Recently my inkjet proofing printer bit the big one. Yes, inkjet. I have been using it to do soft proofing for clients for a few years now, so they can get a sense of what their plates could potentially produce when printed on an intaglio press. There is some interpolation involved on the part of the printmaker for this to work. Essentially all the variables of this process can be boiled down to three categories: Hardware (printing presses, exposure units, vacuum frames), Software (Photoshop files, calibration curves, printer drivers), and what Perl Programming Guru Tom Christianson once referred to as “Wetware”, or the mind of the worker. Proofing is a kind of software, in a sense: Something that can be modified easily, on the fly to have a desired outcome.
To make soft proofs we output the image on inkjet paper using the same printer driver settings as is used to output the film positive used to create the plate, making sure the correct paper type (in this case Enhanced Matte) is selected in the driver. The output will differ from what is printed on the traditional printing press depending on the style, materials, and preferences of the person running the press and wiping the plates, of course. The printmaker factors this in when reading the inkjet proof.
When our inkjet proofing printer went belly-up, however, we had to make due by producing proofs on the one used to output the film positives. The output between the two would be decidedly different. In fact the output between identical makes and models can be noticeably different.
Since the clients were used to seeing and judging the potential of the plates based on the output from that specific printer, they needed to compare a proof from the old printer with one from the new. Any differences needed to be noted and expectations, adjusted accordingly. Here’s what I advised one client:
“I also included proofs employing the curves you decided on using for the last plates using the new printer. Remember, the files and output will be exactly the same for creating the film and plate. It’s just the proof that may appear different. You’ll need to adjust your interpretation of the proofs depending on how they have changed from the former proofs.
Specifically, you should compare the new proofs to the old proofs I sent to see how this new proofing printer’s output differs from the older ones. If, for example, the new proofs appear slightly darker than the former proofs from last time, you could deduce the bird image’s proofs will be a little *lighter* on the plate than what you’ve gotten accustomed to seeing in the inkjet proofs. You’ll then want to choose a curve from a proof slightly darker than may look good on the proofs you’re used to reading, since these new proofs are theoretically darker than what you’re used to seeing.”
Again, by comparing the new proof to the old they could note any differences and adjust expectations accordingly for all future proofs, providing their workflow remains consistent.
Much like when an exposure unit needs a new bulb (hardware) or the formulation of the film substrate changes (software), recalibration is necessary. Typically this is done in the process compensation curves of the image file (again, software) used to produce the film, or in the exposure times used to make the plates. In this case it’s simply the “wetware” of the printmaker that needed to be adjusted to suit the change in variables.