Dynamic Range (DR) is well-defined for scanners. DR=DMAX-DMIN, on a scale of zero to 4. Drum-scanners are the best of the herd, with DR=3.9    DMIN and DMAX are the extremes and tell us how scanners perform in highlights and shadows.

The Nikon IV shown the right panel is a very good film scanner. It has DR=3.6   

Dynamic range is what scanners have, that digital cameras lack. We can easily see why. A digital SLR must capture an image in as little 1/8000th of a second. The signal is processed by a small onboard microprocessor, and written to storage media. Lighting is widely varied. With a scanner, we have calibrated, constant illumination. A scanner may take minutes to record a stationary image, and has the full power of a PC.

The Microtek unit has DR=3.2, still much greater than digital capture, but I am working with medium and large format negatives, which have larger film area than 35mm. Also DMAX=4.2, for very good rendition of highlight areas, a critical concern. The random card is the skill of users with bundled software or Photoshop. Scans require post-processing, and users with higher skill will get better final images.

Computers are the heart of a digital lab. A widescreen laptop is useful on location. Adobe allows users to run a copy of Photoshop CS on laptops, so I can "proof" digital images at high-resolution, or burn CD/DVD media. This machine plugs into my home network, where there are three other machines: Another HP running Windows XP Pro, a Compaq dual-boot PC that usually runs Fedora Core (a flavor of GNU/Linux), and yesterday's generic PC, running Unix.

Various lab functions are spread across the network. One machine has a backup copy of my digital archive, but also boots as GNU/Linux on a separate hard drive. Another machine has a 21" monitor, quite suitable for PhotoShop CS. "The Gimp", free GNU/Linux software, is quickly catching up with Photoshop, and is already better in some ways. Image Magick is another great GNU/Linux application.

PCs share files and printers over the network, on multiple platforms. It helps to know something about network and system administration, as computers used for business must be reliable.

Something Wonderful!

Mr. Gimp is professional-quality image software, and very fast on his feet. A large collection of plugins are also free.

People are sometimes confused by the term "free software". "Free" is explained by the GNU Public License, the only legal document I ever enjoyed reading. We can copy, share, or modify free software, and source code is readily available. In computer science, this is real freedom! Many powerful applications are also offered free of charge, as in "free beer", a great asset to users all over the world. With a worldwide army of talented engineers, GNU/Linux applications are also trouble free. I use the term "free, free, free software", to convey multiple meanings.

Free software and operating systems are now suitable for novice users, software engineers, and everybody in between. To software giants, we are just "consumers". I prefer the perceptions of the free software movement, where we are promoted to the status of human beings. This is not a small philosophical difference!

If you are curious about the free software movement, visit the Free Software Foundation site. A link is provided below. The software industry is always trying to slay the dreamers; they can use our support.

Digital Lab

A digital lab or "darkroom" is whatever computers, software, or peripherals an artist chooses for image manipulation, processing, telecommunications, storage and printing. In computer science lingo, a digital lab is input, processing, and output.

Input

Photo (above): A Nikon Coolscan IV film scanner for 35mm negatives and transparencies. Nikon is the last stop before buying a drum scanner; this company does everything right.

The flatbed scanner is Microtek's i900. The i900 is the latest generation of dual purpose scanners (scans prints and negatives), and performance is quite respectable. I use this scanner for 6x6, 6x7, 4x5, and 5x7 negatives.

Digital capture is also input. This subject is covered on a separate page.

Processing

Above: The one and only Photoshop CS, by Abobe. I've been using this application for a long time, even before it was called "PhotoShop". Anybody remember version 1.0 of "PhotoStyler"?

If you want to hear about the wonders of Photoshop CS, visit the Abobe site. Adobe makes good products, but prices are steep. High levels of skill are required to get the most from Photoshop.

Photoshop has a major weakness. Filtering routines are not very effective. Many users are unaware of Photoshop "plugins" that resolve this issue at additional cost. Some authors create superb plugins, but charge hundreds of dollars for each package. Other authors produce good products at reasonable cost. It pays to shop around.

Plugging the Plugin Site

Advanced Photoshop users can write their own routines, but very few people have this level of skill. If a plugin is well designed, it serves as useful automation. I used various filters from the Plugin Site to process thousands of sports photos last year. Color Washer (color adjustments), Focal Blade (sharpening), and Light Machine (highlights and shadows) are very thoughtful designs (speaking as a software engineer), and a good value.

Harry's plugins are actually small applications, with good functionality and many useful features. Visitors can download "freebies" without cost, so the site is worth a visit. I am not especially fond of software giants, but enjoy the lively cottage industry of developers who write plugin routines.

I also avoid littering my web site with ads, but do support small businesses of all kinds. Bright people like Harry deserve mention.

Output

What is a digital lab? It is simply input (scanners, cameras), processing (hardware/software), and output (CD/DVD, telecommunications, printer).

For output, I often burn CD/DVD media, or transfer files over the internet. I also have an Epson 2200 printer. Epson makes fine digital printers. If you need a printer, check out the site. An Epson 2200 has 2880 x 1440 DPI resolution, and seven "ultrachrome" ink cartridges. Papers and ink are archive quality, rated for 120 years. I will post an update when I confirm this assertion is true.    :-)

Caveat Emptor

These days we often find new PCs "Designed for Microsoft Windows". This often means proprietary firmware and hardware drivers, that place severe limitations on users. If there were truth in advertising, a better label would be "You MUST use Windows and PAY PLENTY for software".

Don't buy a computer designed for Microsoft! Buy a PC designed for you! In my small business, I've saved about $6000.00 by using free software. The free software movement is a wonderful asset to the world, and the best thing to happen so far in the world of software engineering.