Printmaking is among the most resolutely contradictory of the contemporary arts. It 's premised on archaic technology (woodblocks 1,300 years old have been recovered in Korea), but is constantly being rethought, re-tooled and expanded.

The finished product is inherently reproducible, but the technique is used to emphasize the hand wrought and unique. Accomplished artists who have gained fame for work in other media return to the form again and again, yet few who are primarily printmakers can achieve prominence.

But through printmaking, beautiful effects can be achieved that are impossible in other media. A completed image can have the striking power of a rock wall in a river canyon, and with good reason. The process is more akin to sedimentation than anything else, with layer settling upon image layer, each partially obscuring and complementing the last.

It 's also an inherently collaborative process. Competent printmaking is a highly rarefied skill, and few individuals have the necessary resources or skills to cleanly execute ambitious projects. The University of Wisconsin 's Tandem Press is one of a handful of top-tier printmaking facilities nationwide, and their new show, "20 Years with Tandem Press, " presents work by more than a dozen artists who have visited Madison over that time.

The works in this show are tactile, and proudly display the gamut of printmaking techniques to beautiful effect. The best extend a two-dimensional surface into three- and four-dimensional space, and makes the plane that receives the image a substantive, physical presence. You can see layer upon layer of application, and even read backwards in time to the ordered process of constructing the final image.

Highlights include Judy Pfaff 's large scale works -- richly layered collages that present natural forms through a combination of detailed drawings, rough sketches, and architectural renderings.

They often focus on natural forms -- flowers, dogwood, anemones -- and integrate the rich patterning of decorative textiles. The experience of looking at them is like wandering lonely through a distant garden. It 's like looking at a flower, an idea of a flower, a distant memory of a flower, and a shadow of a flower that might have never been, all at once. Her prints are simultaneously intimate and removed, familiar and wholly strange.

Other highlights include Stephen Sorman 's series of diptychs of organic topographies. Sorman overlays images from a small number of plates in different combinations, colors and arrangements. His vision is like ultrasound without boundaries -- revealing, even though you 're not sure what it is you 've seen.

Also wonderful are David Lynch's (yes, that David Lynch) thick and crude collographs pressed into pillow-soft handmade paper, Robert Stackhouse 's dramatic and monochromatic wood-slat structures, splashed roughly across a deep dark space, and Suzanne Caporael 's unnerving and somewhat apocalyptic pseudo-maps.

And so to the final contradiction of printmaking. Despite (or maybe because) it is the most saleable of the arts, printmaking has had to work hardest for a funded right to be included in the academic pantheon.

Tandem Press ' 20th anniversary show is sponsored by the biotech behemoth Promega, and is on display in the public space at the BioPharmaceutical Technology Center in Fitchburg. The Press is currently fundraising for the construction of a permanent studio and gallery space, just east of the Kohl Center.

IF YOU GO

What: 20 Years With Tandem Press

When: 8 a.m.-4 p.m. Mondays to Fridays, through Aug. 29

Where: BioPharmaceutical Technology Center (BTC), 5445 E. Cheryl Parkway, Fitchburg

Admission: Free

Information: www.tandempress.wisc.edu