Images are acquired using a ZBE Satellite large format stationary camera equipped with a PowerPhase ARI cameraback, 135mm Rodenstock lens and daylight filter. Computer support is currently a Macintosh (PowerMac G4) computer system with 17 gigabytes of storage and ~ 800 megabytes of active memory. Camera images are matched with a 1.8 gamma monitor, relative colorimetrics and the “BEST” quality for rendering profiles. Colorimetrics are calibrated using Kodak Q-60R1 target per ANSI IT8.7/2-1993(1999:04). Intermediate processing of digital herbarium images is achieved with Adobe Photoshop 5.0. Final archives are recorded on CD’s with accessible images available on the Internet via the Lizardtech viewing source Mr. SID.
Every effort has been made to preserve images as accurately as the original. Specimens are photographed at a 1:1 ratio, meaning camera height, DPI (ppi), and output image are all consistent with the original. This means that an 11.5 x 17.5 in. specimen sheet is actually preserved as an 11.5 x 17.5 in. final image. A measurement scale has been included in the images as a reference. In most cases post-production manipulation is unnecessary, but occasionally (usually those with several centimeters of depth of field) it is necessary to use the sharpening and brightness/contrast filters in Adobe Photoshop 5.0.
Digital files are acquired using Phase-One camera software with a gray balanced standard film curve and ISO sensitivity of 400. Specimens are initially recorded as Macintosh (3 vector) images with final format being TIFF files with color depth at 24/16 millions of colors. Generally entire sheet specimens can take anywhere from 5 to 10 minutes (in some cases up to 25 min.) to acquire, have an average of 450 DPI (ppi), and file sizes around 140 megabytes. Close-up’s can take anywhere from 45 seconds to 5 minutes and may exceed 3500 DPI (ppi), and can range from 500 bytes to 80 megabytes in size.