Further Information

 
SilverFast Multi-Sampling - Increasing the Dynamic Range
Please click here to reach the Multi-Sampling entry page.
Multi-Sampling Icon
Further benefits of SilverFast Multi-Sampling?
With this function you can effectively bring your scanner to a higher quality level by extending the usable Dynamic Range. You will get enhanced shadow details with reduced or no visible noise, even when you apply Unsharp Masking to make the image appear crisper.

Dynamic Range increase with SilverFast Multi-Sampling
We have measured the Dynamic Range increase according to the new upcoming ISO standard ISO 21550 and as you can see in the diagram below, SilverFast's Multi-Sampling yields dramatic improvement for scanner Dynamic Range. It is interesting to see that even for scanners that already have Multi-Sampling built into their hardware such as the Nikon LS5000, there is a significant increase in Dynamic Range from 2.9 to 3.4. That exemplifies the unique quality of SilverFast's Multi-Sampling process.

Benefits SilverFast Multi-Sampling Benefits SilverFast Multi-Sampling

What is DMAX, Dynamic Range and Density?
Image density is measured from image brightness with optical densiometers, and ranges from 0 to 4, where 0 is pure white and 4 is very black. More density is less brightness. Density is measured on a logarithmic scale. Density of 3.0 is 10 times greater intensity than a density of 2.0. An intensity range of 100:1 is a density of 2.0, and 1000:1 is a density of 3.0. Density 4.0 (which is 10.000:1) is not a theoretical maximum, the math is not limited, but it is a practical maximum of density, because almost nothing you can scan will reach 4.0.

The minimum and maximum values of density capable of being captured by a specific scanner are called DMin and DMax. If the scanner's DMin were 0.2 and DMax were 3.1, its Dynamic Range would be 2.9. DMax implies unique image tone values are distinguishable, and not hidden by electronic noise. Greater Dynamic Range can detect greater image detail in dark shadow areas of the photographic image, because the range is extended at the black end.

DMAX is a value describing how much light variations an input device can differentiate. In general manufacturers publish a value that does not relate to the true usable maximum Dynamic Range, instead it is a theoretical value. When a scanner can still see light variations such as in the shadows of a scan but the CCD already produces visible noise rendering the scan unusable. So briefly speaking DMAX is the maximum density a scanner can detect, while Dynamic Range is the usable range of shades a scanner can differentiate.

Note: Multi-Sampling is available in every SilverFast SE Plus, SilverFast Ai and SilverFast Ai Studio version 6.6.1r1b or later.