Noise

Noise Reduction is a first step in enhancing the image. All of the following operations like sharpening and color balancing increase noise and make it more noticeable. It is important to clean the noise from the image at the very beginning.

Even bright images shot on a sunny day contain a lot of noise so please do not skip this step without good reason.

While on Noise Reduction Tab you can set the zoom level from 25% to 400% by using the thumb wheel on your mouse ().

The less you zoom, the more pixels are processed and the longer at takes the preview to update. The whole image will be processes when you switch on Save or Retouch tab.

Please note that the noise reduction filter is not applied on the tabs where downsized images are used for faster preview (Brightness, Color, Distortions, Frames tabs).

To apply all filters and see the final result please switch to the Save tab. If you like the result, you can save it and process the next image. If you don't, you can always switch back to the filter, fine tune the settings and get an updated result.

The program remembers the settings for each file you processed. So when you open the file again, the program recalls the most recent settings for this file. You can also save the file settings manually (Menu->Settings->File Settings).

Controls

The Load settings select box lets you choose one of the predefined settings for this tab. You can also save your current settings for future use.

The Enable noise reduction check-box lets you skip this processing stage completely. If this box is not checked, all other controls on this tab are disabled.

The Noise level, Highlights, Shadows sliders. These three controls define the noise level in the medium, light and dark areas of the image.

Noise level is measured in an abstract absolute value from 0 to 200. You can use this value to compare noise levels in different images. The program automatically detects the level of noise in highlights, midtones and shadows. If you think the program acts too aggressively, set a lower value of the noise level. If you want to clean a particular area (e.g. sky), use an appropriate slider (Highlights for the sky, Shadows for the dark trees).

Please note, that your settings will be saved automatically and applied to all of the following images. To reset the settings use the Reset ()button. It sets all sliders to the default (automatically detected) values.

The Radius sets a smooth degree. Higher values result not only in a cleaner image but also in artifacts on edges. Lower values preserve details but also show more noise.

The Chroma defines how strong the noise in chroma channels is if compared to a reduced luminance of a channel.

The Method - select an algorithm which gives the best results on your particular image. For images with low noise, the "Standard" method is good enough, for very noisy images try the "Aggressive" method. These methods use completely different algorithms.

The Noise Reduction slider defines how much of luminance noise should be removed. In many cases the image looks more natural if chroma noise is completely removed but a part of the luminance noise is left. Completely denoised image may look too "plastic".

The Reset ranges (...) lets you delete all color ranges, which you have added to increase/decrease noise reduction in certain areas. Undo button removes only the last color range. For more details see description of pop up menu commands in the next section.

The Noise Map button lets you switch to a special mode, where intensity of a red color corresponds to the degree of noise reduction. You can use this map to check if fine texture areas are not considered to be noise. It is also a good tool to see effects of the noise reduction equalizer and color ranges.