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Better Scanning Techniques

How to squeeze the utmost quality out of your film/scanner combination.


By Tom Ang

Multipass scanning: For dense negatives or high-contrast, high-density transparencies such as Fuji Velvia, choose multiple scanning if available. If your scanner driver does not offer multiple scanning, all is not lost: See if Silverfast (LaserSoft Imaging) or VueScan (Hamrick Software) drivers support your scanner by checking their websites. The process takes longer, but the results are well worth the wait.

Dealing with moire: If you have problems when scanning printed material, the most effective remedy is usually to scan at a much higher resolution than you need, then downsize later. Another trick is to try placing the original at an angle for scanning and correct the rotation afterwards. Start with an angle of about 15 or 30 degrees. This goes against the advice to avoid rotation (see my later note), but here both the angle and the losses due to interpolation contribute to suppressing moire.

Software or scanner sharpening: One of the choices presented by scanners is either to allow it to perform sharpening, or to do the work yourself in Photoshop. Sharpening (preferably unsharp masking) in the device that is acquiring the image for you may take longer, but it may give you better results than Photoshop. Keep in mind that the scanner’s interpolated preview image is not a reliable indicator of the effects of unsharp masking. The best approach is to determine if you can see any difference. Try scanning an image without sharpening, then with different levels of sharpening performed by the scanner. But remember that scanner-sharpened images will show dust and dirt equally as clear.

Maintaining a dust-free zone
Taking precautions to avoid problems with dust saves a great deal of time and trouble further down the line. So, keep your negative files clean and dust-free before and after filing them with film. Avoid stacking negatives flat or on top of each other; their combined weight will squeeze dust particles on the film into the emulsion or backing to create permanent damage.

When scanning, clean your film and handle it with utmost care. The scanner itself should be kept meticulously clean; keep it covered with a plastic sheet when it’s not being used. The glass platen of a flatbed scanner should be blown free of dust and kept clean of smudges and dampness. Use microfibre cloths designed for cleaning lenses to keep the glass platen spotless.


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