Some scanners come with Digital ICE technology. Digital ICE automatically removes surface defects, such as dust and scratches, from a scanned image. Digital ICE technology works from within the scanner, during the scanning process, but gives users little or no control over the process or the outcome. SilverFast’s SRD feature does.

The SRD tool sits in the vertical toolbar at left of the preview window. It is a Red Cross icon that opens a dialogue window when clicked. The SRD process starts with a new prescan of the image. The preview will have an overlay grid in red and a yellow-bordered Navigator area.

For optimum recognition of artifacts SilverFast uses two different methods. The first is the regular dust and scratch removal and the second one is the removal of linear artifacts. These work with parameters with similar names, yet have different effects on different artifacts.

There are some interesting buttons in the SRD dialogue window. The arrow pointing to the right turns real-time correction on or off. The three buttons at its right show you the original without correction, the prescan with artefacts removed, and the artefacts highlighted in red.

The SRD Controls

The SRD dialogue has an Auto button, which allows you to have SilverFast detect scratches and dust automatically, but there is also the opportunity to do it all manually. The latter method might not give the best results unless you are good at masking.

The mask tool in the SRD dialogue serves to protect areas that are not to be touched by the scratch and dust removal algorithm. This ensures that the good parts of the image remain in perfect condition.

Manual corrections start with testing the defect type. You can try different defect types by switching from the current type, another and then see how your setting affects the preview.

The sliders labeled “Defect Size” and “Detection” are preset by the auto mode. For full control over the process, you can change their positions. The Detection slider represents the sensitivity of artefact recognition. Optimum parameters will depend on the type of image, so you will have to experiemtn a bit to get the best result. With sharp images, Detection will be mostly between 1 and 60.

With blurry images or images that have been smoothened Detection will most likely be between 60 and 100. The Defect Size slider sets the size in pixels of the artefact. Values are mostly between 1 and 5.

Always monitor the effect of both sliders in the large preview window, and if necessary check different tiles of the image.

Only when the results of changing the previous two sliders do not yield the desired results, you can change the Intensity slider in small increments to values smaller than 100. This will predominately be the case with detailed images.