Digitizing the slides: Polaroid SS4000 film scanner (4000 pixels-per-inch), Lasersoft Silverfast software in both AI & HDR versions (http://www.silverfast.com). Scanning at 4000 dots per inch is a fairly slow process (about four minutes per slide) so I normally scan a batch of four slides as 48-bit images (Silverfast AI software) with no adjustments since I can do other things during the 15 minutes required. Typical file size of these 48-bit images is about 110 Mb.

I then use Silverfast HDR to uniquely process each individual 48-bit image. The normal process is to first crop the image, then use the feature generally called Levels to set the black and white points (darkest and lightest points in the picture). This maps the dynamic range (light-to-dark range) of each individual image to the 8-bit (256 level) dynamic range of the computer, and is the most important step in processing.

Following this, I may use what is generally called the Curves control to re-shape the dark-to-light response non-linearly if appropriate. For example, I may wish to “open up” (lighten and increase contrast) in the shadows at the expense of reducing the contrast in other portions of the image.

I then use the individual red, green, and blue curves as necessary to match the colors of the image on my monitor to the slide (or my memory, or just plain to make it look the way I want it to look). My monitor is calibrated with a Gretag-Macbeth Eye-One Photo “puck” and software. I sometimes hold a “sandwich” of a 4x Schneider loupe, the slide, and a small light box to one eye while looking at the monitor with the other eye and adjust the curves for best color match. I find that Provia produces blues that are slightly on the purple side of what I remember from nature, so I may make small adjustments to obtain the blue I remember (or prefer) rather than exactly duplicating the slide.

I then save this corrected version as a 24-bit Photoshop image (typical file size 55 Mb).

Since purchasing my first quality digital body in 2003, no subsequent digitization is involved. I save the images in Canon Raw format and use C1 (Capture One) software from Phase One in Denmark to convert the proprietary Canon Raw format to TIFF files, adjust color balance and exposure, and for noise reduction when using very fast speeds such as ISO 3200. From this point on, processing is in Photoshop as described in that section.