iSRD® - Infrared Dust and Scratch Removal


Slides and negatives always have small dust particles and tiny scratches on them, even when handled very carefully. Removing them one-by-one takes a tremendous amount of time, since often hundreds or thousands of small defects (dust grains or lint) are found on the original image, which only become visible after digitization. LaserSoft Imaging has developed a reliable solution to this problem.

Contrary to conventional techniques SilverFast‘s dust and scratch removal functionality iSRD® is based on the hardware.* It is using the scanner‘s infrared channel for defect detection. Infrared light has a very wide wave-length, which allows it to pass through film emulsion of negatives and slides without resistance, as opposed to scratches and dust particles that reflect it. iSRD utilizes this behavior as follows. The image is scanned two times - the first is the regular RGB scan and the second is the additional infrared scan that captures defects like dust and scratches only. Then the calculative dust and scratch removal takes effect, only where the infrared channel has detected any defects without losing any important details.

SilverFast iSRD in SilverFast SE & SE Plus
In SilverFast SE and SE Plus, iSRD is especially easy to use and reliable. You may entirely trust in the automatic mode or manually regulate the sensitivity of defect detection using a slider control. In 1:1 preview mode, the results can be pre-evaluated in detail.
  • Automatic scratch removal
  • Manual control of detection sensitivity
  • 1:1 preview mode
  • Mask Tool for limiting correction effects to certain image areas

SilverFast iSRD in SilverFast Ai Studio
The expert mode (only in Ai Studio, HDR Studio and the Archive Suite) offers additional functionality, which helps to mark the defects to be corrected. The Eraser Tool is used to specify image areas, where no correction should be applied at all.
  • Automatic scratch removal
  • Manual control of detection sensitivity
  • Manual control of defect size that should be detected
  • 1:1 preview mode
  • Eraser Tool
  • Mask Tool for limiting correction effects to certain image areas

SilverFast iSRD and SilverFast SRDx
Logo_SRDx_60x48 Logo_iSRD_60x48 SilverFast SRDx is a software-based tool for removing dust and scratches, i.e. in contrast to iSRD it is not using the infrared channel. Thus, it is a great tool for scanners that do not feature any infrared functionality. SilverFast SRDx is also a great addition to SilverFast iSRD. Both features can be optimally combined to remove defects hardware- and software-based. More Info

SilverFast iSRD & Kodachrome
Logo_Kodachrome_60x48 Kodachrome slides are very challenging to scan due to the silver halides this film material is containing. Most scanner software produce blue casts and infrared dust and scratch removal always fails with Kodachromes. The Nikon CoolScan 9000ED, featuring an advanced version of Digital ICE®, was the only device capable of removing dust and scratches from Kodachromes …

… until LaserSoft Imaging had developed a set of Kodachrome features allowing a great variety of scanners to handle Kodachromes. ICC profiles, a special Kodachrome target for IT8 color calibration and, of course, iSRD in combination with SRDx enable SilverFast to scan Kodachromes reliably without color casts and free of dust and scratches.

* Note: The iSRD feature needs information from the infrared channel of the scanner, so please make sure your scanner supports iSRD.

See how effectively SilverFast iSRD® and HDRi work:
Source Infrared Marker Result
Source Infrared Marker Result
Source Infrared Marker Result
Source Infrared Marker Result

SF8_iSRD « iSRD is a highly reliable and comprehensive solution for infrared-based dust and scratch removal. Note the preview functionality, the access to every parameter and the opportunity to work with a mask tool. »
Desktop Dialog 10/11 2011

Logo_Landspeed_Louise « When I finally came to fully understand the iSRD function in SilverFast the “light bulb” fired up. I was thunder struck by the enormous chunk of time-saving help this feature offered. Batman had his utility belt, but I have SilverFast and have to believe I am just getting started with harnessing its power. »
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