -8.0. It influences the balance between different exposures, ensuring a more natural-looking result.

debevec_anti_banding

Debevec_anti_banding is a boolean parameter that, when enabled, reduces banding artifacts in the final HDR image. It is set to True by default, enhancing the overall quality of the image.

Luminance Stack Processor (5 Stops) Output Parameters:

hdr_image

The hdr_image is the final output of the LuminanceStackProcessor5Stops node, representing the combined HDR image. This image retains details from all input exposures, providing a balanced and detailed view of the scene. It is the primary result of the HDR process, showcasing enhanced dynamic range and detail.

Luminance Stack Processor (5 Stops) Usage Tips:

• Ensure that each input image is correctly exposed at its respective EV to achieve the best HDR results.
• Utilize the auto_calibrate feature to simplify the HDR process, especially if you are new to HDR imaging.
• Experiment with the exposure_adjust parameter to fine-tune the overall brightness of the final image.

Luminance Stack Processor (5 Stops) Common Errors and Solutions:

5-Stop HDR processing failed: <error_message>

• Explanation: This error occurs when the HDR processing encounters an issue, possibly due to incorrect input images or parameter settings.
• Solution: Verify that all input images are correctly exposed and that the parameters are set appropriately. If the error persists, try using the ev_0 image as a fallback to ensure a baseline result.