Scanning Slides or Negatives
Slides and negatives can be scanned in IT 222. Use the Nikon scanner pictured below.
The scanner is shown configured to scan slides. To scan negatives, call the Help Desk at 7060. For negatives, the middle section of the scanner is replaced by a different "box" that accepts a negative carrier. Most of the scanning on campus has been with slides, so the lab scanner is normally left with this setup. The scanning steps include:
1) Use an airbrush, like the one shown below, to clear dust from the slide.
2) Insert the slide, long side's on the left and right, with the emulsion side down. Usually, this means with the printed label down. The emulsion side is a bit less shiny than the back. Hold the slide up to a light and view it at a sharp angle to detect the emulsion side.
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This scanner works at a maximum of 2900 dpi.
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To scan, enter Photoshop. Pull down under File to Import and choose Nikon Scan 4.
The computer will shift into the Nikon Scan program. This shows basic controls to the left, a preview image, and more controls to the right. There are many detailed settings that can be adjusted when scanning. The images below show normal settings.
When you start a session, the preview image will show the last slide scanned during the last session (even if that slide is no longer in the scanner). If the settings (discussed below) don't need to be changed, scan using the following steps:
1) Hit the Preview button (on the lower left). Wait. On first use, the scanner takes a minute or two to warm up. It always takes a minute or two to perform a preview scan.
2) After the preview appears, you can adjust the crop of your image by dragging the edges of the "crawling ants" rectangle around the image. (You'll also be able to do crops later in Photoshop to your image.)
3) Hit scan -- and wait. When the scan completes, your image will be displayed in Photoshop with the scanner program put away. Now do normal Photoshop editing of your image.
Settings and comments
On the left side controls, you can set whether you are scanning a positive or a negative. This pop-up also has a choice for Kodak. Use this for the special thick, rich, emulsion used on Kodachrome slides. Generally, you should turn off ICE (discussed below) when using Kodachrome. It works for some images, but can incorrectly change colors on your image, particularly in areas of color domination by blues and/or greens.
Other than with Kodachrome (discussed above) leave Digital ICE on. This is a hardware-based system for removing dust and scratch problems (called artifacts). It is remarkably effective. Slides are small. A little dust or scratch becomes very noticeable after the scan. ICE is much more efficient at dealing with this problem that using Photoshop tools.
On the right side you can also turn on or off or adjust two software adjustments that are unique to slide/negative scanning. They are GEM which is a system for reducing the effect of graininess of the original film and ROC which "enhances" the image to reduce the effects of fading due to aging of the film. Together with ICE, these systems should produce a detailed, vibrant image. The down side is that they add some processing time to each scan.
Generally leave the setting on (on the lower right) to Auto focus when a slide is inserted. Slide film normally has some bend or curvature. Because of the need for very high resolution, the scanner should refocus for each slide. This setting will cause that to happen.
Resolution -- We recommend always using 2900 dpi. Unless you crop down to a lower size, this will produce a good file that's around 68 MB. Inside Photoshop, you can do a Save As ... and compress.
Leave Unsharp Mask turned off normally. This sharpening is important, but should be done later in Photoshop (using Filter -> Sharpen -> Unsharp Mask) where you can see a zoomed in portion of the image so that you can control the graininess and loss of softness.
More info to come. This page is a work in progress!
Author: Bob Fry
June 28 2004
