Post-Processing / Denoise
Actions
- denoise [m] : Noise reduction tool.
If you find yourself using this, you might want to go back and next time include some more overexposed shots when bracketing! The batch tool should result in a shot with no noise, so this is just a fix for not being able to shoot the lighter exposures.
The denoise [m] action is designed to remove digital noise while retaining maximum detail. The action will use a merged copy of the image, so make sure to run the action with the topmost layer selected. This action is built for batch processing, and is very computationally intensive. Run time will vary based on computer speed and image size.
This action is designed to be run after development but before doing any sharpening. It results in a layer with an empty layer mask which can be used to tweek the amount of noise reduction by hand if desired.
Massively over-sharpening a denoised image might uncover a light fine texture in flat areas of the image which used to have a large amount of noise. This texture is the result of the denoise algorithms trying to restore detail under the noise. The Layer Mask on the sharping layer can be used to reduce the sharping in areas that show any fine texture.
Below is an example of four processed 100% crops from the following image. The large contrast adjustments and lack of a full set of bracketed images resulted in some objectionable noise.
Observe the difference between the image before denoising, after denoising, and after sharping the denoised image. Notice that in some areas, the image actually looks sharper after removing the noise. Unlike other noise reduction tools, denoise does not produce smearing and blurring artifacts.